I ran into this issue the other day while compiling Kamailio from source:

Jul 03 23:49:35 kamailio[305199]: ERROR: <core> [core/sr_module.c:608]: ksr_load_module(): could not open module </usr/local/lib64/kamailio/modules/ndb_redis.so>: /usr/local/lib64/kamailio/modules/ndb_redis.so: undefined symbol: redisvCommand
Jul 03 23:49:35 kamailio[305199]: CRITICAL: <core> [core/cfg.y:4024]: yyerror_at(): parse error in config file /etc/kamailio/kamailio.cfg, line 487, column 12-22: failed to load module

So what was going on?

Kamailio’s NDB Redis module relies on libhiredis which was installed, but the path it installs to wasn’t in the LD_LIBRARY_PATH environment variable.

So I added /usr/lib/x86_64-linux-gnu to LD_LIBRARY_PATH, recompiled and presto, the error is gone!

export LD_LIBRARY_PATH=/usr/lib/x86_64-linux-gnu:$LD_LIBRARY_PATH