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Troubleshooting Switched Connections
603
Note that traffic may be monitored on the receive or transmit channels, or
both. The administrator may select to mirror a single port within the VLAN or
have all traffic within the VLAN copied onto the mirroring port. It is important for
the administrator to understand the problem's scope and the network topology
before attempting to troubleshoot problems with the SPAN function.
The Route Switch Module and Catalyst Routing
The route switch module, or RSM, is a Cisco router on a card within the Cat-
alyst chassis. This card may be configured to provide routing between
VLANs. With an external router, companies often incur additional expense
and complexity--the RSM virtually attaches to VLANs, and as such does
not occupy a port as an ISL or 802.1q-linked external router would. Of
course, there are times when an external router is required. The performance
of the 7513 is faster and a greater number of interface types are supported.
However, when combined with the NetFlow Feature Card (NFFC or NFFC
II), the RSM and Catalyst can provide powerful Layer 2 and 3 switching.
The configuration of the RSM is very similar to the Cisco router platform.
As shown in the following output, the router module supports IOS features,
including password encryption and HSRP. Note that the interfaces are defined
as VLAN1 and VLAN2. Unlike the router, the RSM is virtually connected to
the VLANs via the backplane. This connection is 400Mbit half-duplex.
To connect to the RSM, administrators typically connect to the Supervisor
engine CLI and use the session command to attach to the RSM. For example,
if the RSM card were in slot 4, the command would read session 4.
Building configuration...
Current configuration:
!
version 11.3
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
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