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Re: OT - CallManager and NAT posted 11/29/2006
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Check your URLs configured in the call manager. do you have IP addresses in there instead of the dns name of the CCM? Im going to assume that since the phones are downloading the images already, the option 150 of your DHCP is set correctly. i'd bet the CCM is handing out a url of the inside address of itself to the phone. make sure the box you are using for dns resolution can resolve the callmanager based on the name and update the urls in ccm accordingly. give that a whack. (at least that's what I would look into next if you already havent)

Brad Ellis
CCIE#5796 (R&S / Security)
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----- Original Message ----- From: "Andi Bennett" <bigandibennett@xxxxxxxxx>
To: <ccielab@xxxxxxxxxxxxxx>
Sent: Wednesday, November 29, 2006 8:50 AM
Subject: OT - CallManager and NAT

Sorry for the off topic here but this has me a bit stumped.

I have Cisco IP
Phones on the "outside " of the network connecting to a CM on the "inside" of
the network.
Now, the phones can alternate TFTP to the CM, they then get an
image, but they the try and connect to the real addresses of the CM's, which
is obviously unroutable on the outside.

I have

ip nat outisde source static
configured to get the phones to the CM.  I think the problem is that the
return TFTP image has the embedded real addresses of the CM in it.

as a run
down of config I have

ip nat outside source static
(Publisher + TFTP server)
ip nat outside source static (CM1)
ip nat outside source static (CM2)
The phones get the image, then keep trying to connect tot he 10.18.192.x

I've looked at using the ip nat service port sccp command, but it
seems to have no effect as the phones still try to connect to the real CM
addresses, not my staic NAT entries.

Is what I'm trying to do possible, or am
I barking up the wrong tree??

Any advice would be appreciated.


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