Address Selection for New Networks

scottalanmiller

@Joel said in Thoughts on EdgeMax Pro 8:

Each office will have it's own subnet range:

192.168.1.1
192.168.2.1
192.168.3.1 and so forth.

I'm going to make a new thread for this as this is unrelated to the router selection. But...

Don't use /24. No reason whatsoever to limit like that. Use /23 and get 500+ devices for each customer. You won't be able to change this later without being a big pain because you are making address ranges next to each other.
Avoid the bottom two networks for general reasons. So no 192.168.0.0 and no 192.168.2.0. So make your ranges like this...

192.168.4.0/23
192.168.6.0/23
192.168.8.0/23

scottalanmiller

Tagging @Joel as this is actually his topic.

scottalanmiller

Also, networks are written with their network number, not a random host within the range. So if you are talking about the 192.168.0.0. - 192.168.0.255 network, its network name is 192.168.0.0. 192.168.0.1 is a specific host on the network, but 192.168.0.0 is the address of the network itself.

Francesco Provino

@scottalanmiller , why not use something like 10.X.Y.0/23 (or 22, for what matter) where X identify the company (I use the road number of the headquarter, as example) and Y identify the subnet inside the company? I use this subnetting principle so I never get identical subnet (no subnet superposition using VPN). Apart from DNS, I can usually guess a VM or device role just looking at the IP address.

scottalanmiller

@Francesco-Provino said in Address Selection for New Networks:

@scottalanmiller , why not use something like 10.X.Y.0/23 (or 22, for what matter) where X identify the company (I use the road number of the headquarter, as example) and Y identify the subnet inside the company? I use this subnetting principle so I never get identical subnet (no subnet superposition using VPN). Apart from DNS, I can usually guess a VM or device role just looking at the IP address.

He's only doing one subnet per company, and they all share one address. So he's covering these bases already, there is no overlap potential since they are all one network scheme from the beginning.

JaredBusch

Personal preference for me is to use a 10.X.X.0/24(23) schema.

For clients that I have full setup over, the 2nd octet is set per client. The 3rd octet is site.

Client 1:
10.254.0.0/23 = main office network
10.254.10.0/24 = branch office 1
10.254.20.0/24 = branch office 2
etc.

Client2:
10.253.0.0/23 = main office network
10.253.10.0/24 = branch office 1
10.253.20.0/24 = branch office 2
etc.

JaredBusch

@scottalanmiller said in Address Selection for New Networks:

Don't use /24. No reason whatsoever to limit like that. Use /23 and get 500+ devices for each customer. You won't be able to change this later without being a big pain because you are making address ranges next to each other.

I use a 23 for a main office, but almost all SMB that I see will not come close to filling up a /24 anyway.

If you properly setup everything as DHCP with reservations for the important things, you will only have a few key systems that need to be manually changed when you need to update your scope.

Granted it is easier if you think you will ever potentially need to expand in the near term to start with a /23.