[asterisk-users] "Random" all circuits busy now message

[jan.sarin at securia.se]

Hi,

We have quite a large setup working just fine most of the time. We have
60 outgoing lines on PRI and we never use all of these lines. But
sometimes we get the "all circuits busy now" message, seemingly random.

Sometimes we get it before the call even goes through to PSTN. Sometimes
after 5 or 6 rings etc.

It seems that the carrier is signalling something and asterisk always
interprets this as "all circuits busy now" whilst a old-fashioned
exchange might say "busy" or "wrong number" or "hangup" etc.

What might cause asterisk to handle signals like this?

Thanks!

Regards,
Jan