What is the maximum number of vlans does a switch supports?

[shoaib.hbd]

During an interview,

The interviewer asked me, " What is the maximum number of vlans does a switch supports "

I said " A switch supports 1001 vlans and in extended vtp mode it supports upto 4000"

then he asked " What if I have 5000 users in lan and I want to assign a vlan to each individual user then what would you do ?"

What would be the best answer or solution for that?

Thanks!!!

[Julio E. Moisa · Accepted solution]

Hi,

it depends of the kind of device platform, for example a 2960 could support less amount of VLANs than a Catalyst 9000.

From my point of view could not have a reason to assign 1 VLAN to 1 user at a company unless you are an ISP and you are using 1 VLAN for each client over a L2VPN.

If you want many many VLANs you also take in consideration the STP instances. 

[Leo Laohoo]

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@shoaib.hbd wrote:

I said " A switch supports 1001 vlans and in extended vtp mode it supports upto 4000" 

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More like around 3000 VLANs because there are VLANs that you can't assign and it's in a big chunk.

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@shoaib.hbd wrote:

What if I have 5000 users in lan and I want to assign a vlan to each individual user then what would you do ?" 

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What would I do?  I'd laugh at the interviewer and tell him that they need to hire someone who knows how to network.  Managing >1,000 VLANs is already a sign of a poorly designed network.