3750X Stack Problems

jamal.pruden · ‎08-14-2013

A colleague of mine powered on a 3750X switch and added it to an existing stack before the stack finished booting. Now, it seems as though the switch is in a continous loop. Here is what I have done to try to resolve the issue:

- reload the entire stack.

- remove the switch from the stack and boot up as a stand alone (switch is ok).

- connect the stack wise cables on the new switch and add power (stack joins and then is removed).

- delete all configuration from the new switch and attempt to add (again, the switch is added and removed).

All 3 devices are running the same IOS.

Any help is appreciated.

Reza Sharifi · ‎08-14-2013

Do all the switches have the same license level?

Can you manually prevision the switch in the current stack before adding the 3rd one?

switch 3 prov type?

HTH

jamal.pruden · ‎08-14-2013

Hi Reza,

Yes, all 3 have the same license level.

Originally, the switch was provisioned as switch 4, but I changed to switch 3 and still no luck.

Reza Sharifi · ‎08-14-2013

Hi Jamal,

Can you make sure the stacking cable is all the way in its socket? I have noticed that you have to push it all the way in and screw it to keep it tight.

HTH

jamal.pruden · ‎08-14-2013

Hi Reza,

Yes, I made sure (several times) the cables were attached securely.

Leo Laohoo · ‎08-14-2013

A colleague of mine powered on a 3750X switch and added it to an existing stack before the stack finished booting.

This is the cause of the issue.

The correct proceedure to add a new switch to a stack is to ensure the new stack member is POWERED OFF, connect the stacking cable and then power up the switch.

When you power up the new stack member and then connect the stacking cable, the entire stack will reboot. This is because the entire stack will go into a stack election. This behaviour is to be expected.

jamal.pruden · ‎08-15-2013

Hi Leo,

Not sure if this is accurate. The priority has been set on one switch to 5 to make sure that that particular switch remains the master. The other two are set at 1, so they will be slaves. The switch being added is in a loop while the other two are fine.

Regards

Leo Laohoo · ‎08-15-2013

Not sure if this is accurate.  The priority has been set on one switch to 5 to make sure that that particular switch remains the master.  The other two are set at 1, so they will be slaves.  The switch being added is in a loop while the other two are fine.

Hi Jamal,

Yes, what I stated IS accurate. It doesn't matter if you've configured switch priority or not. As long as the new switch is already powered up, as soon as you connect the first pair of stacking cable, the entire stack will reboot. This is a normal behaviour.