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Stack problem with Cisco 3750 switches

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Dave151

Technical User
Apr 29, 2005
14
GB


Problem with Cisco 3750-24ps-s switches



Two ws-c3750-24p have been stacked together as one switch using a cluster command.



switch 1 provision ws-c3750-24p
switch 2 provision ws-c3750-24p
ip subnet-zero
ip routing
!
cluster enable Exeter_Cluster 0



Have rebooted the switch stack and now ports 1/1 - 24 are down down status and under show interface status the ports are not visable, only the up up ports 2/1 - 24 are viable.

Under show CDP neighbor doesn't recognise anything other than devices plugged into the ports 2/1 - 24.

Everytime I reboot the switches only ports 2/1 - 24 come up.

Can't get the switches to stack as one although show run lists both switch ports

 
If you have the switches connected via their backbone stacking cables then you don't need the cluster command.
 
When is the cluster command used?

If I remove it I lose sight of the switch who's ports are down?

This is a remote branch which a former colleague set up so I assumed he cascaded the two
 
I suggest you disconnect the stacking cables, default the config on both of them and then reconnect and power them up. Then configure from scratch. As braidninms said you don't need the cluster command, this was used for 'psuedo' stacking with 2900xl/3500xl's, 2950's etc to make an ethernet-connected 'stack' of switches manageable from the same IP address. It was pretty rubbish if I remember correctly, stay away from it, and if you follow Cisco's design best practises you won't have a common VLAN between any access switches anyway.

Andy
 
Thanks for the advice thought it would be a case of starting a fresh. Looks like a four hour drive tomorrow!
 
Check in the logg , its possible you have a version mismatch between both switches keeping the other from coming up , it should tell you this in the log. Do a dir flash all and see if both flashes from both switches shows up . If so you may be able to copy from the the device that is up to the other 3750 and then reload again . Also make sure that the boot statement is correct , should be like "boot system switch-all flash:<imagename> or something close to that . To see if the switches are actually stacked via the backplane cables just do a "show switch detail command and you should see 2 switches and how they are cables together.
 
'show switch detail' only shows one of the switches.

One of my colleagues is on site and consoled on to the problem switch he got the messege 'switch is not usable'. Any idea's what caused this? Corrupt IOS?

He tried erasing config and rejoining it to the stack but no joy.

We've swapped out the switch for a like for like using the cascade cables to stack them and all fine. 'Show switch detail' can now see both switches with one as master.

Everything back and working, only question is what caused the switch to fail?

Thanks everyone for your help.
 
Was the switch new? Could be that it just died and needs to be RMD'd.
 
Was the switch new? Could be that it just died and needs to be RMA'd.
 
HA! Double-post for the win.

Can you delete posts here?
 
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