[CentOS] Subnet expansion

[John Doe]

From: Fajar Priyanto <fajarpri at arinet.org>

> Currently I have this network:
> 10.1.16.0/22.
> 10.1.16.0-10.16.17.254 are DHCP managed
> 10.1.18.0-10.1.19.254 are statically assigned
> If I need to expand it to:
> 10.1.16.0/20
> 1. What is the best way to do it with minimal network disruption?

I am no subneting pro but:
Currently you have half DHCP and half statics...
How will it be with the /20?  Still half/half?

  $ ipcalc -nb 10.1.16.0/20
  Address:   10.1.16.0            
  Netmask:   255.255.240.0 = 20   
  Wildcard:  0.0.15.255           
  =>
  Network:   10.1.16.0/20         
  HostMin:   10.1.16.1            
  HostMax:   10.1.31.254          
  Broadcast: 10.1.31.255          
  Hosts/Net: 4094

A /20 half/half would give:

  10.1.16.1-10.1.23.254
  10.1.24.1-10.1.31.254

> 2. If I keep some machine with 22 subnet mask, will it still be able
> to talk to the other machines in it's range?

They would talk to 10.1.16.1-10.1.19.254 ones, but would go for the gateway for 10.1.20.1-10.1.31.254

JD