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New Member

STP changes

If i add the new switches in exisiting stp topology will it affect network outage. i.e. i have already one root switch i am just adding one more access layer switch into distriction switch..

appriciate your feedback..

New Member

Re: STP changes

Hello kamal,

remember that when you power on a brand new switch, the VTP will be in server mode. as soon as you plug it into the network,. there every chance, you mite run into issues assuming you do have a VTP domain and assuming you have Dynamic VLANS.

So the best practice is always to have your vtp mode set to transparent ( if your design allows it ) or to set it to client ( again if thats what your design requires) and then its also a good idea to keep all the vlans except for the management vlan in shut down state and then socialise the new switch to your network if you were to do it in a production environment.

otherwise its always a good idea to socialise it out of hours just to ensure network continuity and service integrity.

rate it if you are happy with it.



Re: STP changes

Hello Kamal,

in addition to Sidd's post, just make sure that you reset the revision number of the switch you want to add to 0. The best way to do this is to configure the switch for VTP transparent mode, and then back to client mode.

The following applies:

Be aware that if a new switch is attached to an existing VTP domain and the new switch has the same VTP domain and has a VLAN database configuration revision that is higher than that which is currently present in the existing network, the existing VLAN database is overwritten with the VLAN database on the new switch, regardless of whether the switch is a VTP server or client.

Other than that, there should not really be an issue with adding the switch.



New Member

Re: STP changes

Hi Guys,

Thanks for your feedback. I am really tought able this. but my concern will it affect stp topology converge. is that any outage will be there..

Re: STP changes

Hie Kamal,

As far as STP is concerned, there should not be any outage if you are adding an access switch. I hope you have lower configured priority in your root switch. Just make sure that this new access switch has either higher priority configured or is left to default. Apart from this I do not see any possible STP issue.