Table Of Contents
Release Notes for the Catalyst 3550 Multilayer Switch, Cisco IOS Release 12.1(22)EA10 and Later
Device Manager System Requirements
Finding the Software Version and Feature Set Running on the Switch
Deciding Which Files to Download from Cisco.com
Upgrading a Switch by Using the Device Manager or Network Assistant
Upgrading a Switch by Using the CLI
Upgrading with a Nondefault System MTU Setting
Recovering from a Software Failure
Cisco IOS Limitations and Restrictions
Device Manager Limitations and Restrictions
Caveats Resolved in Cisco IOS Release 12.1(22)EA10b
Caveats Resolved in Cisco IOS Release 12.1(22)EA10a
Caveats Resolved in Cisco IOS Release 12.1(22)EA10
Documentation Updates in Cisco IOS Release 12.1(22)EA10
Documentation Updates in Cisco IOS Release 12.1(22)EA7
Documentation Updates in Cisco IOS Release 12.1(22)EA6
Regulatory Compliance and Safety Information for the Catalyst 3550 Multilayer Switch
Documentation Updates in Cisco IOS Release 12.1(22)EA5
Documentation Updates in Cisco IOS Release 12.1(22)EA4
Documentation Updates in Cisco IOS Release 12.1(22)EA3
Unsupported CLI Commands in Cisco IOS Release 12.1(22)EA3
Documentation Updates in Cisco IOS Release 12.1(22)EA2
Regulatory Compliance and Safety Information Guide
Documentation Updates in Cisco IOS Release 12.1(22)EA1
Documentation Updates for All Releases
Updates to Software Configuration Guides
Updates to System Message Guides
Obtaining Documentation, Obtaining Support, and Security Guidelines
Release Notes for the Catalyst 3550 Multilayer Switch, Cisco IOS Release 12.1(22)EA10 and Later
Revised June 10, 2008
Cisco IOS Release 12.1(22)EA10, 12.1(22)EA10a, and 12.1(22)EA10b run on all Catalyst 3550 multilayer switches.
Note
Cisco IOS Release 12.1(22)EA10b is the last 12.1 release for the Catalyst 3550 switch. We recommend that you update to a 12.2 SE release of Cisco IOS.
These release notes include important information about this Cisco IOS release and any limitations, restrictions, and caveats that apply to it. Verify that these are the correct release notes for your switch:
•
If you are installing a new switch, see the Cisco IOS release label on the rear panel of your switch.
•
If your switch is on, use the show version privileged EXEC command. See the"Finding the Software Version and Feature Set Running on the Switch" section.
•
If you are upgrading to a new release, see the software upgrade filename for the Cisco IOS version. See the "Deciding Which Files to Download from Cisco.com" section.
For the complete list of Catalyst 3550 switch documentation, see the "Related Documentation" section.
You can download the switch software from this site (registered Cisco.com users with a login password):
http://www.cisco.com/public/sw-center/sw-lan.shtml
This Cisco IOS release is part of a special release of Cisco IOS software that is not released on the same 8-week maintenance cycle that is used for other platforms. As maintenance releases and future Cisco IOS releases become available, they will be posted to Cisco.com in the Cisco IOS software area.
Contents
This information is in the release notes:
•
"System Requirements" section
•
"Upgrading the Switch Software" section
•
"Limitations and Restrictions" section
•
"Documentation Updates" section
•
"Related Documentation" section
•
"Obtaining Documentation, Obtaining Support, and Security Guidelines" section
System Requirements
The system requirements for this release are described in these sections:
•
"Hardware Supported" section on page 2
•
"Device Manager System Requirements" section on page 3
•
"Cluster Compatibility" section on page 4
Hardware Supported
Table 1 lists the hardware supported by this release.
Table 1 Supported Hardware
Switch DescriptionCatalyst 3550-12G
10 GBIC-based Gigabit Ethernet slots and 2 Gigabit Ethernet 10/100/1000BASE-T ports
Catalyst 3550-12T
10 Gigabit Ethernet 10/100/1000BASE-T ports and 2 GBIC1 -based Gigabit Ethernet slots
Catalyst 3550-24
24 autosensing 10/100 Ethernet ports and 2 GBIC-based Gigabit Ethernet slots
Catalyst 3550-24-DC
24 autosensing 10/100 Ethernet ports, 2 GBIC-based Gigabit Ethernet slots, and an on-board DC-power converter
Catalyst 3550-24-FX
24 100BASE-FX ports and 2 GBIC-based Gigabit Ethernet slots
Catalyst 3550-24PWR
24 autosensing 10/100 Ethernet ports, 2 GBIC-based Gigabit Ethernet slots, ability to provide power for Cisco IP Phones and Cisco Aironet Access Points from all 10/100 Ethernet ports, auto-detection and control of inline power on a per-port basis on all 10/100 ports
Catalyst 3550-48
48 autosensing 10/100 Ethernet ports and 2 GBIC-based Gigabit Ethernet slots
GBIC modules
•
1000BASE-SX GBIC
•
1000BASE-LX/LH GBIC
•
1000BASE-ZX GBIC
•
1000BASE-T GBIC
•
GigaStack GBIC
•
CWDM2 fiber-optic GBIC
•
DWDM3 fiber-optic GBIC
Redundant power system
Cisco RPS 300 redundant power system4
Cisco RPS 675 redundant power system5
Cisco RPS 2300 redundant power system
1 GBIC = Gigabit Interface Converter
2 CWDM = coarse wavelength-division multiplexing
3 DWDM = dense wavelength-division multiplexing
4 The Cisco RPS 300 does not support the Catalyst 3550-24-DC or 3550-24PWR switch.
5 The Cisco RPS 675 does not support the Catalyst 3550-24-DC switch.
Device Manager System Requirements
These sections describe the hardware and software requirements for using the device manager:
•
"Hardware Requirements" section on page 3
•
"Software Requirements" section on page 4
Hardware Requirements
Table 2 lists the minimum hardware requirements for running the device manager.
Table 2 Minimum Hardware Requirements
Processor Speed DRAM Number of Colors Resolution Font SizeIntel Pentium II1
64 MB2
256
1024 x 768
Small
1 We recommend Intel Pentium 4.
2 We recommend 256-MB DRAM.
Software Requirements
Table 3 lists the supported operating systems and browsers for using the device manager. The device manager verifies the browser version when starting a session to ensure that the browser is supported.
Note
The device manager does not require a plug-in.
