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Debug fax relay T.30


I'm having some problems with inbound T.38 faxing on an AS5350. I'm working with Dialogic show is supporting their SR140 virtual fax card. I am turning on the fax relay debugging, but need to filter only the senders who are having fax failures to isolate the debug logs to those senders. Otherwise you can't tell which debug line goes with which fax session if when you have multiple faxes going through the gateway.

I'm using IOS 12.4(25c) Mainline

Problem is when I enter the debug command:

"debug fax relay t30 calling-number 2625551212"

It does turn on the debugging, but still does them for all senders as if I had entered "debug fax relay t30 all"

Any clues? Is this maybe a bug in this IOS version?

1 Reply 1

Daniele Giordano

Your command is right. This is mentioned  in Cisco manuals:
"When using the command debug fax relay t30 all-level-1 on voice gateways with many simultaneous fax relay calls occurring, the output can be confusing to read because all the fax messaging for all calls will be displayed together. In these situations, run the debug command for only the specific called or calling number that you are interested in with the commands debug fax relay t30 called-number or debug fax relay t30 calling-number."

Have you wrote the correct calling number?
Use "show call active voice compact" to check calling and called number.

You can use also Wireshark. It has a very usefull tool to analyze and debugging your problems.

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