Catalyst 6500 Release 12.2SXF and Rebuilds Software Configuration Guide - Configuring Local SPAN, Remote SPAN (RSPAN), and Encapsulated RSPAN [Cisco Catalyst 6500 Series Switches]

Table Of Contents

Configuring Local SPAN, RSPAN, and ERSPAN

Understanding How Local SPAN, RSPAN, and ERSPAN Work

Local SPAN, RSPAN, and ERSPAN Overview

Local SPAN Overview

RSPAN Overview

ERSPAN Overview

Monitored Traffic

Local SPAN, RSPAN, and ERSPAN Sources

Source Ports

Source VLANs

Local SPAN, RSPAN, and ERSPAN Destination Ports

Local SPAN, RSPAN, and ERSPAN Configuration Guidelines and Restrictions

Feature Incompatiblities

Local SPAN, RSPAN, and ERSPAN Session Limits

PFC3

PFC2

Local SPAN, RSPAN, and ERSPAN Guidelines and Restrictions

VSPAN Guidelines and Restrictions

RSPAN Guidelines and Restrictions

ERSPAN Guidelines and Restrictions

Configuring Local SPAN, RSPAN, and ERSPAN

Configuring Destination Port Permit Lists (Optional)

Configuring Local SPAN

Configuring RSPAN

Configuring RSPAN VLANs

Configuring RSPAN Source Sessions

Configuring RSPAN Destination Sessions

Configuring ERSPAN

Configuring ERSPAN Source Sessions

Configuring ERSPAN Destination Sessions

Configuring Source VLAN Filtering for Local SPAN and RSPAN

Configuring a Destination Port as an Unconditional Trunk

Configuring Destination Trunk Port VLAN Filtering

Verifying the Configuration

Configuration Examples

Configuring Local SPAN, RSPAN, and ERSPAN

This chapter describes how to configure local Switched Port Analyzer (SPAN), remote SPAN (RSPAN), and Encapsulated RSPAN (ERSPAN) on the Catalyst 6500 series switches. With a PFC3, Release 12.2(18)SXE and later releases support ERSPAN (see the "ERSPAN Guidelines and Restrictions" section).

Note•For complete syntax and usage information for the commands used in this chapter, refer to the Cisco IOS Master Command List, Release 12.2SX at this URL:

http://www.cisco.com/en/US/docs/ios/mcl/122sxmcl/12_2sx_mcl_book.html

•OSM WAN ports and FlexWAN ports do not support SPAN, RSPAN or ERSPAN.

•PFC2 does not support ERSPAN.

This chapter consists of these sections:

•Understanding How Local SPAN, RSPAN, and ERSPAN Work

•Local SPAN, RSPAN, and ERSPAN Configuration Guidelines and Restrictions

•Configuring Local SPAN, RSPAN, and ERSPAN

Understanding How Local SPAN, RSPAN, and ERSPAN Work

These sections describe how local SPAN, RSPAN, and ERSPAN work:

•Local SPAN, RSPAN, and ERSPAN Overview

•Local SPAN, RSPAN, and ERSPAN Sources

•Local SPAN, RSPAN, and ERSPAN Destination Ports

Local SPAN, RSPAN, and ERSPAN Overview

Local SPAN, RSPAN, and ERSPAN sessions allow you to monitor traffic on one or more ports, or one or more VLANs, and send the monitored traffic to one or more destination ports. With Release 12.2(18)SXD and later releases, you can configure per-VLAN filtering on destination trunk ports.

Local SPAN, RSPAN, and ERSPAN all send traffic to a network analyzer such as a SwitchProbe device or other Remote Monitoring (RMON) probe. SPAN does not affect the switching of traffic on source ports or VLANs. SPAN sends a copy of the packets received or transmitted by the source ports and VLANs to the destination port. You must dedicate the destination port for SPAN use.

These sections provide an overview of local SPAN, RSPAN, and ERSPAN:

•Local SPAN Overview

•RSPAN Overview

•ERSPAN Overview

•Monitored Traffic

Local SPAN Overview

A local SPAN session is an association of source ports and source VLANs with one or more destination ports. You configure a local SPAN session on a single switch. Local SPAN does not have separate source and destination sessions.

Local SPAN sessions do not copy locally sourced RSPAN VLAN traffic from source trunk ports that carry RSPAN VLANs. Local SPAN sessions do not copy locally sourced RSPAN GRE-encapsulated traffic from source ports.

Each local SPAN session can have either ports or VLANs as sources, but not both.

