Migrating subnet

[9axqe]

A long time ago, I set up my home network to use 192.168.1.1/24. It worked well for many years, but I now find myself spending a lot of time connected over VPN to my network and recently, I have to do it from networks using the same exact subnet, which is conflicting.

Hence, I decided I needed to move to a less common subnet (for example, 192.168.46.1/24). The likeliness of me having to connect over VPN from a network using this new subnet should be quite low.

I am trying to build a bullet list of task for the migration and would appreciate feedback.


• connect to opnsense over IPv6
• edit firewall rules to allow 192.168.46.0/24 the same as 192.168.1.0/24
• change subnet mask of LAN intf from 192.168.1.1/24 to 192.168.1.1/16
• Change ISC DHCPv4 IP range to 192.168.46.200-240
• Move static DHCP assignments to 192.168.46.10-50 range (~ 30 static assignments)
• edit corresponding local DNS entries
  
  ** IPv4 IMPACT START **
• Powercycle individual devices to force them to acquire their new DHCP IPv4
• change DNS Server in DHCP settings to 192.168.46.1
• change IP of LAN intf to 192.168.46.1/16
• Edit AdGuard Home yaml config
  * remove bind to 192.168.1.1 and add bind to 192.168.46.1 (check if AdGuard cannot simply bind to 0.0.0.0)
  * reload adguard home
  
  ** IPv4 IMPACT END **
  
• change subnet of LAN intf to 192.168.46.1/24
• edit wireguard config (allowed IPs)



Any feedback or suggestion welcome.

[dseven]

Not sure that monkeying around with the netmask is going to make your life better. When you do step 9, your hosts will all lose internet, as they'll still be trying to use 192.168.1.1 as their default gateway. I'd probably just take the outage and reboot things as needed once after all the changes are in place.