configuring cm list/tftp timeout

Unanswered Question
Jul 26th, 2010
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I have a UC540 + 2 x 7937 phones with almost default config. I removed the firewall part from the UC540, the rest is at default.

If i connect the phones to the internal switch ports, they work well.... i can make internal calls.

I configured an ip address on the fe 0/0 of the UC540 with ip address

I installed IP Comm on my laptop and cofigured it with tftp

I can call the the two7937 phones, everything is working.

I take one 7937 and disable dhcp, configure an ip address from the subnet,and the tftp server

When the phone boots it stays a long time in configuring CM list then tftp timeout.

From the phone i can ping the UC540 and from the UC540 the phone.

What is the problem here?

Thank you,


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EU UC Support Thu, 10/21/2010 - 06:00
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I have the same issue with my Wireless 7925 phones.....Did you find out what was wrong?



laposilaszlo Thu, 10/21/2010 - 06:13
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There is an ip tftp-server source address option on the UC!

By default this is the internal/lan address of the UC.

The UC will reply whit this address to tftp request and the external phones do not

know about this subnet/ip address!

Change the ip tftp-server source to the external address of the UC


make sure the external phones can reach the tftp-source address.

thank you,



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