Local SPAN copies traffic from one or more source ports in any VLAN or from one or more VLANs to a destination port for analysis (see Figure 52-1). For example, as shown in Figure 52-1, all traffic on Ethernet port 5 (the source port) is copied to Ethernet port 10. A network analyzer on Ethernet port 10 receives all traffic from Ethernet port 5 without being physically attached to Ethernet port 5.

Figure 52-1 Example SPAN Configuration

RSPAN Overview

RSPAN supports source ports, source VLANs, and destination ports on different switches, which provides remote monitoring of multiple switches across your network (see Figure 52-2).

RSPAN consists of an RSPAN source session, an RSPAN VLAN, and an RSPAN destination session. You separately configure RSPAN source sessions and destination sessions on different switches. To configure an RSPAN source session on one switch, you associate a set of source ports or VLANs with an RSPAN VLAN. To configure an RSPAN destination session on another switch, you associate the destination ports with the RSPAN VLAN.

The traffic for each RSPAN session is carried as Layer 2 nonroutable traffic over a user-specified RSPAN VLAN that is dedicated for that RSPAN session in all participating switches. All participating switches must be trunk-connected at Layer 2.

RSPAN source sessions do not copy locally sourced RSPAN VLAN traffic from source trunk ports that carry RSPAN VLANs. RSPAN source sessions do not copy locally sourced RSPAN GRE-encapsulated traffic from source ports.

Each RSPAN source session can have either ports or VLANs as sources, but not both.

The RSPAN source session copies traffic from the source ports or source VLANs and switches the traffic over the RSPAN VLAN to the RSPAN destination session. The RSPAN destination session switches the traffic to the destination ports.

Figure 52-2 RSPAN Configuration

ERSPAN Overview

ERSPAN supports source ports, source VLANs, and destination ports on different switches, which provides remote monitoring of multiple switches across your network (see Figure 52-3).

ERSPAN consists of an ERSPAN source session, routable ERSPAN GRE-encapsulated traffic, and an ERSPAN destination session. You separately configure ERSPAN source sessions and destination sessions on different switches.

To configure an ERSPAN source session on one switch, you associate a set of source ports or VLANs with a destination IP address, ERSPAN ID number, and optionally with a VRF name. To configure an ERSPAN destination session on another switch, you associate the destination ports with the source IP address, ERSPAN ID number, and optionally with a VRF name.

ERSPAN source sessions do not copy locally sourced RSPAN VLAN traffic from source trunk ports that carry RSPAN VLANs. ERSPAN source sessions do not copy locally sourced ERSPAN GRE-encapsulated traffic from source ports.

Each ERSPAN source session can have either ports or VLANs as sources, but not both.

The ERSPAN source session copies traffic from the source ports or source VLANs and forwards the traffic using routable GRE-encapsulated packets to the ERSPAN destination session. The ERSPAN destination session switches the traffic to the destination ports.

Figure 52-3 ERSPAN Configuration

Monitored Traffic

These sections describe the traffic that local SPAN, RSPAN, and ERSPAN can monitor:

•Monitored Traffic Direction

•Monitored Traffic

•Duplicate Traffic

Monitored Traffic Direction

You can configure local SPAN sessions, RSPAN source sessions, and ERSPAN source sessions to monitor ingress traffic (called ingress SPAN), or to monitor egress traffic (called egress SPAN), or to monitor traffic flowing in both directions.

Ingress SPAN copies traffic received by the source ports and VLANs for analysis at the destination port. Egress SPAN copies traffic transmitted from the source ports and VLANs. When you enter the both keyword, SPAN copies the traffic received and transmitted by the source ports and VLANs to the destination port.

Monitored Traffic

By default, local SPAN and ERSPAN monitor all traffic, including multicast and bridge protocol data unit (BPDU) frames. RSPAN does not support BPDU monitoring.

Duplicate Traffic

In some configurations, SPAN sends multiple copies of the same source traffic to the destination port. For example, in a configuration with a bidirectional SPAN session (both ingress and egress) for two SPAN sources, called s1 and s2, to a SPAN destination port, called d1, if a packet enters the switch through s1 and is sent for egress from the switch to s2, ingress SPAN at s1 sends a copy of the packet to SPAN destination d1 and egress SPAN at s2 sends a copy of the packet to SPAN destination d1. If the packet was Layer 2 switched from s1 to s2, both SPAN packets would be the same. If the packet was Layer 3 switched from s1 to s2, the Layer 3 rewrite would alter the source and destination Layer 2 addresses, in which case the SPAN packets would be different.

