could not load library “$libdir/repmgr_funcs”: ERROR: could not access file “$libdir/repmgr_funcs”: No such file or directory

Question

I am planning to move data from postgres 9.3 to 9.6, in 9.3 its has repmgr 3.0.1 configured. tried to do pg_upgrade from 9.3 to 9.6 with out repmgr configured in 9.6, thrown error as

could not load library "$libdir/repmgr_funcs": ERROR: could not access file "$libdir/repmgr_funcs": No such file or directory

I tried to configure repmgr 3.0.1 on postgres 9.6. But doing so pg_upgrade failed, which states error at starting postgres 9.6

FATAL: could not load library "/usr/local/pgsql-9.6/lib/repmgr_funcs.so": /usr/local/pgsql-9.6/lib/repmgr_funcs.so: undefined symbol: RequestAddinLWLocks LOG: database system is shut down

Answer 1

PG 9.6.0 release notes says:

The RequestAddinLWLocks() function is removed, and replaced by RequestNamedLWLockTranche(). This allows better identification of custom LWLocks, and is less error-prone.

Due to this incompatibility with PG you cannot use the repmgr version that worked on PG 9.3 with PG 9.6.

You need to upgrade to a more recent repmgr version and because repgmr 3 is no more supported you should use repgmgr 4.