DSL Modem Settings

My Qwest dsl modem went bad over the weekend. Purchased and installed new Actiontec PK5000 modem. All devices (DSL modem, pc’s, phones, CCTV, pos,) are now working and are accessable, except for my PBX which is using the latest version of Asterisk.

now I cannot access the PBX GUI. The new modem povisioned new IP address for my other equipment, but not for the PBX. When I run an angryip scan or try to ping the old pbx address (192.186.15.10 it cannot find it. I also run group scans 192.168.0.0 - 192.168.15.255 and no luck findind it.

Any suggestions please?