Local SPAN, RSPAN, and ERSPAN Sources

These sections describe local SPAN, RSPAN, and ERSPAN sources:

•Source Ports

•Source VLANs

Source Ports

A source port is a port monitored for traffic analysis. You can configure both switched and routed ports as SPAN source ports. SPAN can monitor one or more source ports in a single SPAN session. You can configure source ports in any VLAN. Trunk ports can be configured as source ports and mixed with nontrunk source ports. SPAN does not copy the encapsulation from a source trunk port.

Source VLANs

A source VLAN is a VLAN monitored for traffic analysis. VLAN-based SPAN (VSPAN) uses a VLAN as the SPAN source. All the ports in the source VLANs become source ports.

Local SPAN, RSPAN, and ERSPAN Destination Ports

A destination port is a Layer 2 or Layer 3 LAN port to which local SPAN, RSPAN, or ERSPAN sends traffic for analysis.

When you configure a port as a destination port, it can no longer receive any traffic. When you configure a port as a destination port, the port is dedicated for use only by the SPAN feature. A SPAN destination port does not forward any traffic except that required for the SPAN session.

You can configure trunk ports as destination ports, which allows destination trunk ports to transmit encapsulated traffic. With Release 12.2(18)SXD and later releases, for local SPAN, you can configure per-VLAN filtering on destination trunk ports using allowed VLAN lists (see the "Configuring Destination Trunk Port VLAN Filtering" section).

Local SPAN, RSPAN, and ERSPAN Configuration Guidelines and Restrictions

These sections describe local SPAN, RSPAN, and ERSPAN configuration guidelines and restrictions:

•Feature Incompatiblities

•Local SPAN, RSPAN, and ERSPAN Session Limits

•Local SPAN, RSPAN, and ERSPAN Guidelines and Restrictions

•VSPAN Guidelines and Restrictions

•RSPAN Guidelines and Restrictions

•ERSPAN Guidelines and Restrictions

Note Release 12.2(18)SXE and later releases support ERSPAN.

Feature Incompatiblities

These feature incompatibilities exist with local SPAN, RSPAN, and ERSPAN:

•Egress SPAN is not supported in egress multicast mode. (CSCsa95965)

•With a PFC3, EoMPLS ports cannot be SPAN sources. (CSCed51245)

•A port-channel interface (an EtherChannel) can be a SPAN source, but you cannot configure active member ports of an EtherChannel as SPAN source ports. Inactive member ports of an EtherChannel can be configured as SPAN sources but they are put into the suspended state and carry no traffic.

•With releases earlier than Release 12.2(33)SXH, a port-channel interface (an EtherChannel) cannot be a SPAN destination.

•You cannot configure active member ports of an EtherChannel as SPAN destination ports. Inactive member ports of an EtherChannel can be configured as SPAN destination ports but they are put into the suspended state and carry no traffic.

•Because SPAN destination ports drop ingress traffic, these features are incompatible with SPAN destination ports:

–Private VLANs

–IEEE 802.1X port-based authentication

–Port security

–Spanning tree protocol (STP) and related features (PortFast, PortFast BPDU Filtering, BPDU Guard, UplinkFast, BackboneFast, EtherChannel Guard, Root Guard, Loop Guard)

–VLAN trunk protocol (VTP)

–Dynamic trunking protocol (DTP)

–IEEE 802.1Q tunneling

Note SPAN destination ports can participate in IEEE 802.3Z Flow Control.

Note IP multicast switching using egress packet replication is not compatible with SPAN. In some cases, egress replication can result in multicast packets not being sent to the SPAN destination port. If you are using SPAN and your switching modules are capable of egress replication, enter the mls ip multicast replication-mode ingress command to force ingress replication.