Table 3 Supported Operating Systems and Browsers
Operating System Minimum Service Pack or Patch Microsoft Internet Explorer1 Netscape NavigatorWindows 98
None
5.5 or 6.0
7.1
Windows NT 4.0
Service Pack 6 or later
5.5 or 6.0
7.1
Windows 2000
None
5.5 or 6.0
7.1
Windows XP
None
5.5 or 6.0
7.1
1 Service Pack 1 or higher is required for Internet Explorer 5.5.
Cluster Compatibility
You cannot create and manage switch clusters through the device manager. Instead, use the command-line interface (CLI) or the Network Assistant application.
When creating a switch cluster or adding a switch to a cluster, follow these guidelines:
•
When you create a switch cluster, we recommend that you configure the highest-end switch in your cluster as the command switch.
•
If you are managing the cluster through Network Assistant, the switch with the latest software should be the command switch.
•
The standby command switch must be the same type as the command switch. For example, if the command switch is a Catalyst 3750 switch, all standby command switches must be Catalyst 3750 switches.
For additional information about clustering, see the Getting Started with Cisco Network Assistant and the Release Notes for Cisco Network Assistant (not orderable but available on Cisco.com), the software configuration guide, and the command reference.
CNA Compatibility
Cisco IOS 12.1(22)EA10 and later are only compatible with Cisco Network Assistant (CNA) 5.0 and later. You can download Cisco Network Assistant from this URL:
http://www.cisco.com/pcgi-bin/tablebuild.pl/NetworkAssistant
For more information about Cisco Network Assistant, see the Release Notes for Cisco Network Assistant on Cisco.com.
Upgrading the Switch Software
Before downloading software from Cisco.com to upgrade the switch software, read this section for important information:
•
"Finding the Software Version and Feature Set Running on the Switch" section
•
"Deciding Which Files to Download from Cisco.com" section
•
"Archiving Software Images" section
•
"Upgrading a Switch by Using the Device Manager or Network Assistant" section
•
"Upgrading a Switch by Using the CLI" section
•
"Upgrading with a Nondefault System MTU Setting" section
•
"Recovering from a Software Failure" section
CautionWhen you first upgrade the switch from a Cisco IOS noncryptographic image to a cryptographic image, the bootloader automatically upgrades. The new bootloader upgrade can take up to 30 seconds.
Do not power cycle the switch the first time that you are upgrading the switch to a cryptographic Cisco IOS image. If a power failure occurs when you are copying this image to the switch, call Cisco Systems immediately.
When you upgrade a switch, the switch continues to operate while the new software is copied to flash memory. If flash memory has enough space, the new image is copied to the selected switch but does not replace the running image until you reboot the switch. If a failure occurs during the copy process, you can still reboot your switch by using the old image. If flash memory does not have enough space for two images, the new image is copied over the existing one. Features provided by the new software are not available until you reload the switch.
If a failure occurs while copying a new image to the switch, and the old image has already been deleted, see the "Recovering from Corrupted Software" section in the "Troubleshooting" chapter of the software configuration guide.
Finding the Software Version and Feature Set Running on the Switch
The Cisco IOS image is stored as a bin file in a directory that is named with the Cisco IOS release. A subdirectory contains the files needed for web management. The image is stored on the system board flash device (flash:).
You can use the show version privileged EXEC command to see the software version that is running on your switch. The second line displays C3550-I5Q3L2 for the EMI or C3550-I9Q3L2 for the SMI.
Note
Although the show version output always shows the software image running on the switch (Layer 2 only or Layer 2 and Layer 3), the model name shown at the end of this display is the factory configuration (SMI or EMI) and does not change if you upgrade the software image.
You can also use the dir filesystem: privileged EXEC command to see the directory names of other software images that you might have stored in flash memory.
Deciding Which Files to Download from Cisco.com
The upgrade procedures in these release notes describe how to perform the upgrade by using a combined tar file. This file contains both the Cisco IOS image file and the files needed for the embedded device manager. To upgrade the switch through the CLI, use the tar file and the archive download-sw privileged EXEC command.
Table 4 lists the software filenames for this release. These files are posted on Cisco.com.
Table 4 Cisco IOS Software Files for Catalyst 3550 Switches
Filename
Descriptionc3550-i9q3l2-tar.121-22.EA10a.tar
Cisco IOS SMI1 image file and device manager files.
This image has Layer 2+ and basic Layer 3 routing features.c3550-i5q3l2-tar.121-22.EA10a.tar
Cisco IOS EMI2 image file and device manager files.
This image has Layer 2+ and full Layer 3 features.c3550-i9k2l2q3-tar.121-22.EA10a.tar
Cisco IOS SMI cryptographic image file and device manager files. This image has the Kerberos, Secure Shell (SSH), Layer 2+, and basic Layer 3 routing features.
c3550-i5k2l2q3-tar.121-22.EA10a.tar
Cisco IOS EMI cryptographic image file and device manager files. This image has the Kerberos, SSH, Layer 2, and full Layer 3 features.
1 SMI = standard multilayer image
2 EMI = enhanced multilayer image
The Catalyst 3550 switch is supported by either the SMI, which provides Layer 2+ features and basic Layer 3 routing, or the EMI, which provides Layer 2+ features, full Layer 3 routing, and advanced services. All Catalyst 3550 Gigabit Ethernet switches are shipped with the EMI installed. Catalyst 3550 Fast Ethernet switches are shipped with either the SMI or the EMI installed. After initial deployment, you can order the Enhanced Multilayer Software Image Upgrade kit to upgrade the Catalyst 3550 Fast Ethernet switches from the SMI to the EMI.
Archiving Software Images
Before upgrading your switch software, make sure that you have archived copies of the current Cisco IOS release and the Cisco IOS release to which you are upgrading. You should keep these archived images until you have upgraded all devices in the network to the new Cisco IOS image and until you have verified that the new Cisco IOS image works properly in your network.
Cisco routinely removes old Cisco IOS versions from Cisco.com. See Product Bulletin 2863 for more information:
http://www.cisco.com/en/US/partner/products/sw/iosswrel/ps5187/prod_bulletin0900aecd80281c0e.
HtmlYou can copy the bin software image file on the flash memory to the appropriate TFTP directory on a host by using the copy flash: tftp: privileged EXEC command.
Note
Although you can copy any file on the flash memory to the TFTP server, it is time-consuming to copy all of the HTML files in the tar file. We recommend that you download the tar file from Cisco.com and archive it on an internal host in your network.
You can also configure the switch as a TFTP server to copy files from one switch to another without using an external TFTP server by using the tftp-server global configuration command. For more information about the tftp-server command, see the "Additional File Transfer Commands" section of the Cisco IOS Configuration Fundamentals Command Reference, Release 12.1 at this URL:
Upgrading a Switch by Using the Device Manager or Network Assistant
You can upgrade switch software by using the device manager or Network Assistant. From the feature bar, choose Administration > Software Upgrade. For detailed instructions, click Help.
