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New Member

Adding switch in to production network

Hi all,

I have to add a new switch in production network and want to keep this switch isolated from existing network.

But for management purpose- i have to connect to exisiting network so that i can extend management vlan from current switch to new switch.

Current switch in VTP domain so do  i need to configur new switch in VTP domain because i just want to extend management vlan no other vlan should prpogate to this switch.

and do i need to do somthing for STP so that it won't create any loop.




Adding switch in to production network

Is this new switch going to be a replacement for the new switch, or are you just adding a new switch?

What you could do is, setup the specific VTP domain on the new switch, and set the mode to transparent.

You could then, configure the trunk to only allow the management vlan. So the only vlans that will go across

the trunk will be the management vlan and the native vlan, or if they are the same than just that one.

Then, once you are ready to put it in productiont, you can change the mode to vtp client, and manually configure

the trunks to allow only specific vlans you want across the trunk.

Also, by just adding another switch you are most likely not going to cause a switching loop. Spanning

Tree should prevent this, but just take a look at your switching topology. If the new switch has a shorter

path to the root switch than, there could be some recalculation's going on.

New Member

Adding switch in to production network

Thanks John,

is it necessary to allow native vlan also ?

after adding this switch we can not leave this switch as transparent mode- so that it wont learn any chnages made on other existing switches because i want to make this switch isolated from exsiting network except management vlan.



Adding switch in to production network

You don't need to add the native vlan, it will be there by default. Even if you type "show int trunk", and don't see the native

vlan listed, it will still be there. I understand about the transparent/vtp deal you are talking about. If you don't want to leave it there it's fine, just put it back whenever you want.