Local SPAN, RSPAN, and ERSPAN Session Limits

These sections describe the local SPAN, RSPAN, and ERSPAN session limits:

•PFC3

•PFC2

PFC3

These are the PFC3 local SPAN, RSPAN, and ERSPAN session limits:

Total Sessions

Local SPAN, RSPAN Source, or ERSPAN Source Sessions

RSPAN Destination Sessions

ERSPAN Destination Sessions

66

2 (ingress or egress or both)

64

23

These are the PFC3 local SPAN, RSPAN, and ERSPAN source and destination limits:

In Each Local SPAN Session

In Each RSPAN Source Session

In Each ERSPAN Source Session

In Each RSPAN Destination Session

In Each ERSPAN Destination Session

Egress or "both" sources

—

—

With releases earlier than Release 12.2(18)SXE

1

1

1

Release 12.2(18)SXE and later releases

128

128

128

Ingress sources

—

—

With releases earlier than Release 12.2(18)SXD

64

64

64

Release 12.2(18)SXD and later releases

128

128

128

RSPAN and ERSPAN destination session sources

—

—

—

1 RSPAN VLAN

1 IP address

Destinations per session

64

1 RSPAN VLAN

1 IP address

64

64

PFC2

Note•PFC2 does not support RSPAN if you configure an egress SPAN source for a local SPAN session.

•PFC2 does not support egress SPAN sources for local SPAN if you configure RSPAN.

These are the PFC2 local SPAN and RSPAN session limits:

Total Sessions

Local SPAN Sessions

RSPAN Source Sessions

RSPAN Destination Sessions

66

2 (ingress or egress or both)

0

64

1 ingress

1 (ingress or egress or both)

64

1 or 2 egress

0

64

These are the PFC2 local SPAN and RSPAN source and destination limits:

In Each Local SPAN Session

In Each RSPAN Source Session

In Each RSPAN Destination Session

Egress or "both" sources

—

With releases earlier than Release 12.2(18)SXF2

1 (0 with a remote SPAN source session configured)

1 (0 with a local SPAN egress source session configured)

Release 12.2(18)SXF2 and later releases

128

128

Ingress sources

—

With releases earlier than Release 12.2(18)SXD

64

64

Release 12.2(18)SXD and later releases

128

128

RSPAN destination session source

—

—

1 RSPAN VLAN

Destinations per session

64

1 RSPAN VLAN

64

Local SPAN, RSPAN, and ERSPAN Guidelines and Restrictions

These guidelines and restrictions apply to local SPAN, RSPAN, and ERSPAN:

•A SPAN destination port that is copying traffic from a single egress SPAN source port sends only egress traffic to the network analyzer. However, in Release 12.2(18)SXE and later releases, if you configure more than one egress SPAN source port, the traffic that is sent to the network analyzer also includes these types of ingress traffic that were received from the egress SPAN source ports:

–Any unicast traffic that is flooded on the VLAN

–Broadcast and multicast traffic

This situation occurs because an egress SPAN source port receives these types of traffic from the VLAN but then recognizes itself as the source of the traffic and drops it instead of sending it back to the source from which it was received. Before the traffic is dropped, SPAN copies the traffic and sends it to the SPAN destination port. (CSCds22021)

•Entering additional monitor session commands does not clear previously configured SPAN parameters. You must enter the no monitor session command to clear configured SPAN parameters.

•Connect a network analyzer to the SPAN destination ports.

•All the SPAN destination ports receive all of the traffic from all the SPAN sources.

Note With Release 12.2(18)SXD and later releases, you can configure destination trunk port VLAN filtering using allowed VLAN lists (see the "Configuring Destination Trunk Port VLAN Filtering" section).
With Release 12.2(18)SXE and later releases, for local SPAN and RSPAN, you can configure Source VLAN Filtering (see the "Configuring Source VLAN Filtering for Local SPAN and RSPAN" section).

•You can configure both Layer 2 LAN ports (LAN ports configured with the switchport command) and Layer 3 LAN ports (LAN ports not configured with the switchport command) as sources or destinations.

•You cannot mix individual source ports and source VLANs within a single session.

•If you specify multiple ingress source ports, the ports can belong to different VLANs.

•You cannot mix source VLANs and filter VLANs within a session. You can have source VLANs or filter VLANs, but not both at the same time.

•When enabled, local SPAN, RSPAN, and ERSPAN use any previously entered configuration.

•When you specify sources and do not specify a traffic direction (ingress, egress, or both), "both" is used by default.

•SPAN copies Layer 2 Ethernet frames, but SPAN does not copy source trunk port ISL or 802.1Q tags. You can configure destination ports as trunks to send locally tagged traffic to the traffic analyzer.

Note A destination port configured as a trunk tags traffic from a Layer 3 LAN source port with the internal VLAN used by the Layer 3 LAN port.

•Local SPAN sessions, RSPAN source sessions, and ERSPAN source sessions do not copy locally sourced RSPAN VLAN traffic from source trunk ports that carry RSPAN VLANs.

•Local SPAN sessions, RSPAN source sessions, and ERSPAN source sessions do not copy locally sourced ERSPAN GRE-encapsulated traffic from source ports.