Note
When using the device manager to upgrade your switch, do not use or close your browser session after the upgrade process begins. Wait until after the upgrade process completes.
Upgrading a Switch by Using the CLI
This procedure is for copying the combined tar file to the Catalyst 3550 switch. You copy the file to the switch from a TFTP server and extract the files. You can download an image file and replace or keep the current image. This procedure requires a configured TFTP server.
CautionWhen you first upgrade the switch from a Cisco IOS noncryptographic image to a cryptographic image, the bootloader automatically upgrades. The new bootloader upgrade can take up to 30 seconds.
Do not power cycle the switch the first time that you are upgrading the switch to a cryptographic Cisco IOS image. If a power failure occurs when you are copying this image to the switch, call Cisco Systems immediately.
To download software, follow these steps:
Step 1
Use Table 4 on page 6 to identify the file that you want to download.
Step 2
Download the software image file.If you have a SmartNet support contract, go to this URL, and log in to download the appropriate files:
http://www.cisco.com/public/sw-center/sw-lan.shtml
To download the SMI and EMI files, select Catalyst 3550 software.
To get authorization and to download the cryptographic software files, select Catalyst 3550 3DES Cryptographic Software.
Step 3
Copy the image to the appropriate TFTP directory on the workstation, and make sure that the TFTP server is properly configured.
For more information, see Appendix B in the Catalyst 3550 Multilayer Switch Software Configuration Guide.
Step 4
Log in to the switch through the console port, a Telnet session, or an SSH session.
Step 5
Verify that you can access the TFTP server from the switch by attempting to ping the TFTP server.
Step 6
Download the image file from the TFTP server to the switch. If you are installing the same version of software that is currently on the switch, overwrite the current image by using this privileged EXEC command:
archive download-sw /overwrite /reload tftp:[[//location]/directory]/image-name.tarThe /overwrite option overwrites the software image in flash memory with the downloaded one.
The /reload option reloads the system after downloading the image unless the configuration has been changed and not been saved.
For //location, specify the IP address of the TFTP server.
For /directory/image-name.tar, specify the directory (optional) and the image to download. Directory and image names are case sensitive.
This example shows how to download an image from a TFTP server at 198.30.20.19 and to overwrite the image on the switch:
Switch# archive download-sw /overwrite tftp://198.30.20.19/c3550-i5q3l2-tar.121-22.EA3.tarYou can also download the image file from the TFTP server to the switch and keep the current image by replacing the /overwrite option with the /leave-old-sw option.
Upgrading with a Nondefault System MTU Setting
If the switch was running Cisco IOS Release 12.1(8)EA1c or earlier and you had used the system mtu global configuration command to configure a nondefault system maximum transmission unit (MTU) size on your switch, follow these steps to upgrade your switch to Cisco IOS Release 12.1(11)EA1 or later:
Step 1
Upgrade the Cisco IOS software to Cisco IOS Release 12.1(11)EA1 or later.
Step 2
If a system MTU size of greater than 2000 is configured on a Gigabit Ethernet switch (Catalyst 3550-12T or Catalyst 3550-12G), use the system mtu global configuration command to set it to the maximum supported MTU size. The maximum allowable system MTU for Gigabit Ethernet switches is 2000 bytes.
Step 3
Save the running configuration by entering the copy running-config startup-config privileged EXEC command.
Step 4
Reload the switch with the new Cisco IOS software.
Step 5
When the switch comes back up with Cisco IOS Release 12.1(11)EA1 or later, reload the switch a second time by using the reload privileged EXEC command so that the system mtu command takes effect.
Recovering from a Software Failure
If the software fails, you can reload the software. For detailed recovery procedures, see the "Troubleshooting" chapter in the software configuration guide.
Installation Notes
You can assign IP information to your switch by using one of these methods:
•
Express Setup program, as described in the switch getting started guide. For information about this guide, see the "Getting Started Guide" section on page 49.
•
CLI-based setup program, as described in the switch hardware installation guide.
•
DHCP-based autoconfiguration, as described in the switch software configuration guide.
•
Manually assigned IP address, as described in the switch software configuration guide.
New Features
These sections describe the new supported hardware and the new software features provided in this release:
•
"New Hardware Features" section
•
"New Software Features" section
New Hardware Features
For a complete list of supported hardware, see the "Hardware Supported" section.
New Software Features
There are no new software features in this release.
Limitations and Restrictions
You should review this section before you begin working with the switches. These are known Cisco IOS limitations that will not be fixed, and there is not always a workaround. Some features might not work as documented, and some features could be affected by recent changes to the switch hardware or software.
These sections describe the limitations and restrictions:
•
"Cisco IOS Limitations and Restrictions" section
•
"Device Manager Limitations and Restrictions" section
Cisco IOS Limitations and Restrictions
These limitations and restrictions apply to Cisco IOS configuration:
•
Modifying a multicast boundary access list does not prevent packets from being forwarded by any multicast routes that were in existence before the access list was modified if the packets arriving on the input interface do not violate the boundary. However, no new multicast routes that violate the updated version of the multicast boundary access list are learned, and any multicast routes that are in violation of the updated access list are not relearned if they age out.
After updating a multicast boundary, the workaround is to use the clear ip mroute privileged EXEC command to delete any existing multicast routes that violate the updated boundary. (CSCdr79083)
•
When an IP packet with a cyclic redundancy check (CRC) error is received, the per-packet per-Differentiated Services Code Point (DSCP) counter (for DSCP 0) is incremented. Normal networks should not have packets with CRC errors.
There is no workaround. (CSCdr85898)
•
If you configure the DHCP server to allocate addresses from a pool to the switch, two devices on the network might have the same IP address. Pooled addresses are temporarily allocated to a device and are returned to the pool when not in use. If you save the configuration file after the switch receives such an address, the pooled address is saved, and the switch does not attempt to access the DHCP server after a reboot to receive a new IP address. As a result, two devices might have the same IP address.
The workaround is to make sure that you configure the DHCP server with reserved leases that are bound to each switch by the switch hardware address. (CSCds55220)
•
The show ip mroute count privileged EXEC command might display incorrect packet counts. In certain transient states (for example, when a multicast stream is forwarded only to the CPU during the route-learning process and the CPU is programming this route into the hardware), a multicast stream packet count might be counted twice.
