Addressing Vlans and DHCP

JED2021
Getting noticed

Addressing Vlans and DHCP

I have a Vlan1 with address 172.16.12.0/23

 

DHCP is enable for this subnet

 

I  am running  low but not dangerously low on free addresses

 

To grow the DHCP is it just a matter of  changin the addressing and vlans  

From

172.16.12.0/23

To

172.16.12.0/22.

 

Is there any impact on the users since now the Subnet MASK has changed?

4 Replies 4
alemabrahao
Kind of a big deal
Kind of a big deal

It depends, you just have to ensure that there is no overlapping with another network and you have to be careful if you have a specific route for that network or firewall rule. Other than that, it's alright.

I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.

Please, if this post was useful, leave your kudos and mark it as solved.

no overlap,

no rules.

 

I was curious if Meraki has a show route command.

 

I look at the routing table but it does not take into account supernets

Brash
Kind of a big deal
Kind of a big deal

Other than what's mentioned above, you may also encounter issues with the devices communicating with eachother.

Despite being in the same L2 domain, the computer's subnet mask will tell them that they're in different domains and will forward to their default gateway.

cmr
Kind of a big deal
Kind of a big deal

Following up on what @Brash said, you'd be best to reserve all the new addresses so that they don't initially get given out and only when everyone has renewed their IP (and you have fixed the subnet mask on anything with a static IP) would you allow the new part of the DHCP range to be given out.

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