•A port specified as a destination port in one SPAN session cannot be a destination port for another SPAN session.

•A port configured as a destination port cannot be configured as a source port.

•Destination ports never participate in any spanning tree instance. Local SPAN includes BPDUs in the monitored traffic, so any BPDUs seen on the destination port are from the source port. RSPAN does not support BPDU monitoring.

•All packets sent through the switch for transmission from a port configured as an egress source are copied to the destination port, including packets that do not exit the switch through the port because STP has put the port into the blocking state, or on a trunk port because STP has put the VLAN into the blocking state on the trunk port.

VSPAN Guidelines and Restrictions

Note Local SPAN, RSPAN, and ERSPAN all support VSPAN.

These are VSPAN guidelines and restrictions:

•For VSPAN sessions with both ingress and egress configured, two packets are forwarded from the destination port if the packets get switched on the same VLAN (one as ingress traffic from the ingress port and one as egress traffic from the egress port).

•VSPAN only monitors traffic that leaves or enters Layer 2 ports in the VLAN.

–If you configure a VLAN as an ingress source and traffic gets routed into the monitored VLAN, the routed traffic is not monitored because it never appears as ingress traffic entering a Layer 2 port in the VLAN.

–If you configure a VLAN as an egress source and traffic gets routed out of the monitored VLAN, the routed traffic is not monitored because it never appears as egress traffic leaving a Layer 2 port in the VLAN.

RSPAN Guidelines and Restrictions

These are RSPAN guidelines and restrictions:

•Supervisor Engine 2 does not support RSPAN if you configure an egress SPAN source for a local SPAN session.

•Supervisor Engine 2 does not support egress SPAN sources for local SPAN if you configure RSPAN.

•All participating switches must be trunk-connected at Layer 2.

•Any network device that supports RSPAN VLANs can be an RSPAN intermediate device.

•Networks impose no limit on the number of RSPAN VLANs that the networks carry.

•Intermediate network devices might impose limits on the number of RSPAN VLANs that they can support.

•You must configure the RSPAN VLANs in all source, intermediate, and destination network devices. If enabled, the VLAN Trunking Protocol (VTP) can propagate configuration of VLANs numbered 1 through 1024 as RSPAN VLANs. You must manually configure VLANs numbered higher than 1024 as RSPAN VLANs on all source, intermediate, and destination network devices.

•If you enable VTP and VTP pruning, RSPAN traffic is pruned in the trunks to prevent the unwanted flooding of RSPAN traffic across the network.

•RSPAN VLANs can be used only for RSPAN traffic.

•Do not configure a VLAN used to carry management traffic as an RSPAN VLAN.

•Do not assign access ports to RSPAN VLANs. RSPAN puts access ports in an RSPAN VLAN into the suspended state.

•Do not configure any ports in an RSPAN VLAN except trunk ports selected to carry RSPAN traffic.

•MAC address learning is disabled in the RSPAN VLAN.

•You can use output access control lists (ACLs) on the RSPAN VLAN in the RSPAN source switch to filter the traffic sent to an RSPAN destination.

•RSPAN does not support BPDU monitoring.

•Do not configure RSPAN VLANs as sources in VSPAN sessions.

•You can configure any VLAN as an RSPAN VLAN as long as all participating network devices support configuration of RSPAN VLANs and you use the same RSPAN VLAN for each RSPAN session in all participating network devices.

ERSPAN Guidelines and Restrictions

These are ERSPAN guidelines and restrictions:

•Release 12.2(18)SXE and later releases support ERSPAN.

•Release 12.2(18)SXF and later releases support ERSPAN when the switch is operating in any switching mode. (CSCec70695)

•Release 12.2(18)SXE and rebuilds support ERSPAN only when the switch is operating in the compact switching mode: all modules must be fabric-enabled.

•The following supervisor engines support ERSPAN:

–Supervisor engines manufactured with PFC3B and PFC3BXL support ERSPAN.

–A WS-SUP720 (a Supervisor Engine 720 manufactured with a PFC3A) can only support ERSPAN if it has hardware version 3.2 or higher. Enter the show module version | include WS-SUP720-BASE command to display the hardware version. For example:
Router# show module version | include WS-SUP720-BASE 
 7    2  WS-SUP720-BASE     SAD075301SZ Hw :3.2
–To confirm that your supervisor engine supports ERSPAN, enter the show asic-version slot slot_number | include ASIC|HYPERION command for the supervisor engine. For example:
Router# show asic-version slot 1 | include ASIC|HYPERION 
Module in slot 1 has 2 type(s) of ASICs
        ASIC Name      Count      Version
         HYPERION          1      (6.0)
Hyperion version 2.0 and higher supports ERSPAN.

