If use cvmfs_config wipecache to clear a previous mount, and then automount again a repository such as /cvmfs/oasis.opensciencegrid.org, I found I was not able to do cvmfs_talk -i cvmfs-config.cern.ch which was also automounted. It said
Seems like CernVM-FS is not running in /local/cvmfs/shared (not found: /local/cvmfs/shared/cvmfs_io.cvmfs-config.cern.ch)
and indeed the file was not there (I have CVMFS_CACHE_BASE=/local/cvmfs).
I enabled CVMFS_DEBUGLOG on cvmfs-config.cern.ch and the relevant line is:
(talk) socket created at ./cvmfs_io.cvmfs-config.cern.ch (fd 7) [02-10-2015 14:44:45 CST]
which looks like it worked. Both it and the original repo I was mounting use the same shared cache directory ...
Oh, I see two separate pairs of _cachemgr__ cvmfs2 processes. cvmfs_config wipecache doesn't actually unmount /cvmfs/cvmfs-config.cern.ch even though it says "Unmounting /cvmfs/cvmfs-config.cern.ch: OK" and everything in the shared directory (including the socket of course) is removed. That's why the socket is gone. The next time I automount a repo, it continues to use the previously running cache manager for cvmfs-config.cern.ch even though its cache was deleted and a separate cache manager is started for the repo sharing the same path. Not good.
Can you reproduce?