WebSphere technical support has seen some subtle maintenance failures on UNIX system when the setting for the maximum number of file descriptors is set too low. When the Update Installer invokes <b>iscdeploy</b> to rebuild the administrative console application (isclite), the iscdeploy step can fail if the file descriptor limit is set too low. The maintenance will complete with no exceptions, but an attempt to log into the administrative console will fail with various types of errors. For example, in one case a customer's system defaulted to 1024 file descriptors (determined by issuing "ulimit -n") and iscdeploy failed during the application of a fix pack to Network Deployment. Later, the customer attempted to log onto the administrative console but errors began to appear within the initial administrative console frame as it was painted.

To avoid the problem altogether before you apply maintenance, dynamically set the number of file descriptors to a higher number compared to the default setting. For example, when logged onto the user ID that will run the Update Installer, issue "ulimit -n" to see the current file descriptor limit. Some systems default to 1024, which is considered too low. You can issue the command again with a value to temporarily override the default setting - for example "ulimit -n 8192". Alternatively, you can edit file /etc/security/limits.conf and define a soft and hard limit value for the user ID that starts WebSphere. Here is an example permanently increasing the ulimit value, assuming root is the user ID that starts WebSphere:

/etc/security/limits.conf

root soft nofile 8192
root hard nofile 32768

If you find that the administrative console application has a problem after applying maintenance, possibly due to a file descriptor limit that was set too low, you can manually rebuild the administrative console application by following these steps:
1. At a minimum, double your setting for the file descriptor limits
2. Stop all WebSphere processes
3. Navigate to <was_root>/profiles/<dmgr_profile_name>/bin
4. Issue iscdeploy.bat -restore | iscdeploy.sh -restore (This might run several minutes; warnings will be issued but no errors should occur)
5. Restart WebSphere