Currently we have the db2diag.log file going to the /home/instance/sqllib/db2dump path. Can we change that to another location, ie /var/???, so that it doesn't fill up the home filesystem? I believe you do it through updated the db cfg file but not sure. Any help would be great
Now you can see that DIAGPATH does not have a closing "/" as in your last question. So you can now set the new db2diag.log target filesystem to whatever you want. My one word of advice is not to use the /var filesystem. On AIX this is usually very very small and one of the first JFS filesystems to get extended by the SAs. Also "vi" and other utilties seem to like "/var/tmp" more so than "/tmp" in a base OS installation.
We have defined new volume groups and new file systems across multiple controllers and disks to limit DB2 I/O as mush as possible, even for db2diag which is infrequently updated depending on the setting. Depending on your setup, you might want to rethink "/var".