•Supervisor engine 2 does not support ERSPAN.

•For ERSPAN packets, the "protocol type" field value in the GRE header is 0x88BE.

•The payload of a Layer 3 ERSPAN packet is a copied Layer 2 Ethernet frame, excluding any ISL or 802.1Q tags.

•ERSPAN adds a 50-byte header to each copied Layer 2 Ethernet frame and replaces the 4-byte cyclic redundancy check (CRC) trailer.

•ERSPAN supports jumbo frames that contain Layer 3 packets of up to 9,202 bytes. If the length of the copied Layer 2 Ethernet frame is greater than 9,170 (9,152-byte Layer 3 packet), ERSPAN truncates the copied Layer 2 Ethernet frame to create a 9,202-byte ERSPAN Layer 3 packet.

•Regardless of any configured MTU size, ERSPAN creates Layer 3 packets that can be as long as 9,202 bytes. ERSPAN traffic might be dropped by any interface in the network that enforces an MTU size smaller than 9,202 bytes.

•With the default MTU size (1,500 bytes), if the length of the copied Layer 2 Ethernet frame is greater than 1,468 bytes (1,450-byte Layer 3 packet), the ERSPAN traffic is dropped by any interface in the network that enforces the 1,500-byte MTU size.

Note The mtu interface command and the system jumbomtu command (see the "Configuring Jumbo Frame Support" section on page 9-10) set the maximum Layer 3 packet size (default is 1,500 bytes, maximum is 9,216 bytes).

•All participating switches must be connected at Layer 3 and the network path must support the size of the ERSPAN traffic.

•ERSPAN does not support packet fragmentation. The "do not fragment" bit is set in the IP header of ERSPAN packets. ERSPAN destination sessions cannot reassemble fragmented ERSPAN packets.

•ERSPAN traffic is subject to the traffic load conditions of the network. You can set the ERSPAN packet IP precedence or DSCP value to prioritize ERSPAN traffic for QoS.

•The only supported destination for ERSPAN traffic is an ERSPAN destination session on a PFC3.

•All ERSPAN source sessions on a switch must use the same origin IP address, configured with the origin ip address command (see the "Configuring ERSPAN Source Sessions" section).

•All ERSPAN destination sessions on a switch must use the same IP address on the same destination interface. You enter the destination interface IP address with the ip address command (see the "Configuring ERSPAN Destination Sessions" section).

•The ERSPAN source session's destination IP address, which must be configured on an interface on the destination switch, is the source of traffic that an ERSPAN destination session sends to the destination ports. You configure the same address in both the source and destination sessions with the ip address command.

•The ERSPAN ID differentiates the ERSPAN traffic arriving at the same destination IP address from various different ERSPAN source sessions.

Configuring Local SPAN, RSPAN, and ERSPAN

These sections describe how to configure local SPAN, RSPAN, and ERSPAN:

•Configuring Destination Port Permit Lists (Optional)

•Configuring Local SPAN

•Configuring RSPAN

•Configuring ERSPAN

•Configuring Source VLAN Filtering for Local SPAN and RSPAN

•Configuring a Destination Port as an Unconditional Trunk

•Configuring Destination Trunk Port VLAN Filtering

•Verifying the Configuration

•Configuration Examples

Configuring Destination Port Permit Lists (Optional)

To prevent accidental configuration of ports as destinations, you can create a permit list of the ports that are valid for use as destinations. With a destination port permit list configured, you can only configure the ports in the permit list as destinations.

To configure a destination port permit list, perform this task:

Command

Purpose

Step 1

Router# configure terminal

Enters global configuration mode.

Step 2

Router(config)# monitor permit-list

Enables use of the destination port permit list.

Step 3

Router(config)# no monitor permit-list

Disables use of the destination port permit list.

Step 4

Router(config)# monitor permit-list destination interface type¹ slot/port[-port] [, type1 slot/port - port]

Configures a destination port permit list or adds to an existing destination port permit list.

Step 5

Router(config)# no monitor permit-list destination interface type1 slot/port[-port] [, type1 slot/port - port]

Deletes from or clears an existing destination port permit list.

Step 6

Router(config)# do show monitor permit-list

Verifies the configuration.

