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| 9.2 |  | RSPAN |
| 9.2.4 |  | RSPAN and RSPAN VLANs |

The following restrictions apply when configuring SPAN and RSPAN sessions on a 2950 series switch:

- There is a limit of one active source session for either SPAN or RSPAN.
- A 2950 switch cannot support both SPAN and RSPAN source processes simultaneously.
- RSPAN source sessions have one destination per session with an RSPAN VLAN associated for that session.
- Each RSPAN destination session has one or more destination interfaces for each RSPAN VLAN that they support.
- RSPAN destination sessions are limited to two, or one if a local SPAN or a source RSPAN session is configured on the same switch.

On a 3550 series switch, a maximum of two SPAN or RSPAN sessions can be configured and stored in NVRAM on each switch. The two sessions can be divided between SPAN, RSPAN source, and RSPAN destination sessions. Multiple source ports or source VLANs can be configured for each session.

The 6500 series switch, configured as an RSPAN source switch, can support up to 30 RSPAN destination sessions.

In a network consisting of only Catalyst 2950 series switches, each RSPAN source switch should be configured with a unique RSPAN VLAN. If two or more switches use the same RSPAN VLAN, they can act only as RSPAN source switches to ensure the delivery of all monitored traffic to the RSPAN destination switch.

Any VLAN on either the Catalyst 2950 series or 3550 series switch can be configured as an RSPAN VLAN as long as the following conditions are met:

- The RSPAN VLAN cannot be configured as a native VLAN on a Catalyst 2950 series switch.
- Extended range RSPAN VLANs configured on a Catalyst 2950 series switch will not be propagated to other switches using VTP.
- No access port is configured in the RSPAN VLAN.
- All participating switches support RSPAN.
- The same RSPAN VLAN is used for an RSPAN session in all Catalyst 3550 series switches.

An RSPAN VLAN (a VLAN reserved for use by RSPAN) should be created and propagated through the switch network before an RSPAN source or destination session is configured. If VTP is enabled in the network, the RSPAN VLAN can be created on a single VTP server switch, and will be propagated to other VTP switches in the VTP domain. If VTP pruning is also enabled, RSPAN traffic is pruned by the VLAN trunks to prevent any unwanted flooding of RSPAN traffic across the network for VLAN-IDs lower than 1005.