How to Reduce the size of wtmpx file
Step 1: Introduction
The utmpx and wtmpx files are extended database files that have superseded the obsolete utmp and wtmp database files.
The utmpx database contains user access and accounting information for commands such as who(1), write(1), and login(1). The wtmpx database contains the history of user access and accounting information for the utmpx database.
Step 2: Create Backup of wtmpx
In order to create a backup of wtmpx first check the disk space in /tmp and then copy the file in /tmp directory
# /usr/lib/acct/fwtmp < /var/adm/wtmpx > /tmp/wtmpx.orig
Step 3: Empty wtmpx file
To empty wtmpx file us the following command
# cat /dev/null > /var/adm/wtmpx
Step 4: Zip original wtmpx file
Create a zip of original wtmpx file using gzip command
# gzip /tmp/wtmpx.orig
Step 5: Copy original wtmpx
Copy original wtmpx file in /var/adm/ for audit purpose
# cp /tmp/wtmpx.orig.gz /var/adm/