¹type = ethernet, fastethernet, gigabitethernet, or tengigabitethernet

This example shows how to configure a destination port permit list that includes Gigabit Ethernet ports 5/1 through 5/4 and 6/1:
Router# configure terminal 
Router(config)# monitor permit-list 
Router(config)# monitor permit-list destination interface gigabitethernet 5/1-4, 
gigabitethernet 6/1 
This example shows how to verify the configuration:
Router(config)# do show monitor permit-list 
 SPAN Permit-list      :Admin Enabled
 Permit-list ports     :Gi5/1-4,Gi6/1
Configuring Local SPAN

Local SPAN does not use separate source and destination sessions. To configure a local SPAN session, configure local SPAN sources and destinations with the same session number. To configure a local SPAN session, perform this task:

Command

Purpose

Step 1

Router# configure terminal

Enters global configuration mode.

Step 2

Router(config)# monitor session local_span_session_number source {{single_interface | interface_list | interface_range | mixed_interface_list | single_vlan | vlan_list | vlan_range | mixed_vlan_list} [rx | tx | both]}}

Associates the local SPAN source session number with the source ports or VLANs and selects the traffic direction to be monitored.

Step 3

Router(config)# monitor session local_span_session_number destination {single_interface | interface_list | interface_range | mixed_interface_list}

Associates the local SPAN session number and the destination ports.

Router(config)# no monitor session {session_number | all | local | range session_range[[,session_range],...]}

Clears the monitor configuration.

When configuring local SPAN sessions, note the following information:

•local_span_session_number can range from 1 to 66.

•single_interface is interface type slot/port; type is ethernet, fastethernet, gigabitethernet, or tengigabitethernet.

•interface_list is single_interface , single_interface , single_interface ...

Note In lists, you must enter a space before and after the comma. In ranges, you must enter a space before and after the dash.

•interface_range is interface type slot/first_port - last_port.

•mixed_interface_list is, in any order, single_interface , interface_range , ...

•single_vlan is the ID number of a single VLAN.

•vlan_list is single_vlan , single_vlan , single_vlan ...

•vlan_range is first_vlan_ID - last_vlan_ID.

•mixed_vlan_list is, in any order, single_vlan , vlan_range , ...

•To tag the monitored traffic as it leaves a destination port, you must configure the destination port to trunk unconditionally before you configure it as a destination (see the "Configuring a Destination Port as an Unconditional Trunk" section).

When clearing monitor sessions, note the following information:

•The no monitor session number command entered with no other parameters clears session session_number.

•session_range is first_session_number-last_session_number.

Note In the no monitor session range command, do not enter spaces before or after the dash. If you enter multiple ranges, do not enter spaces before or after the commas.

This example shows how to configure Fast Ethernet port 5/1 as a bidirectional source for session 1:
Router(config)# monitor session 1 source interface fastethernet 5/1 
This example shows how to configure Fast Ethernet port 5/48 as the destination for SPAN session 1:
Router(config)# monitor session 1 destination interface fastethernet 5/48 
For additional examples, see the "Configuration Examples" section.

Configuring RSPAN

RSPAN uses a source session on one switch and a destination session on a different switch. These sections describe how to configure RSPAN sessions:

•Configuring RSPAN VLANs

•Configuring RSPAN Source Sessions

•Configuring RSPAN Destination Sessions

Configuring RSPAN VLANs

To configure a VLAN as an RSPAN VLAN, perform this task:

Command

Purpose

Step 1

Router# configure terminal

Enters global configuration mode.

Step 2

Router(config)# vlan vlan_ID{[-vlan_ID]|[,vlan_ID])

Creates or modifies an Ethernet VLAN, a range of Ethernet VLANs, or several Ethernet VLANs specified in a comma-separated list (do not enter space characters).

Step 3

Router(config-vlan)# remote-span

Configures the VLAN as an RSPAN VLAN.

Router(config-vlan)# no remote-span

Clears the RSPAN VLAN configuration.

Step 4

Router(config-vlan)# end

Updates the VLAN database and returns to privileged EXEC mode.

Configuring RSPAN Source Sessions

To configure an RSPAN source session, perform this task:

Command

Purpose

Step 1

Router# configure terminal

Enters global configuration mode.

Step 2

Router(config)# monitor session RSPAN_source_session_number source {{single_interface | interface_list | interface_range | mixed_interface_list | single_vlan | vlan_list | vlan_range | mixed_vlan_list} [rx | tx | both]}}

Associates the RSPAN source session number with the source ports or VLANs, and selects the traffic direction to be monitored.