The workaround is to not trust the counter during this transient state. (CSCds61396)
•
When changing the link speed of a Gigabit Ethernet port from 1000 Mbps to 100 Mbps, there is a slight chance that the port will stop forwarding packets.
The workaround is to shut down the port, and to re-enable it by using the shutdown and no shutdown interface configuration commands. (CSCds84279)
•
In IP multicast routing and fallback bridging, certain hardware features are used to replicate packets for the different VLANs of an outgoing trunk port. If the incoming speed is line rate, the outgoing interface cannot duplicate that speed (because of the replication of the packets). As a result, certain replicated packets are dropped.
There is no workaround. (CSCdt06418)
•
When you use the no interface port-channel global configuration command to remove an EtherChannel group, the ports in the port group change to the administratively down state.
The workaround, when you remove an EtherChannel group, is to enter the no shutdown interface configuration command on the interfaces that belonged to the port group to bring them back on line. (CSCdt10825)
•
In the show interface interface-id privileged EXEC command output, the output buffer failures field shows the number of packets lost before replication. The packets output field shows the successfully sent packets after replication. To determine actual discarded frames, multiply the output buffer failures by the number of VLANs on which the multicast data is replicated.
There is no workaround. (CSCdt26928)
•
Internet Group Management Protocol (IGMP) packets classified by quality of service (QoS) to map the DSCP value and the class of service (CoS) value in a QoS policy map might modify only the DSCP property and leave the CoS value at zero.
There is no workaround. (CSCdt27705)
•
If you assign both tail-drop threshold percentages to 100 percent by using the wrr-queue threshold interface configuration command and display QoS information for this interface by using the show mls qos interface statistics privileged command, the drop-count statistics are always zero even if the thresholds were exceeded.
The workaround is to enter the show controllers ethernet-controllers interface-id privileged EXEC command. In the display, the number of discarded frames includes the frames that were dropped when the tail-drop thresholds were exceeded. (CSCdt29703)
•
Open Shortest Path First (OSPF) path costs and Interior Gateway Routing Protocol (IGRP) metrics are incorrect for switch virtual interface (SVI) ports. Changing the bandwidth of the interface changes the routing metric for the routes when the SVI is used as an outgoing interface.
The workaround is to manually configure the bandwidth of the switch virtual interface (SVI) by using the bandwidth interface configuration command. Changing the bandwidth of the interface changes the routing metric for the routes when the SVI is used as an outgoing interface. (CSCdt29806)
•
Remote Monitoring (RMON) collection functions on physical interfaces, but it is not supported on EtherChannels and switch virtual interfaces (SVIs).
There is no workaround. (CSCdt36101)
•
Multicast router information appears in the show ip igmp snooping mrouter privileged EXEC command output when IGMP snooping is disabled. Multicast VLAN Registration (MVR) and IGMP snooping use the same commands to display multicast router information. In this case, MVR is enabled, and IGMP snooping is disabled.
There is no workaround. (CSCdt48002)
•
When a VLAN interface has been disabled and restarted multiple times by using the shutdown and no shutdown interface configuration commands, the interface might not restart following a no shutdown command.
The workaround is to re-enter the shutdown and no shutdown interface configuration commands to restart the interface. (CSCdt54435)
•
When you use the ip pim spt-threshold infinity interface configuration command, you want all sources for the specified group to use the shared tree and not use the source tree. However, the switch does not automatically start to use the shared tree. No connectivity problem occurs, but the switch continues to use the shortest path tree for multicast group entries already installed in the multicast routing table.
The workaround is to enter the clear ip mroute privileged EXEC command to force the change to the shared tree. (CSCdt60412)
•
Configuring too many multicast groups might result in an extremely low memory condition and cause the software control data structure to go out of sync, causing unpredictable forwarding behavior. The memory resources can only be recovered by entering the clear ip mroute privileged EXEC command.
The workaround is to not configure more than the recommended number of multicast routes on the switch. (CSCdt63480)
•
The dec keyword is not supported in the bridge bridge-group protocol global configuration command. If two Catalyst 3550 switches are connected to each other through an interface that is configured for IP routing and fallback bridging, and the bridge group is configured with the bridge bridge-group protocol dec command, both switches act as if they were the spanning-tree root. Therefore, spanning-tree loops might be undetected.
There is no workaround. (CSCdt63589)
•
If the number of multicast routes configured on the switch is greater than the switch can support, it might run out of available memory, which can cause it to reboot. This is a limitation in the platform-independent code.
The workaround is to not configure the switch to operate with more than the maximum number of supported multicast routes. You can use the show sdm prefer and show sdm prefer routing privileged EXEC commands to view approximate maximum configuration guidelines for the current SDM template and the routing template. (CSCdt63354)
•
When you configure an EtherChannel between a Catalyst 3550 switch and a Catalyst 1900 switch, some of the Catalyst 3550 links in the EtherChannel might go down, but one link in the channel remains up, and connectivity is maintained.
The workaround is to disable the Port Aggregation Protocol (PAgP) on both devices by using the channel-group channel-group-number mode on interface configuration command. PAgP negotiation between these two devices is not reliable. (CSCdt78727)
•
When the switch is operating with equal-cost routes and it is required to learn more unicast routes than it can support, the CPU might run out of memory, and the switch might fail.
The workaround is to remain within the documented recommended and supported limits. (CSCdt79172)
•
The behavior of a software access control list (ACL) with QoS is different from a hardware ACL with QoS. On the Catalyst 3550 switch, when the QoS hardware rewrites the DSCP of a packet, the rewriting of this field happens before software running on the CPU examines the packet, and the CPU sees only the new value and not the original DSCP value.
When the security hardware ACL matches a packet on input, the match uses the original DSCP value. For output security ACLs, the security ACL hardware should match against the final, possibly changed, DSCP value as set by the QoS hardware. Under some circumstances, a match to a security ACL in hardware prevents the QoS hardware from rewriting the DSCP and causes the CPU to use the original DSCP.
If a security ACL is applied in software (because the ACL did not fit into hardware, and packets were sent to the CPU for examination), the match probably uses the new DSCP value as determined by the QoS hardware, whether or not the ACL is applied at the receiving interface or at the sending interface. When packets are logged by the ACL, this problem can also affect whether or not a match is logged by the CPU, even if the ACL fits into hardware and the permit or deny filtering was completed in hardware.
To avoid these issues, whenever the switch rewrites the DSCP of any packet to a value different from the original DSCP, security access control elements (ACEs) should not contain DSCP-match conditions, whether or not the ACL is being applied to an IP access group or to a VLAN map. This restriction does not apply to ACLs used in QoS class maps.
