I want to setup SER to forward calls to two or more asterisk SIP servers, having the asterisk servers control authorization etc. Is this
SER can forward calls to Asterisk. I did not understand the "asterisk servers control authorization" part. You mean authorizing INVITEs? Does Asterisk support that? I think no. It will accept your call and create another INVITE and send to the destination. If you meant registration, you can either register clients with SER or Asterisk. If you register with Asterisk, then there is no need for call forwarding using SER. (I know, your Asterisk knowledge is better than mine :-)
Asterisk does indeed support INVITE auth. I want all REGISTERs to go to the asterisk box(es) but I want to allow one of them to die. All data about the register is stored in a common database between the asterisk boxes, so it's no problem sharing that.
possible? Also, is it possible to have SER detect if one of the asterisk servers fail, and if failed, use the other one? This would leave me with only the SER box vulnerable alone.
Yes. This is possible. You can have failure routing in your script and check for the status of replies and then decide on what to do. Maybe like forwarding calls to another Asterisk or send to a voicemail server etc.
probably something like that, or just 'try forward to server A, didn't work, try server B, etc' btw, is it possible to schedule this via random or round robin somehow?
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