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About the ClearCase cache directory

Technote (FAQ)


Why are files created in the IBM® Rational® ClearCase® cache directory, ClearCase_check, and is it safe to remove them?


The cache directories are located as follows:

UNIX® and Linux®:

Microsoft® Windows®
C:\Program Files\Rational\ClearCase\var\cache

ClearCase_check cache

Location on Windows:

C:\Program Files\Rational\ClearCase\var\cache\ClearCase_check

Location on UNIX/Linux:


Note: The MultiSite_check directory will not appear on systems that do not have or use MultiSite.

These directories contain several zero-length files:



[ClearCase_check]$ ls -al
total 8
drwxrwxrwx  2 vobadm    vobadm    4096 Oct 20  2005 .
drwxrwxrwx  4 root      root      4096 Mar  9 17:07 ..
-rwx------  1 cmoir     cmoir        0 Feb  9 22:02 cmoir
-rwx------  1 testuser  testuser     0 May 11  2006 testuser
-rwx------  1 1000      502          0 Sep  9  2005 testuser2
-rwx------  1 vobadm    vobadm       0 Dec 19 15:55 vobadm


C:\Program Files\Rational\ClearCase\var\cache\ClearCase_check>dir /d
 Volume in drive C has no label.
 Volume Serial Number is 8017-F8A8

 Directory of C:\Program Files\Rational\ClearCase\var\cache\ClearCase_check

[.]              [..]             clearcase_albd
               1 File(s)              0 bytes
               2 Dir(s)  36,241,784,832 bytes free

These files are created by user access to a ClearCase server.
They could have also been left behind from a previous version of ClearCase that was installed on the machine and not removed properly.

Note: On UNIX/Linux, the user creates ClearCase processes, where on Windows, the clearcase_albd is the only account managing processes. This is why there are user accounts on UNIX/Linux and only the clearcase_albd account on Windows.

The cached information relates to the UID/SID of the user and GID/SID of the group accessing ClearCase on the host so that credential look-up is improved.


Entries without a name associated to UID or GID, such as testuser2 above, may be a source of security concern in some companies. Can these files be removed?

Older or incorrect entries can be safely removed, especially the ones with bad UID/GIDs, as they likely do not represent current users of the system. Once removed, ClearCase will recreate the entry if necessary.

Note: It is recommended not to remove any files that have a recent timestamp.

CCshmemV3 cache files (Windows only)

Another file stored in the cache directory is the CCshmemV3 cache files.
These files are cached credentials data from users that have logged into the system.

The files with the appended Windows SID can be safely removed as well as these will add up to be a significant amount of space if many different users are logging into a system.

( CCshmemV3.S-1-5-21-141845252-1443263951-584457872-1365)

Note: If deleting one of these files results in an "Access is denied" error message, the message indicates ClearCase is still using the file you are trying to delete.

Related information

clearmake: Error: Unable to create a container in VOB
About the temporary files created by ClearCase

Document information

More support for: Rational ClearCase

Software version: 7.0, 2002.05.00, 2003.06.00

Operating system(s): AIX, HP-UX, IRIX, Linux, Solaris, Windows

Reference #: 1257887

Modified date: 13 April 2007