Common Problems while using CacheFS

This section lists the following common problems encountered with CacheFS and suggests ways to correct them.

“Cannot open lock file /c/.cfs_lock” “Cache /c is in use and cannot be modified” Message
“cachefsstat: Cannot zero statistics” Message
“cfsadmin: Cannot create lock file /test/mnt/c/.cfs_lock” Message
“Cannot open lock file /test/c/.cfs_lock” Message
“/test/c/.cfs_mnt_points is not a valid cache” Message
“mount failed No space left on device” Message

The error indicates that cache directory is in use. However, the actual reason for this error may be that the cache directory does not exist or "/c" may not be a cache directory.
Check if a directory named "/c" exists and if it is a cache directory. If not, delete the directory "/c" or use a different cache directory

Only a root user can zero-out the statistics. So the user who used this command was not a superuser. Login as the superuser to run this command.

Indicates that you do not have write permissions to the filesystem where cache directory is being created.

"c" may not be a valid cache directory. As fsck also has failed, the only way to recover from this problem is to delete the cache and recreate the cache directory using cfsadmin command.

Cache may not be clean, run fsck and try mount operation. (There could be a message in syslog that states "WARNING: cachefs: cache not clean. Run fsck")
CacheFS parameters (provided along with "-o" option to cfsadmin command) used to create the cache directory is very small. In this case, there would be a message in syslog that states "WARNING: CacheFS: not enough space to create <fscache directory name>".
To fix this problem, user has to increase the CacheFS parameters using "-u" option in cfsadmin command.

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