changing IP:
all depends on you current setting and new setting....
1- is the first SME connected directly to the modem ? we have SonicWall, that 1st SME is connected to for our VPN
2- is the modem acting as transparent gateway or acting as router... it is a Gateway transparent
3- static IP or dynamic? all static IP
4- cable, DSL... cable but moving into fiber connection with our new provider
5- type of connection : static, dhcp, mac address, pppoe... all connection via Static
6- what about the 2nd SME: behind first one, behind another connexion, then same question 1 to 5 for the second SME. for the second one is the same as the first. the same behind the SOnicwall/GW
new settings:
- same one with same provider ? should be the same but different provider totally.
- different ?
VPN and regenerate config:
- depends if a domain was used in it or IP, most probably it is an IP so yes. IP it is
also what version of SME are you using SM9? if yes time to upgrade.... Using now SME9.2 we will upgrade for sure, just want the site up and running with less down time.
If SME( also your certificates for VPN might about to expire (about 10 years) then as you are about to contact all your vpn user and update their config, you might want to do it once for the next 10 years....
you might get some of the information from the server-manager in check configuration and other from your ISP (current and future)