Randomly Dropped calls on E1 with TE121/TE122


I have a problem with randomly dropped incoming calls on E1 FRA circuit. It happens roughly twice a day with no obvious reason. E1 is used only for inbound and calls can be dropped after 1,5 or 15 minutes, no regularity at all. I have 5 new installation 3 x TE121 + HWEC running HP ML110G7 and 2 x T122 + HWEC running ML110G6 - all with the same issue. I tested installs with and without hp raid driver to avoid IRQ problems. All installs are new and connected to the same TELCO with different locations.

In two cases I got kernel panic as well.


[quote]; [span_1]

cat /proc/interrupts



Please advise as we are running out of time. We bought Digium cards in a good faith but it actually works against us at the moment.


Hi, If you haven’t already, your best course of action is to contact Digium’s Technical Support Department. Digium does not provide any official support through these forums since it’s not an efficient way to track cases.

That being said, there isn’t enough information in your post to provide much help (which is another reason to open the support case since a support technicians can work with you to collect the required information necessary to troubleshoot your installation).

Some things I could recommend based on the information you provided:

A) If the kernel panics were only on the platforms with the TE122 (PCI express cards) I would first try to rule out that whether Active State Power Management is causing you problems. There was an open issue for this at issues.asterisk.org/jira/browse/DAHLIN-283 along with some background information about how the Linux Kernel works around issues with some BIOSes.

B) Try to determine why the calls are hanging up. Is your local Asterisk box hanging up the calls? Is the remote side disconnecting because of some problems that are detected?

C) Verify in your installation that all your cards are configured to recover timing from your provider.

D) Your configs look a little strange. It’s as if you had them originally set to use a channel bank, and then overridden those settings in the from-pstn context to use an ISDN link.

E) You can run a loopback test on your machines by following the instructions on How do I run a pattern loopback test on a Digium E1/T1 card?.

But I strongly recommend you open a support case if you haven’t already for the quickest resolution to your installation issues.


What does the log files say when you get a drop ?

grep the file for the workds red or yellow or hdlc and see if it show s up

I would set busydetect to no you dont need to detect busy tone and it can case hangups.