AIX GUIDE: Fix a /var Overflow

Check the following when the /var file system has become full:

You can use the find command to look for large files in the /var directory. For example:
```
find /var -xdev -size  +2048 -ls| sort -r  +6
```
For detailed information, see the command description for the find command.
Check for obsolete or leftover files in /var/tmp.
Check the size of the /var/adm/wtmp file, which logs all logins, rlogins and telnet sessions. The log will grow indefinitely unless system accounting is running. System accounting clears it out nightly. The /var/adm/wtmp file can be cleared out or edited to remove old and unwanted information. To clear it, use the following command:
```
cp /dev/null  /var/adm/wtmp
```
To edit the /var/adm/wtmp file, first copy the file temporarily with the following command:
```
/usr/sbin/acct/fwtmp < /var/adm/wtmp >/tmp/out
```
Edit the /tmp/out file to remove unwanted entries then replace the original file with the following command:
```
/usr/sbin/acct/fwtmp -ic < /tmp/out > /var/adm/wtmp
```
Clear the error log in the /var/adm/ras directory using the following procedure. The error log is never cleared unless it is manually cleared.
Note:

Never use the cp /dev/null command to clear the error log. A zero-length errlog file disables the error logging functions of the operating system and must be replaced from a backup.
1. Stop the error daemon using the following command:
```
/usr/lib/errstop
```
2. Remove or move to a different filesystem the error log file by using one of the following commands:
```
rm /var/adm/ras/errlog
```
  or
```
mv /var/adm/ras/errlog filename
```
  Where filename is the name of the moved errlog file.
  
  Note:
  
  The historical error data is deleted if you remove the error log file.
3. Restart the error daemon using the following command:
```
/usr/lib/errdemon
```
Note:
Consider limiting the errlog by running the following entries in cron:
```
0 11 * * * /usr/bin/errclear -d S,O 30   
0 12 * * * /usr/bin/errclear -d H 90
```
Check whether the trcfile file in this directory is large. If it is large and a trace is not currently being run, you can remove the file using the following command:
```
rm /var/adm/ras/trcfile
```
If your dump device is set to hd6 (which is the default), there might be a number of vmcore* files in the /var/adm/ras directory. If their file dates are old or you do not want to retain them, you can remove them with the rm command.
Check the /var/spool directory, which contains the queueing subsystem files. Clear the queueing subsystem using the following commands:
```
stopsrc -s qdaemon
rm /var/spool/lpd/qdir/*
rm /var/spool/lpd/stat/*
rm /var/spool/qdaemon/*
startsrc -s qdaemon
```
Check the /var/adm/acct directory, which contains accounting records. If accounting is running, this directory may contain several large files. Information on how to manage these files is in System Accounting.
Check the /var/preserve directory for terminated vi sessions. Generally, it is safe to remove these files. If a user wants to recover a session, you can use the vi -r command to list all recoverable sessions. To recover a specific session, usevi -r filename.
Modify the /var/adm/sulog file, which records the number of attempted uses of the susu command. Modify the /var/tmp/snmpd.log, which records events from the snmpdsnmpd daemon. command and whether each was successful. This is a flat file and can be viewed and modified with a favorite editor. If it is removed, it will be recreated by the next attempted daemon. If the file is removed it will be recreated by the
Note:

The size of the /var/tmp/snmpd.log file can be limited so that it does not grow indefinitely. Edit the /etc/snmpd.conf file to change the number (in bytes) in the appropriate section for size.

AIX GUIDE

Fix a /var Overflow

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