WiFi VLAN run out of IPs

[techy32]

Hello,

 

We have few VLAN on our network which are working fine. Our WiFi VLAN run out of IPs and now we have changed the lease to one day. What possibilities do we have to increase IPs on WiFi VLAN?

[psydii]

Maybe.

What is the network address and mask?

[ChrisH]

Extend the subnet mask or if contiguous IP addressing is not available on the range you are using you will need to change to a different range.

[techy32]

We have no IP address available on this range. 172.16.0.53/24 is our IP range ( only 254 IP available ) but next range starts at 172.16.0.54/24..... and so on....

[ChrisH]

Can you use 172.16.55.0 as well? If so make your new range to use 172.16.54.0/23.

 

Edit: Address corrected.

Edited April 28, 2016 by ChrisH

[psydii]

I take it you mean 172.16.55.0/24 and 172.16.56.0/24?

 

In which case you can't extend the subnet.

 

 

 

 

You are going to have to create a new vlan, subnet and dhcp scope, and then configure the wireless controller (or the Radius Server) to put the clients into that. There will be interruption to service when you make this move. I recommend, since you already have reduced the lease time to 1 day, that the day before you are ready to cut over to the new VLAN/Subnet you configure the lease time to be very short (say 15 minutes) so that there is minimal disruption for clients. (there is a risk that if the existing subnet is highly over subscribed, and with a lease of 15 minutes you may end up with clients knocking each other off the wireless - I'd recommend scheduling the cut over for a well advertised maintenance window so that you don't get additional complaints during the cut-over period0

 

Pick a network address higher than the current highest in use, and as ChrisH says use a mask of 23 or even 22 for your new range.

 

You may need to update your ACLs in the Core Switch or Wireless controller too.

[techy32]

This is the only solution we have ....

 

Thanks psydii

[enjay]

You say you've got 254 addresses available - how many do you think you'll need?

 

How long will each device be connected for? Could you reduce the 1 day lease even further, perhaps to one hour?

 

Or look at a new subnet and DHCP scope, as per psydii's post. Our BYOD VLAN covers several thousand addresses.

[CyberNerd]

Create a subnet for each yeargroup :-)

RADIUS should automatically put the users into the correct vlan.

[ChrisH]

I take it you mean 172.16.55.0/24 and 172.16.56.0/24?

 

In which case you can't extend the subnet.

 

Nearly I meant 172.16.54.0 and 172.16.55.0 as the 54 was the next available (172.16.54.0/23).

 

And because as you said:

 

Pick a network address higher than the current highest in use, and as ChrisH says use a mask of 23 or even 22 for your new range.

 

You may need to update your ACLs in the Core Switch or Wireless controller too.

Edited April 28, 2016 by ChrisH