Step 3

Router(config)# monitor session RSPAN_source_session_number destination remote vlan rspan_vlan_ID

Associates the RSPAN source session number session number with the RSPAN VLAN.

Step 4

Router(config)# no monitor session {session_number | all | range session_range[[,session_range],...] | remote}

Clears the monitor configuration.

When configuring monitor sessions, note the following information:

•To configure RSPAN VLANs, see the "Configuring RSPAN VLANs" section.

•RSPAN_source_span_session_number can range from 1 to 66.

•single_interface is interface type slot/port; type is ethernet, fastethernet, gigabitethernet, or tengigabitethernet.

•interface_list is single_interface , single_interface , single_interface ...

Note In lists, you must enter a space before and after the comma. In ranges, you must enter a space before and after the dash.

•interface_range is interface type slot/first_port - last_port.

•mixed_interface_list is, in any order, single_interface , interface_range , ...

•single_vlan is the ID number of a single VLAN.

•vlan_list is single_vlan , single_vlan , single_vlan ...

•vlan_range is first_vlan_ID - last_vlan_ID.

•mixed_vlan_list is, in any order, single_vlan , vlan_range , ...

When clearing monitor sessions, note the following information:

•The no monitor session number command entered with no other parameters clears session session_number.

•session_range is first_session_number-last_session_number.

Note In the no monitor session range command, do not enter spaces before or after the dash. If you enter multiple ranges, do not enter spaces before or after the commas.

This example shows how to configure Fast Ethernet port 5/2 as the source for session 2:
Router(config)# monitor session 2 source interface fastethernet 5/2 
This example shows how to configure RSPAN VLAN 200 as the destination for session 2:
Router(config)# monitor session 2 destination remote vlan 200 
For additional examples, see the "Configuration Examples" section.

Configuring RSPAN Destination Sessions

Note You can configure an RSPAN destination session on the RSPAN source session switch to monitor RSPAN traffic locally.

To configure an RSPAN destination session, perform this task:

Command

Purpose

Step 1

Router# configure terminal

Enters global configuration mode.

Step 2

Router(config)# monitor session RSPAN_destination_session_number source remote vlan rspan_vlan_ID

Associates the RSPAN destination session number with the RSPAN VLAN.

Step 3

Router(config)# monitor session RSPAN_destination_session_number destination {single_interface | interface_list | interface_range | mixed_interface_list}}

Associates the RSPAN destination session number with the destination ports.

Step 4

Router(config)# no monitor session {session_number | all | range session_range[[,session_range],...] | remote}

Clears the monitor configuration.

When configuring monitor sessions, note the following information:

•To tag the monitored traffic, you must configure the port to trunk unconditionally before you configure it as a destination (see the "Configuring a Destination Port as an Unconditional Trunk" section).

•RSPAN_destination_span_session_number can range from 1 to 66.

•single_interface is interface type slot/port; type is ethernet, fastethernet, gigabitethernet, or tengigabitethernet.

•interface_list is single_interface , single_interface , single_interface ...

Note In lists, you must enter a space before and after the comma. In ranges, you must enter a space before and after the dash.

•interface_range is interface type slot/first_port - last_port.

•mixed_interface_list is, in any order, single_interface , interface_range , ...

When clearing monitor sessions, note the following information:

•Enter the no monitor session number command with no other parameters to clear session session_number.

•session_range is first_session_number-last_session_number.

Note In the no monitor session range command, do not enter spaces before or after the dash. If you enter multiple ranges, do not enter spaces before or after the commas.

This example shows how to configure RSPAN VLAN 200 as the source for session 3:
Router(config)# monitor session 3 source remote vlan 200 
This example shows how to configure Fast Ethernet port 5/47 as the destination for session 3:
Router(config)# monitor session 3 destination interface fastethernet 5/47 
For additional examples, see the "Configuration Examples" section.

Configuring ERSPAN

ERSPAN uses separate source and destination sessions. You configure the source and destination sessions on different switches. These sections describe how to configure ERSPAN sessions:

•Configuring ERSPAN Source Sessions

•Configuring ERSPAN Destination Sessions

Note With a PFC3, Release 12.2(18)SXE and later releases support ERSPAN (see the "ERSPAN Guidelines and Restrictions" section).

Configuring ERSPAN Source Sessions

To configure an ERSPAN source session, perform this task:

Command