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New Member

where does phone get ip address on a cme

Im trying to figure out where the ip phone gets its ip address from in an CME environment, and what the process is. Can someone shed some light on this for me please?

  • IP Telephony

Re: where does phone get ip address on a cme


did u configure DHCP server on the same CME router, if u did at startup ip phone will broadcast to discover if there is a dhcp server, once there is a dhcp server discovered, dhcp will reply with an ip address, subnet mask and default gateway, DNS (assuming all are configured under ip dhcp pool..on the router)

in addition if option 150 is configured under ip dhcp pool, dhcp server will include the tftp ip address in its response, assuming u have also already configured this...

once the ip phone gets the tftp address it will contact this tftp to pull its config files, after the process completes it will reset (if first time) and register with CME, then everytime ip phone reboots it will also contact tftp to verify its config file or if there is a new one (with updated config) ..

u can also have a dhcp server on any server (HW) for example u may have Win dhcp server being configured for voice and/or data vlans scopes to give ip phones and also if needed PCs their ip addresses..


please remember to rate helpful posts


New Member

Re: where does phone get ip address on a cme

so where does the .cnf and .xml files come into play?

Hall of Fame Super Gold

Re: where does phone get ip address on a cme

CME creates dinamically the .cnf and xml files. To see them, do "show telephony-service tftp-bindings" and "more ".

Hope this helps, please rate post if it does!

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