If the switch is not configured to rewrite the DSCP value of any packet, it is safe to match against DSCP in ACLs used for IP access groups or for VLAN maps because the DSCP does not change as the packet is processed by the switch.
The DSCP field of an IP packet encompasses the two fields that were originally designated precedence and type of service (ToS). Statements relating to DSCP apply equally to either IP precedence or IP ToS.
The workaround is to not match on IP precedence, ToS, or DSCP in a receive ACL (RACL), PACL, or VLAN map unless there is no Qos configuration that causes the DSCP to be rewritten. (CSCdt94355)
•
When IGMP filtering is enabled and you use the ip igmp profile global configuration command to create an IGMP filter, reserved multicast addresses cannot be filtered. Because IGMP filtering uses only Layer 3 addresses to filter IGMP reports and due to mapping between Layer 3 multicast addresses and Ethernet multicast addresses, reserved groups (224.0.0.x) are always allowed through the switch. Aliased groups can also leak through the switch. For example, if a user is allowed to receive reports from group 225.1.2.3, but not from group 230.1.2.3, aliasing causes the user to receive reports from 230.1.2.3. Aliasing of reserved addresses means that all groups of the form y.0.0.x are allowed through.
There is no workaround. (CSCdv73626)
•
If a switch stack contains both Catalyst 3550 switches and Catalyst 2900 XL or Catalyst 3500 XL switches, cross-stack UplinkFast (CSUF) is not enabled if the management VLAN on the Catalyst 2900 XL or 3500 XL switches is changed to a VLAN other than VLAN 1 (the default).
The workaround is to make sure that the management VLAN of all Catalyst 2900 XL or 3500 XL switches in the stack is set to VLAN 1. (CSCdv79737)
•
If you use the ip igmp max-groups interface configuration command to set the maximum number of IGMP groups for an interface to 0, the port still receives group reports from reserved multicast groups (224.0.0.x) and their Layer 2 aliases (y.0.0.x).
There is no workaround. (CSCdv79832)
•
If a port is configured as a secure port with the violation mode as restrict, the secure ports might process packets even after maximum limit of MAC addresses is reached, but those packets are not forwarded to other ports.
There is no workaround. (CSCdw02638)
•
Multicast traffic can be temporarily lost when a link comes up in a redundant network and causes the reverse path forwarding (RPF) to change. This only occurs when there are multiple paths between the rendezvous point (RP) and the multicast source.
There is no workaround. (CSCdw27519)
•
The switch might reload when it is executing the no snmp-server host global configuration command. This is a rare condition that can happen if SNMP traps or informs are enabled and the SNMP agent attempts to send a trap to the host just as it is being removed from the configuration and if the IP address of the host (or the gateway to reach the host) has not been resolved by Address Resolution Protocol (ARP).
The workaround is to ensure that the target host or the next-hop gateway to that host is in the ARP cache (for example, by using a ping command) before removing it from the SNMP configuration. Alternatively, disable all SNMP traps and informs before removing any hosts from the SNMP configuration. (CSCdw44266)
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When you access the CISCO-STACK-MIB portTable, the mapping might be off by one from the mapping given by the switch. The objects in this table are indexed by two numbers: portModuleIndex and portIndex. The allowable values for portModuleIndex are 1 through 16. Because 0 is not an allowable value, the value 1 represents module 0.
The workaround is to use the value 1 to represent module 0. (CSCdw71848)
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If a port on the Catalyst 3550 switch that is running the Multiple Spanning Tree Protocol (MSTP) is connected to another switch that belongs to a different multiple spanning-tree (MST) region, the Catalyst 3550 port is not recognized as a boundary port when you start the protocol migration process by using the clear spanning-tree detected-protocols interface interface-id privileged EXEC command. This problem occurs only on the root bridge, and when the root bridge is cleared, the boundary ports are not shown because the designated ports do not receive any bridge protocol data units (BPDUs) unless a topology change occurs. This is the intended behavior.
The workaround is to configure the Catalyst 3550 switch for per-VLAN spanning-tree plus (PVST+) by using the spanning-tree mode pvst global configuration command bridge, and then change it to MSTP by using the spanning-tree mode mst global configuration command. (CSCdx10808)
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When a large number of VLANs and a large number of trunk ports with allowed VLAN lists are configured on the switch, if you enter the no switchport trunk allowed vlan interface-range command to remove the allowed list for all the trunk ports, the SYS-3-CPUHOG system message might appear.
The workaround is to use the no switchport trunk allowed vlan interface configuration command on each trunk port to remove the allowed list for all the trunk ports. (CSCdx17189)
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When 1000 VLANs and more than 40 trunk ports are configured, and the spanning-tree mode changes from MSTP to PVST+ or the reverse, this message appears on the console:
%ETHCNTR-3-RA_ALLOC_ERROR: RAM Access write pool I/O memory allocation failureThere is no workaround. However, we recommend that you reload the switch by using the reload privileged EXEC command. To avoid this problem, configure the system with fewer VLANs and fewer trunk ports, or use the switchport trunk allowed vlan interface configuration command to reduce the number of active VLANs on each trunk port. (CSCdx20106)
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Ternary content addressable memory (TCAM) generation might fail when there are multiple ACLs in a policy-map. If you add an entry that checks TCP flags to an access list that is used for QoS classification, the system might report that a hardware limitation has been reached for the policy map. This can occur when the policy map already contains several other access list entries that check different TCP flags or that check TCP or User Datagram Protocol (UDP) port numbers by using an operation different from equal (eq), such as not equal (ne), less than (lt), greater than (gt), or range. When the hardware limitation is reached, the service-policy input policy-map-name interface configuration command is removed from the running configuration of the interface.
Checking for TCP flags and TCP/UDP port numbers using operators other than eq share some of the same hardware resources. The switch supports no more than six checks within a single policy map. An identical check repeated in multiple entries in the same policy map counts as a single instance. If this limit is reached during a TCP or an UDP port number check, the software can often work around the problem by allocating extra entries in the TCAM. There is no workaround if the limit is reached during a check against the TCP flags in the packet. Similar checks in a port ACL applied to the same physical interface as the policy map also count toward the limit.
Because these resources are allocated on a first-come, first-serve basis, rearranging the order of ACLs within a policy map or the order of entries within a single ACL, placing the TCP flags checks as early as possible, might enable the policy map to be loaded into the hardware.
