- Fixes GH #3178. Sets TCP connection id for keepalive based on the value in the database If unset, tcpconn_id will remain 0 and keepalives will work the same as they do today - Update documentation to clarify when it will use received vs AOR for keepalive

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#### Type Of Change - [ ] Small bug fix (non-breaking change which fixes an issue) - [ ] New feature (non-breaking change which adds new functionality) - [X] Breaking change (fix or feature that would change existing functionality)

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#### Description <!-- Describe your changes in detail -->

Updated usrloc module to re-use an active TCP session (if it exists). I marked this breaking only because the current code will use a UDP OPTIONS keepalive method even if the device is registered over TCP. I doubt that's what anyone would be expecting so I think the change is ok.

You can view, comment on, or merge this pull request online at:

https://github.com/kamailio/kamailio/pull/3219

-- Commit Summary --

* usrloc: re-use TCP connections for keepalive

-- File Changes --

M src/modules/usrloc/dlist.c (4) M src/modules/usrloc/doc/usrloc_admin.xml (9) M src/modules/usrloc/ul_keepalive.c (4)

-- Patch Links --

https://github.com/kamailio/kamailio/pull/3219.patch https://github.com/kamailio/kamailio/pull/3219.diff