8-4
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Chapter 8 Configuring SDM Templates
Configuring the Switch SDM Template
This is an example of a syslog message notifying the stack master that a stack member is in SDM
mismatch mode:
2d23h:%STACKMGR-6-SWITCH_ADDED_SDM:Switch 2 has been ADDED to the stack (SDM_MISMATCH)
2d23h:%SDM-6-MISMATCH_ADVISE:
2d23h:%SDM-6-MISMATCH_ADVISE:
2d23h:%SDM-6-MISMATCH_ADVISE:System (#2) is incompatible with the SDM
2d23h:%SDM-6-MISMATCH_ADVISE:template currently running on the stack and
2d23h:%SDM-6-MISMATCH_ADVISE:will not function unless the stack is
2d23h:%SDM-6-MISMATCH_ADVISE:downgraded. Issuing the following commands
2d23h:%SDM-6-MISMATCH_ADVISE:will downgrade the stack to use a smaller
2d23h:%SDM-6-MISMATCH_ADVISE:compatible desktop SDM template:
2d23h:%SDM-6-MISMATCH_ADVISE:
2d23h:%SDM-6-MISMATCH_ADVISE: "sdm prefer vlan desktop"
2d23h:%SDM-6-MISMATCH_ADVISE: "reload"
Configuring the Switch SDM Template
These sections contain this configuration information:
• Default SDM Template, page 8-4
• SDM Template Configuration Guidelines, page 8-4
• Setting the SDM Template, page 8-5

Default SDM Template

The default template is the default Switch Database Management (SDM) desktop template.

SDM Template Configuration Guidelines

• When you configure a new SDM template, you must reload the switch for the configuration to take
effect.
• On switches running the IP base or IP services feature set, use the sdm prefer vlan global
configuration command only on switches intended for Layer 2 switching with no routing.
When you use the VLAN template, no system resources are reserved for routing entries, and any
routing is done through software. This overloads the CPU and severely degrades routing
performance.
• Do not select a routing template (sdm prefer routing or sdm prefer dual-ipv4-and-ipv6 routing)
when the switch is running the LAN base feature set. Although visible in the command-line help,
the LAN base feature set does not support routing. On switches running the LAN base feature set,
routing values shown in all templates are not valid.
• Do not use the routing template if you do not have routing enabled on your switch. To prevent other
features from using the memory allocated to unicast routing in the routing template, use the sdm
prefer routing global configuration command.
• If you try to configure IPv6 without first selecting a dual IPv4 and IPv6 template, a warning message
appears.
• Using the dual stack template results in less hardware capacity allowed for each resource, so do not
use it if you plan to forward only IPv4 traffic.