Similar limits apply for any combination of input VLAN maps, input router ACLs, output VLAN maps, and output router ACLs that share the same VLAN label. The switch supports eight checks for all features on the same VLAN label. When the limit is reached, the system might forward packets by using the CPU rather than through hardware, greatly reducing system performance. To determine the VLAN label assigned to a VLAN or interface on input or output, use the show fm vlan or show fm interface privileged EXEC commands. Then use the show fm vlan-label privileged EXEC command to determine which set of features (input VLAN map, input router ACL, output VLAN map, or output router ACL) share this label.
These are the workarounds:
–
Re-arrange the order of classes within the policy map and the order of entries within the individual access lists in the policy map or within any IP port ACL applied to the interface so that checks for TCP flags are made as early as possible within the policy map. You can also re-arrange the order of the individual ACLs within a VLAN map and the order of the individual entries in a security ACL.
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Add an extra entry to the front of an ACL that checks for the same TCP flags that are checked later on in the ACL. If the first entry of the ACL already matches only the TCP protocol, you can duplicate the entry and add a check for the appropriate TCP flags.
–
Reduce the number of different combinations of TCP flags being tested.
If the other workarounds fail, avoid combining any check against the TCP flags with gt, lt, ne, or range checks within the policy map and port ACL configured on the interface or within the VLAN maps and router ACLs that share the same VLAN label. (CSCdx24363)
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If you apply an ACL to an interface that has a QoS policy map attached and the ACL is configured so that the packet should be forwarded by the CPU or if the configured ACL cannot fit into the TCAM, all packets received from this interface are forwarded to the CPU. Because traffic forwarded to the CPU cannot be policed by the policer configured on the interface, this traffic is not accurately rate-limited to the configured police rate.
The workaround, when QoS rate limiting is configured on an interface, is to configure applied ACLs so that packets are not forwarded by the CPU or to reduce the number of ACEs in the ACL so that it can fit into the TCAM. (CSCdx30485)
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When you reboot a Catalyst 3550-24-FX switch, it might loop back packets received on a 100BASE-FX port to its link partner. This can occur before the software takes control of the system and lasts for about 200 milliseconds.
As a result, the link partner might shut down the port when it detects loopback packets, or MAC addresses might be learned on the wrong ports on upstream switches. The network might be unable to deliver packets to a few devices for up to 5 minutes after rebooting the Catalyst 3550-24-FX switch when:
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The Catalyst 3550-24-FX switch is connected to one or more switches in the network.
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Spanning tree is disabled in the network or the Port Fast feature is enabled on the ports connected to the Catalyst 3550-24-FX switch.
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The Catalyst 3550-24-FX switch is powered cycled or reloaded from the CLI.
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One or more devices in the network transmit a broadcast or multicast packet during the 200-millisecond timing window while the Catalyst 3550-24-FX switch is booting up.
This problem corrects itself after 5 minutes or when these devices transmit a broadcast or multicast packet, whichever comes first.
The workaround is to enable spanning tree in the network and to make sure that the Port Fast feature is disabled on all ports connected to the Catalyst 3550-24-FX switch. (CSCdx45558)
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If the switch fails for any reason while you are exiting VLAN configuration mode (accessed by entering the vlan database privileged EXEC command), there is a slight chance that the VLAN database might get corrupted. After resetting from the switch, you might see these messages on the console:
%SW_VLAN-4-VTP_INVALID_DATABASE_DATA: VLAN manager received bad data of type device type: value 0 from vtp database$SW_VLAN-3-VTP_PROTOCOL_ERROR: VTP protocol code internal errorThe workaround is to use the delete flash:vlan.dat privileged EXEC command to delete the corrupted VLAN database. Then reload the switch by using the reload privileged EXEC command. (CSCdx19540)
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If you apply a large access control list (ACL) and it fills the entire TCAM, the MVR IP multicast data packets are sent to the switch CPU and are not forwarded to the MVR receiver ports.
There is no workaround. (CSCdx80751)
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If you create a policy map by using the policy-map policy-map-name global configuration command, enter the class class-map-name policy-map configuration command, and then immediately exit from the policy-map class configuration mode, the policy map does not show its class-map association.
The workaround is to enter another command (such as the police, trust, or set policy-map class configuration commands) after entering the class class-map-name policy-map configuration command. (CSCdx81650)
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If a switch and a Cisco redundant power system (RPS) 300 or 675 are connected to different power sources and the switch power supply fails, the Cisco RPS supplies power to the switch. However, after the switch power supply is restored, the Cisco RPS continues providing power to the switch.
When the switch stops receiving power from the Cisco RPS and uses its own power supply to power the switch, pressing the Standby/Active button on the Cisco RPS might cause the switch to reload.
Note
We recommend that you connect the switch and the Cisco RPS to the same power source. For more information, see the Cisco RPS installation guide.
There is no workaround. (CSCdx81023)
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When you insert a GigaStack GBIC in a GBIC module slot, the CPU utilization might increase by as much as 6 percent. This increase occurs for each GigaStack GBIC added to the switch. Other types of GBICs do not cause additional CPU utilization.
There is no workaround. (CSCdx90515)
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When a community string is assigned by the cluster command switch, you cannot get any dot1dBridge MIB objects by using a community string with a VLAN entity from a cluster member switch.
The workaround is to manually add the cluster community string with the VLAN entity on the member switches for all active VLANs shown in the show spanning-tree summary display. This is an example of such a change, where cluster member 3 has spanning tree on vlan 1-3, and the cluster commander community string is public@es3.
Switch(config)# snmp community public@es3@1 ROSwitch(config)# snmp community public@es3@2 ROSwitch(config)# snmp community public@es3@3 ROThere is no workaround. (CSCdx95501)
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A Remote Switched Port Analyzer (RSPAN) source session does not forward monitored traffic to the RSPAN destination session if there is an egress SPAN source port in the session with port security or IEEE 802.1x authentication enabled.
There is no workaround. (CSCdy21035)
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Not all traffic is properly mirrored by RSPAN when a port is monitored for egress traffic and the RSPAN VLAN is carried through a Layer 2 protocol tunnel to the RSPAN destination switch.
This happens because the MAC addresses for the original packets as well as the mirrored RSPAN packets are all learned on the tunnel VLAN, so the RSPAN traffic is no longer properly segregated on the tunneling switches.
The workaround is to not include any RSPAN VLANs in any Layer 2 protocol tunnels unless the tunnel is dedicated to a single RSPAN VLAN. (CSCdy37188)
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Ingress forwarding on a SPAN destination port does not work if there is an egress SPAN source port in the session with port security or IEEE 802.1x authentication enabled.
There is no workaround. (CSCdy44646)
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When the switch receives multicast traffic and IGMP join for requests a multicast group at the same time and it begins to forward the multicast packets, some of the packets might be dropped.
