Information Technology Reference
In-Depth Information
•
CatOS
—Look for the field RsrcErrors (resource error) in the output of
show inband
(on some
supervisors, this command is hidden under the name
show biga
). Basically, this counter is
incremented when the processor was too overloaded to perform some of its tasks. There is a
limitation on the number of different instances of STP that a supervisor engine can handle. Check
the release notes of the software that you are running for this.
The following is a summary of the restrictions that apply to the Catalyst 4000/5000/6000 series:
Ensure that the total number of logical ports across all instances of STP for
different VLANs does not exceed the maximum number supported for each
supervisor engine type and memory configuration. You can use the
show spantree
summary
command and this formula to compute the sum of logical ports on the
switch:
(number of non-ATM trunks
´
number of active VLANs on that trunk)
+ 2*(number of ATM trunks
number of active VLANs on that trunk)
+ number of nontrunking ports.
The sum of all logical ports, as calculated with this formula, should be less than or
equal to:
For the Catalyst 4000 series:
•
1500 for the Catalyst 4000 family Supervisor Engine I and II
For the Catalyst 5000 series:
•
200 for Supervisor Engine I (with 8-MB DRAM)
•
400 for Supervisor Engine I (with 20-MB DRAM)
•
1500 for Supervisor Engine II and III F
•
1800 for Supervisor Engine II G and III G
•
4000 for Supervisor Engine III
For the Catalyst 6000 series:
•
´
4000 for Supervisor
Disable Unneeded Features
Troubleshooting is a matter of identifying what is currently wrong in the network. In this regard,
disabling as many features as possible helps to simplify the network structure and eases the identification
of the problem. EtherChanneling, for instance, is an advanced feature that needs STP to logically bundle
several different links into a single one. It makes sense to disable this feature during a troubleshooting
period. Again, this is just an example, but generally, going to a configuration as simple as possible
reduces the troubleshooting effort.
Useful Commands
This section lists useful commands for the Catalyst IOS and the Catalyst OS.
Catalyst IOS Commands
show interface
