Different masks in single vlan range

[jopetik09]

I have a vlan configured like below...

interface Vlan20
desc printers
ip address 10.23.86.1 255.255.252.0

interface Vlan22
description laptop

ip address 10.23.104.1 255.255.252.0

Now I have a pc configured IP: 10.23.87.108 Mask: 255.255.240.0 DG: 10.23.86.1
I have another pc configured IP: 10.23.89.20 255.255.252.0 DG: 10.23.86.1

Is the both above pc's will communicate with others and other vlan's?

Thanks in advance.

Jopeti

[Shashank Singh]

Hi Jopeti,

It does not look like the ip addresses of the PCs are in vlan 22 subnet. Please see the range of valid IP addreses in both vlans below:

Host Address Range for vlan 20

10.23.84.1 - 10.23.87.254

Host Address Range for vlan 22

10.23.104.1 - 10.23.107.254

Regards,

Shashank

p.s: please rate the helpful post

[jopetik09]

Hi,

Sorry type error in the IP rage.
below are the correct ones....

interface Vlan20
desc printers
ip address 10.13.96.1 255.255.252.0

interface Vlan22
description laptop
ip address 10.13.104.1 255.255.252.0

Now I have a pc configured IP: 10.13.96.108 Mask: 255.255.240.0 DG: 10.13.96.1
I have another pc configured IP: 10.13.99.20 255.255.252.0 DG: 10.13.96.1

Is the both above pc's will communicate with others and other vlan's?

Jopeti.

[Shashank Singh · Accepted solution]

Hi,

Following is the valid range for vlan 20 where your PCs seem to be connected (as the default gateway on PC is vlan20 SVI)

10.13.96.1 - 10.13.99.254

Both PC IP addresses fall in this range so they will be able to talk to each other. To communicate with other vlan, there needs to be intervlan routing configured on the switch or the switch should be layer 3 with IP routing enabled.

Cheers,

Shashank

P.S. Please rate the helpful post.

[Latchum Naidu · Accepted solution]

Hi Jopeti,

As log as the default gateway for both pc is same 10.13.96.1 they will ping with each other.

And the both IP's will fall under the Vlan 20 so they will be ping with each other.

Regarding communicate with other vlans you need to have a L3 (switch or router) to make intervlan routing. Hope you have it where you define those two vlan's 20 and 22.

Hope this clear you and please rate the helpfull posts.

Regards,

Naidu.

[jopetik09]

Hi All,

But the subnet mask is different for both pc's right?

will that not be a problem.

Jopeti

[Shashank Singh]

Hi Jopeti,

I do not think that is a problem.

Cheers,

Shashank

[jopetik09]

Hi,

Can you bit aloberate how it is not be a problem?

Jopeti.

[Shashank Singh]

Hi,

IP addresses of both the PCs are in same subnet. Please see below:

10.13.96.108 255.255.240.0 means 10.13.96.1 - 10.13.111.254

10.13.99.20 255.255.252.0 means 10.13.96.1 - 10.13.99.254

Why do you think there will be a problem?

Cheers!

Shashank

[jopetik09]

I got it but..

My concern is the subnet masks are different of both pcs.
As per vlan both pc's subnet masks should be 255.225.252.0

But for PC 10.13.96.108 it is 255.255.240.0

If i assign subnet mask for the above pc as 10.13.96.108  255.255.254.0

will that work?

Jopeti.

[bierrrr.CC]

It will work. It's as far as possible from the best practices but there should be no problem with connectivity. The communication itself might be inefficient as in some cases PCs will have to send packets to the gateway instead directly to the target computer.

[Latchum Naidu · Accepted solution]

Hi Jopeti,

Please don't concern about the masks bits.

As I told previously as long as the DG is same for whcih ever the pcs they will be communicate with each other.
You can assign different subnet mask to get more IP's or some other reason.

Please get things as per best practices....

Hope this clear you and please rate all the helpfull posts...

Regards,
Naidu.

[jopetik09]

Hi Naidu and Shashank Thanks for your inputs and time.

Jopeti.