Cisco Stack switch renumber ; impact on interface config

[Jay47110]

Hi,

I have a question regarding Cisco Stack wise switch renumbering.

I have a couple of C2960X stack switches (number 2 and 3) and I want to renumber of the switches in the stack from i.e. from 3 to 1 using 

# switch 3 renumber 1

I understand the stack member will need to be rebooted for the renumbering to take effect. However, does renumbering have any impact on the interface configuration? i.e. would the config on the now switch 1 interfaces remain as is or will it be cleared of all config after reboot?

Kind regards

[balaji.bandi]

yes correct, you need to keep that in mind , if you alrady have number 1 (you need to renumber before you make switch3 to be number 1)

reload will change the port-number

exampple : if the device connected 3/0/1 after renumber it going to be 1/0/1

[Jay47110]

Hi,

Just to clarify, you confirm that the interface config will be wiped out after renumbering and reboot?

There is no Switch1 in the stack, so switch 3 renumbering to 1 should be ok.

Kind regards

[balaji.bandi]

Config was not going to be wiped, but switch port numbering changes. ( as i have given example ?)

There is no Switch1 in the stack,

this is strange, without switch1 how one build stack, default is switch 1

worth checking show switch command before you make any changes (if this live make sure you do in maintenance window).

[Jay47110]

Thanks Bajali,

Thanks for confirming that interface config will remain intact after reboot.
Yes, there is no switch1 in the stack, I'm guessing it was removed from the stack in the past and switch 3 has since become the master.

Switch# Role            Mac Address   Priority Version State

2           Member   94d4.697e.6d80  1          4       Ready

*3         Master      00b0.e13d.7780  1          4       Ready

Kind regards

[balaji.bandi]

when you doing renumbering suggest to change the priority of the switch to so it become master all time.,

In terms of config, if all the ports have same config access port, that should not be matter.

but take example :

if the config gi 3/0/1 VLAN 10   gi 3/0/2 vlan 30

when you move to switch 1, the config will be not the same.

so better take the config backup (for safe side) - once switch reboot - you may change the config accordingly.

Same this applies to uplink ports.

[Jay47110]

Thanks B,

We will set the priority as well.

I'm a bit confused regarding interface config change post reboot.

There are trunk uplinks including mgmt and other access + VOIP links on Switch3. You are saying that all that config will be lost? If thats the case then I will arrange for OOB access then.

If possible, please clarify what exaxtly does change when switch is renumbered and rebooted.

Kind regards

.

[balaji.bandi · Accepted solution]

See the config save in NVRAM refering port config 3/0/1 (example trunk)

when you change the number from switch 3 to switch1  ( the information not available gi 1/0/1 - so that will be empty config)

I do not believe switch is so intellegent to change the config also if the port-number changed.

So you need to  be aware this information, make sense ?

[Jay47110]

Thanks for the help mate

[Tomáš Šupa]

The port configuration remains the same => If port Gi1/0/1 was configured as a trunk, it will be a trunk after this renumber/reload. You just have to change the priority of the switch after reload.