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Re: Isolated Vlan Question

Hi,

My question is if its an isolated vlan (a vlan that is not routed), can I use any IP's inside the vlan.

Example, if the vlan is Vlan23 and I have put machines in there with IP addres (10.0.0.1/24, 172.16.31.6/24, 192.168.10.1/24),

there should be able to talk to each right ? since its a pure L2 environment.

I believe it should work but I do not have a lab to test this.

Thank you,

Cheers,

-SN-

1 ACCEPTED SOLUTION

Accepted Solutions

Re: Isolated Vlan Question

Hi,

An IP from a subnet A will not talk to an IP on subnet B, because to allow communication between different IP subnets you require a router (or routing device).

If on the same Layer 2 segment you have devices with different IPs (from different IP subnets), they won't talk to each other.

If you have a Layer two segment and you have a device with the IP 10.1.1.1/24, it will only be able to communicate with other devices on the 10.1.1.0/24

If you have a directly connected device on  the same Layer 2 segment with an IP from 192.168.1.1/24, they won't communicate, because the first IP packet between the devices need to be routed (there's no routing concept in a single Layer 2 segment).

Federico.

2 REPLIES

Re: Isolated Vlan Question

Hi,

An IP from a subnet A will not talk to an IP on subnet B, because to allow communication between different IP subnets you require a router (or routing device).

If on the same Layer 2 segment you have devices with different IPs (from different IP subnets), they won't talk to each other.

If you have a Layer two segment and you have a device with the IP 10.1.1.1/24, it will only be able to communicate with other devices on the 10.1.1.0/24

If you have a directly connected device on  the same Layer 2 segment with an IP from 192.168.1.1/24, they won't communicate, because the first IP packet between the devices need to be routed (there's no routing concept in a single Layer 2 segment).

Federico.

New Member

Re: Isolated Vlan Question

Hi Federico,

Yes agreed. Its a very simple question but never had to think of this till a server guy said that it can be any IP in the 'isolated vlan'. The catch here is that all the IPs has to be within the same subnet mask as you have mentioned below.

Thanks mate,

Cheers,

-SN-

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