There is no workaround. (CSCdy80326)
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If a Catalyst 3550 switch is connected to two routers (Router 1 and Router 2) in this topology:
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The link between Router 1 and the switch is a bridge virtual interface (BVI) that belongs to two VLANs (VLAN 100 and VLAN 110) and uses one IP address. The IP subnet for the BVI is the same for both VLANs. The ports in both VLANs operate as Layer 2 interfaces. An SVI with an IP address is configured only on VLAN 100.
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The link between Router 2 and the switch is an IP interface that only belongs to VLAN 110.
IP connectivity then exists between Router 1 and the switch. There is no IP connectivity between Router 2 and the switch.
The workaround is to configure another SVI with an IP address on the Catalyst 3550 switch that would be reachable from Router 2. (CSCdy82042)
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The 5 minute input rate and 5 minute output rate fields in the output of the show interfaces privileged EXEC command show both rates as 0 bits/sec. If you enter the show interfaces command more than once, these fields might show values greater than 0 bits/sec.
There is no workaround. (CSCdz06305)
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When the link between a device with an AC power supply and a Catalyst 3550-24PWR switch is 10 Mbps and half duplex, and the AC power supply is turned off, the switch is in the error-disabled state.
The workaround is remove the AC power supply, disconnect the Ethernet cable, and then reconnect the Ethernet cable. This ensures that the switch uses inline power. (CSCdz16265)
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When you perform a ping from a VLAN to another VLAN on the same switch, the VLAN counter does not change.
There is no workaround. (CSCdz17863)
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When you configure a dynamic switchport by using the switchport access vlan dynamic interface configuration command, the port might allow unauthorized users to access network resources if the interface changes from access mode to trunk mode through Dynamic Trunking Protocol (DTP) negotiation.
The workaround is to configure the port as a static access port. (CSCdz32330)
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A Catalyst 3550 switch does not adjust the power allocation based on the IEEE class of the powered device. When an IEEE-compliant powered device is connected to a switch, it allocates 15 W (the default) to the port.
There is no workaround. (CSCdz37516)
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When an IEEE 802.1x-authenticated client is disconnected from an IP phone, hub, or switch and does not send an EAPOL-Logoff message, the switch interface does not transition to the unauthorized state. If this happens, it can take up to 60 minutes for the interface to transition to the unauthorized state when the re-authentication time is the default value (3600 seconds).
The workaround is to change the number of seconds between re-authentication attempts by using the dot1x timeout re-authperiod seconds global configuration command. (CSCdz38483)
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If a spanning-tree loop occurs, this message might appear:
MALLOCFAIL, alignment 0. -Process=Syslog Traps -Traceback= 1A3740This message appears because the switch has run out of I/O memory and is unable to allocate a packet buffer to report the error. You can also verify if the switch runs out of I/O memory by using the show memory privileged EXEC command.
The workaround is to reconfigure the spanning tree to remove the loop. (CSCdz51522)
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When a switch receives a bridge STP BPDU from an access port and the egress port is a trunk port, the switch assigns the BPDU a CoS value of 0 instead of 7.
There is no workaround. (CSCdz54043)
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After a MAC address is relearned on a new interface, traffic might not be immediately forwarded to the MAC addresses.
There is no workaround. (CSCdz75459)
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If a switch configuration contains a large ACL and a per-port per-VLAN policy map and both are attached to two interfaces, when you are copying it to the running configuration, this process might fail because the switch runs out of memory.
These are the workarounds:
–
Copy the new configuration file to the config.txt file, and reboot the switch.
–
Save the configuration file as two files: one containing only the ACL configuration and one containing the rest of the configuration (including the QoS and interface configuration). Add the first configuration file to the running-configuration file, and then add the second file to the running-configuration file. (CSCdz54115)
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After the no interface tunnel0 global configuration command is entered to remove the tunnel interface, the output from the show running-config privileged EXEC command still shows the tunnel interface that was removed.
This can occur if HSRP interface tracking is configured on another interface to track a tunnel interface, if the no interface command was entered before the HSRP tracking configuration was removed, or if the no standby tunnel0 global configuration command was entered on the other interface to disable tracking.
These are the workarounds:
–
Before removing the tunnel interface from the configuration, remove the HSRP interface tracking commands in the configuration that specify the tunnel interface.
–
Use the no standby track global configuration command without specifying an interface to disable HSRP tracking. (CSCdz66450)
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Beginning in Cisco IOS Release 12.1(13)EA1, these are the default settings for an IP phone connected to a switch:
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The port trust state is to not trust the priority of frames arriving on the IP phone port from connected devices.
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The CoS value of incoming traffic is overwritten and set to zero. (CSCdz76948)
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The Catalyst 3550 switch only supports the read operation in the sysClearPortTime MIB object (.1.3.6.1.4.1.9.5.1.1.13) in the CISCO-STACK-MIB. Use the clear counters privileged EXEC command to clear the counters.
There is no workaround. (CSCdz87897)
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When a Catalyst 3550 switch is connected to a three-port Gigabit Ethernet module in a Cisco 12000 Gigabit Switch Router (GSR) that is configured for Ethernet over Multiprotocol Label Switching (EoMPLS), the switch does not reliably send frames to the GSR.
The workaround is to configure the Catalyst 3550 Gigabit Ethernet interface with the spanning-tree portfast interface configuration command. (CSCea04746)
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On a switch running Cisco IOS Release 12.1(12c)EA1 or later, if the switch MTU value is set to a value greater than 1500 and the authentication server and the intermediate devices are not configured with a compatible MTU value, IEEE 802.1x authentication with EAP-Transparent LAN Services (TLS) might fail.
The workaround is to reset the switch MTU value to the default value or to configure the same MTU value on the switch, the authentication server, and the intermediate devices. (CSCea05682)
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If a cable on an ingress interface is disconnected, an Alteon A184 cannot detect when a 1000BASE-X link between two Catalyst 3550 switches is down.
There is no workaround. (CSCea09786)
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Performing an extended ping from one interface to another interface on the same switch can cause high CPU utilization. This can occur when a large number of ping packets are sent and received and is the expected behavior.
The workaround is to not perform a ping from one interface to another on the same switch. (CSCea19301)
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The switch does not create an adjacency table entry when the ARP timeout value is 15 seconds and the ARP request times out.
