vlan naming

[bluesea2010]

Hi,

I  have layer 3 at access layer ,

In each access switch there is vlan for voice . 

for example  sw1 vlan 10 ,10.0.1.0/24 

sw2 vlan10 10.0.2.0/24

What is the best practice for the  creating vlan id , I mean do I need to keep different vlan ID or same ID in switch 

Thanks

[MHM Cisco World]

if there L2 trunk/access link between SW then sure you must use same vlan-id

if there is no L2 link   then you can use different.

[Karsten Iwen]

I would prefer to have the same VLAN ID and name on each switch. This way it will be much easier for a human.

The switch itself will not care at all. And with the possibility to send VLAN names instead of IDs in your RADIUS Access-Accept for AAA using different IDs but same name per function will also work. Only if you have different IDs *and* names per access-layer switch, this should be an operational nightmare.

[bluesea2010]

Hi @Karsten Iwen @Leo Laohoo 

You mean for assigning vlan  dynamically from cisco ise 

Thanks

[Leo Laohoo]

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@bluesea2010 wrote:
You mean for assigning vlan  dynamically from cisco ise 

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Yes.

[Karsten Iwen]

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You mean for assigning vlan  dynamically from cisco ise 

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Or any RADIUS server of your choice. Ok, preferably the ISE, but any other would also be ok.

[Kasun Bandara]

I assume you have connected all access switches together via distribution switch or core switch. or can be connected all access switches. if so better use same VLAN ID and name to send traffic between switches and maintain in same VLAN.

[Joseph W. Doherty]

Unsure there's a generic "best practice", but I would suggest keeping all VLAN IDs, unique, if possible.  This to avoid the situation, and possible confusion, whether two, for example, VLAN 10s, on two different switches, are really the same L2 broadcast domain VLAN, or they just happen to be used for the same purpose, e.g., voice VLANs.

In the case where different VLANs are NOT the same L2 broadcast domain VLAN, but are used for the same purposes, you can, at least on most (all?) Cisco switch attach a functional purpose VLAN name.

Also, you might VLAN numbering like, first two digits, VLAN "instance", second two digits, VLAN "purpose".

e.g.

1st instance of voice VLAN, 110.

2st instance of voice VLAN, 210.

4th instance of data VLAN, 420.

etc.

On large chassis switches, might have more than one VLAN of same kind.

E.g. 8th instance, voice VLANs, 1 and 2, same device, 810, 811.

Basically, figure you have, usually always 3 digits, in a VLAN ID, which you can dedicate for some meaning.  You can also get into 4 digits, but the 4th digit doesn't support 1..9, and other restrictions, with Cisco, working in the extended VLAN numbering range.

[Leo Laohoo]

I would recommend using the same VLAN number and the same VLAN name (case sensitive).  This is very beneficial if someone is going to implement Dot1X with VLAN name.

Importantly, turn VTP off!