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3750 Switch Priority

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12523403750 Operational Notes: Stack Master Settings

The stack master is the single point of stack-wide management. From the stack master, you configure:

- System-level (global) features that apply to all stack members
- Interface-level features for each stack member

All stack members are eligible stack masters. If the stack master becomes unavailable, the remaining stack members participate in electing a new stack master from among themselves. A set of factors determine which switch is elected the stack master. One of the factors is the stack member priority value. The switch with the highest priority value becomes the stack master.

A higher priority value for a stack member increases its likelihood to be elected stack master and to retain its stack member number. The priority value can be 1 to 15. The default priority value is 1.

Last Updated on Friday, 06 July 2012 11:34

Cisco - Switch Notes

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Show Flash - Useful when configuring switch setup:


A sh flash shows


2  -rwx        6051  Jan 11 2010 18:15:10 +00:00  config.text
4  -rwx         676   Jan 8 1994 02:35:40 +00:00  vlan.dat
5  drwx         192   Mar 1 1993 00:12:17 +00:00  c3750-ipservices-mz.122-25.SEE3
458  -rwx         512  May 23 2010 18:24:03 +00:00


Notice the You may also see private-config.text.backup and/or config.text.backup. These may be there due to the switch being previously managed.

Along with the config.text you may need to write the text file.

There are a number of ways to write:

Last Updated on Monday, 29 August 2011 15:30

Cisco - Show Interface Desciption

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Need to find a port desciption?

sh int desc OR show interface description

This is not a well documented command and can really come in handy trying to find desciptions of ports.

Especially on a 48 port switch....


Last Updated on Monday, 18 July 2011 13:16

Cisco Switch Stack - Default Setup

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How to default a once stacked Cisco 3750 to a single switch


You need to provision it as an stand alone switch:

use this command:


Switch-B(config)#switch 1 provision <switch type)


If the switch was number 2 in the stack this command will make it one.


There is more to this story...

In order to get a switch back to position 1 you have to complete this in a few steps.

Otherwise you will still see the newly appointed switch 1 and the old position with all ports showing...

                     switch [current stack number] renumber 1

Then once you have the switch renumbered do a sh ip int brief    <3750(config)#show ip interface brief>

You will see 24 or 48 ports in both positions. In my case I had a switch 3 and moved to 1 and completing the sh ip int brief will show both positions.

Now you can removed the orphan position, in my case I needed to remove position 3 on a 48 port 3750.

<3750(config)# no switch 3 provision ws-c3750-48p>
<3750(config)# exit>
<3750# write memory >

This works.... I originally used the first method however if you try this you will see what I mean about keeping the original switch position.

It will still show ports on the old number and new....



Last Updated on Wednesday, 20 July 2011 06:34

Port Monitoring Cisco 3750

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SPAN on the Catalyst 2940, 2950, 2955, 2960, 2970, 3550, 3560, 3560-E, 3750 and 3750-E Series Switches

These are guidelines for the configuration of the SPAN feature on the Catalyst 2940, 2950, 2955, 2960, 2970, 3550, 3560, 3560-E, 3750, and 3750-E Series Switches:

  • The Catalyst 2950 Switches can have only one SPAN session active at a time and can monitor only source ports. These switches cannot monitor VLANs.

  • The Catalyst 2950 and 3550 Switches can forward traffic on a destination SPAN port in Cisco IOS Software Release 12.1(13)EA1 and later.
Last Updated on Sunday, 17 July 2011 13:22