The workaround is to not set an ARP timeout value lower than 120 seconds. (CSCea21674)
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If the output from the show tcam inacl 1 statistics privileged EXEC command shows that the Ternary content addressable memory (TCAM) is not full and you are applying an ACL, this system message might appear:
%FM-3-UNLOADING: Unloading input vlan label 1 feature from all TCAMsThere is no workaround. (CSCea25658)
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If you are configuring a policy map on an interface by using named ACLs and the policy map has 13 named ACLs that include explicit deny statements, these messages might appear when you add an ACL:
QoS: Programming TCAM failed: Unsuccessful ACL mergeService Policy attachment failedService Policy xxxx not attachedQM-4-HARDWARE_NOT_SUPPORTED: Hardware limitation has reached for policymap xxxxThese are the workarounds. Only one of these is necessary:
–
Use numbered ACLs.
–
Do not use explicit deny statements because the end of an ACL has an implicit deny statement. (CSCec46594)
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When three or more Catalyst 3550-24PWR switches are connected through GigaStack GBICs, you can access all the VLANs on the uplink switch, but you can only access VLAN 1 on the other switches.
The workaround is to enter the switchport mode trunk interface configuration command on all of the GigaStack interfaces and to do one of these:
–
Use the shutdown and then the no shutdown interface configuration commands on the ports.
–
Save the switch configuration by using the copy running-config startup-config privileged EXEC command, and reload all the switches. (CSCec86258)
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The switch uses the same MAC address for all VLAN interfaces. If the destination MAC address in a packet is the same as the MAC address of the VLAN interface, and the VLAN interface for that VLAN is shut down or does not exist, the switch drops the packet.
There is no workaround. (CSCed12004)
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When the switch has many routes that use loadsharing among multiple next hops, some of the routes might not loadshare but instead pick only one of the next hops for forwarding all packets on that route. This happens when the portion of the adjacency RAM that has been allotted for multipath routes has been used up.
There is no workaround. (CSCed22152)
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The DHCP option-82 format on the Catalyst 3550 switch is inconsistent with other Cisco switches. When the Catalyst 3550 switch is used as the relay agent with DHCP snooping and the option-82 feature using the VLAN-module-port (vlan-mod-port) format, the switch does not assign the correct value to the port identifier (circuit ID suboption). The value is offset by 1 from the actual interface module- and port-number values. The circuitID/port-identifier for Fast Ethernet and Gigabit Ethernet interfaces also have the same module-number but different port-number values. For example, on a Catalyst 3550-24 switch, fastethernet0/1 is reported as module 0/port 0, and gigabitethernet0/1 is reported as module 0/port 24.
There is no workaround. (CSCed29525)
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When connected to some third-party devices that send early preambles, a switch port operating at 100 Mbps full duplex or 100 Mbps half duplex might bounce the line protocol up and down. The problem is seen only when the switch is receiving frames.
The workaround is to configure the port for 10 Mbps and half duplex or to connect a hub or a nonaffected device to the switch. (CSCed39091)
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Packets received from media types that require SNAP encapsulation of IPv4 packets require the switch to forward SNAP-encapsulated packets. Layer 2 forwarding of IPv4 in SNAP encapsulation ordinarily takes place in hardware (unless a VLAN map or port ACL contains an IP ACL). However, on the Catalyst 3550 switch, Layer 3 forwarding of IPv4 in SNAP can only be done in software. SNAP-encapsulated IPv4 packets that are directed to the router MAC address or the HSRP group MAC address (if this device is the active router in the HSRP group) are forwarded to the switch CPU, potentially causing high CPU utilization levels.
This is a hardware limitation, and there is no workaround. (CSCed59864)
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The undersize error counter is incrementing when no undersize packets are present. This condition occurs on IEEE 802.1Q tunnel ports connected to a Nortel or an Alteon Load Balancer.
There is no workaround. (CSCed73388)
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When multi-VRF-CE is enabled on the switch, the switch does not support the ip directed-broadcast interface configuration command used to enable forwarding of IP-directed broadcasts on an interface.
There is no workaround. (CSCee05670)
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When IGMP snooping is disabled and you enter the switchport block multicast interface configuration command, IP multicast traffic is not blocked. The switchport block multicast interface configuration command is only applicable to non-IP multicast traffic.
There is no workaround. (CSCee16865)
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When one Fast Ethernet port on a switch (Switch A) is connected to a packet generator, and another Fast Ethernet port on the switch is connected to a Gigabit Ethernet interface on another switch (Switch B), multicast traffic sent from Switch A to Switch B is incorrectly counted. The output from the show mls qos interface interface-id statistics command for the Gigabit Ethernet interface is incorrect.
There is no workaround. (CSCee19574)
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You cannot modify the reAuthMax parameter (defined in the IEEE 802.1x specification), which is set to 2. There is no switch command to address this function. Do not use the dot1x max-req interface configuration command for this function.
There is no workaround. (CSCee80587)
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When port security is enabled on an interface in restricted mode and the switchport block unicast interface command has been entered on that interface, MAC addresses are incorrectly forwarded when they should be blocked.
The workaround is to enter the no switchport block unicast interface configuration command on that specific interface. (CSCee93822)
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If packets with a bad cyclic redundancy check (CRC) are received on a port, the switch might learn the source MAC address of the bad packet.
There is no workaround. (CSCef15178)
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If four switches are connected in a cascaded stack through the GigaStack GBICs, the link between the second and third switches goes down, and is then reconnected, the GBIC LEDs blink amber. The GBIC ports take approximately 1 minute to come up.
There is no workaround. (CSCef17198)
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Cross-stack UplinkFast (CSUF) convergence might be slow when the root port goes down in a switch stack that is connected through Gigastack GBICs.
There is no workaround. (CSCef18020)
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Whenever a single frame is subject to both ingress and egress SPAN, and both the ingress and the egress SPAN are sent to the same SPAN destination port, the egress copy of the frame is sent out the SPAN destination port before the ingress copy of the frame.
There is no workaround. (CSCef97043)
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SNMP get for CiscoEnvMonSupplyStatusDescr, which gives power supply status, does not supply accurate information.
There is no workaround. (CSCeg08870)
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The Cisco redundant power system (RPS) 300 supports the Catalyst 3550 multilayer switch and provides redundancy for up to six connected devices until one of these devices requires backup power. If a connected device has a power failure, the Cisco RPS 300 immediately begins supplying power to that device and sends status information to other connected devices that it is no longer available as a backup power source. As described in the device documentation, when the RPS LED on the switch is amber, the Cisco RPS is connected but down. However, this might merely mean that the Cisco RPS is in standby mode. Press the Standby/Active button on the Cisco RPS to put it into active mode. You can view Cisco RPS status through the CLI by using the show rps privileged EXEC command. For more information, see the Cisco RPS documentation.
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Storm control or traffic suppression (configured by using the storm-control {broadcast |


