49-12
Catalyst 6500 Series Switch Software Configuration Guide—Release 8.7
OL-8978-04
Chapter 49 Configuring SPAN, RSPAN and the Mini Protocol Analyzer
Configuring RSPAN on the Switch
•
Each Catalyst 6500 series switch can source a maximum of one RSPAN session (ingress, egress, or
both). When you configure a remote ingress or bidirectional SPAN session in a source switch, the
limit for the local ingress or bidirectional SPAN sessions is reduced to one. There are no limits on
the number of RSPAN sessions that are carried across the network within the RSPAN session limits
(see the
“SPAN, RSPAN and Mini Protocol Analyzer Session Limits” section on page 49-5
).
•
The RSPAN VLANs cannot be included as the sources for the port-based RSPAN sessions when the
source trunk ports have active RSPAN VLANs. Additionally, the RSPAN VLANs cannot be the
sources in the VSPAN sessions.
•
You can configure any VLAN as an RSPAN VLAN if these conditions are met:
–
The same RSPAN VLAN is used for an RSPAN session in all the switches.
–
All participating switches have the appropriate hardware and software.
–
No access port (including the sc0 interface) is configured in the RSPAN VLAN.
•
If you enable VTP and VTP pruning, the RSPAN traffic is pruned in the trunks to prevent the
unwanted flooding of the RSPAN traffic across the network.
•
If you enable the GARP VLAN Registration Protocol (GVRP) and the GVRP requests conflict with
the existing RSPAN VLANs, you might observe unwanted traffic in the RSPAN sessions.
•
You can use the RSPAN VLANs in Inter-Switch Link (ISL) to dot1q mapping. However, ensure that
the special properties of RSPAN VLANs are supported in all the switches to avoid the unwanted
traffic in these VLANs.
Configuring RSPAN
The first step in configuring an RSPAN session is to select an RSPAN VLAN for the RSPAN session that
does not
exist in any of the switches that will participate in RSPAN. With VTP enabled in the network,
you can create the RSPAN VLAN in one switch and VTP propagates it to the other switches in the VTP
domain.
Use VTP pruning to get an efficient flow of RSPAN traffic, or manually delete the RSPAN VLAN from
all trunks that do not need to carry the RSPAN traffic.
Once the RSPAN VLAN is created, you configure the source and destination switches by entering the
set rspan
command.
To configure the RSPAN VLANs, perform this task in privileged mode:
Task
Command
Step 1
Configure the RSPAN VLANs.
set vlan
vlan
[
rspan
]
Step 2
Verify the RSPAN VLAN configuration.
show vlan