DHCP Full

[ankitohc]

Hello

We are using a /24 Class C address. and we are full with IP addresses, how can we have more IP's?

We have DHCP server on windows 2012 server

[M02@rt37]

Hello @ankitohc,

configure an other /24 subnet ?

[ammahend]

few of the things you can do is, reduce lease time, so that addresses become available sooner if not used, change subnet to /23 or /22 based on your client count needs and future scale, assign a secondary IP on interface, configuring a secondary IP address can provide relief to the DHCP pool shortage without disrupting existing services.

[ankitohc]

assign a secondary IP on interface

Which interface are you talking about? What will happen to those hosts who have the subnet/24? Will that change?

We have meraki firewall>> connected to core switches>>>access switch

I don't want any downtime on productions

[ammahend]

where is the gateway for the host running out of IPs, on core or Meraki Firewall ? if core, what kind of Core device is this ?

[ankitohc]

Gateway is firewall -

[ankitohc]

Sorry we have /22 address, I want to tell you one thing, Which I just noticed

We are currently using this range -  

Network ID Host Range Broadcast
192.168.72.0 192.168.72.1 - 192.168.75.254 192.168.75.255

and 

that means we have not defined the complete range of subnets because here we will get 64 networks in /22 so we need to add more network on firewall so we can have more IP's right

[ammahend]

can you elaborate what you mean by this sentence ? "that means we have not defined the complete range of subnets because here we will get 64 networks in /22 so we need to add more network on firewall so we can have more IP's right"

Also from firewall just send screen shot of Security & SD-WAN>configure>Addressing & VLANs>Routing

[ankitohc]

What I am saying /22 We have configured the 192.168.72.0 network which means we did not configure the other networks which come under /22 

https://www.calculator.net/ip-subnet-calculator.html?cclass=any&csubnet=22&cip=192.168.72.0&ctype=ipv4&x=Calculate

[ammahend]

got it, to answer your previous question " add more network on firewall so we can have more IP's right"

Yes you can ad new subnet and associate it with a VLAN, you have to do other due diligence like configure ports in vlans, Nat for the new subnet, DHCP pool etc.

or you can change IP use 192.168.72.0/21, it will give you more room without adding new vlan, but you still will have to change DHCP Scope on DHCP server and MX interface etc. Will recommend to plan and make the changes after hours.

[ankitohc]

.Alright, Thank you for the detailed explanation- I will try to make the changes and see how it goes. 

[ankitohc]

Hello

Yes you can ad new subnet and associate it with a VLAN, you have to do other due diligence like configure ports in vlans, Nat for the new subnet, DHCP pool etc.

Can you please share the steps? what are the actions I need to take to make changes when I create new subnet.

So there will be a different default gateway for the new vlan, right?