I am using asterisk 11 based PBX (issabel). around 2000 extensions. While I am giving reload, sip reload, all extensions goes to unreachable. We cannot make calls during the reload. After reload the calls go normally.
What is the reason for that? How to avoid the hanging issue?
I think it is very unlikely that anyone here is going to be able to help with
this query.
Issabel is a large system based around Asterisk, but the Asterisk
developers here did not create the dialplans or any of the rest of the
infrastructure you are using
The chan_sip driver is deprecated and no longer supported.
Unless you can get some assistance from the Issabel developers, or at least
upgrade to a supported version of Asterisk, there may not be a helpful answer
to your problem.