Fix /var/adm/wtmp: Value too large to be stored in data type.

Today morning while I checked who last loged on my dbserver I saw strange error.

bash-3.00# last
/var/adm/wtmp: Value too large to be stored in data type.

My OS is AiX

bash-3.00# uname -a
AIX ?????? 1 6 00F6A54E4C00

Check size of file:

-bash-3.00$ ls -lrt /var/adm/wtmp
-rw-rw-r--    1 adm      adm      2148154327 Feb 05 08:47 /var/adm/wtmp
-bash-3.00$

It is around 2GB.

For next analyze copy file to your backup location

bash-3.00# cp /var/adm/wtmp /u01/BackUpFiles/

Now you may reset file.

bash-3.00# cat </dev/null >/var/adm/wtmp

Check again the last command

-bash-3.00$ last
oracle    pts/1        xx.xx.xx.xx            Feb 05 09:13   still logged in.

wtmp begins     Feb 05 09:09


If you want to see the last 10 failed logins.

bash-3.00#  who /etc/security/failedlogin | tail -10
oracle      ssh         Dec 27 17:10     (xx.xx.xx.xx)
oracle      ssh         Dec 31 13:54     (xx.xx.xx.xx)
UNKNOWN_    ssh         Jan 08 14:12     (xx.xx.xx.xx)
UNKNOWN_    ssh         Jan 14 13:12     (xx.xx.xx.xx)
UNKNOWN_    ssh         Jan 14 13:12     (xx.xx.xx.xx)
UNKNOWN_    ssh         Jan 22 15:29     (xx.xx.xx.xx)
UNKNOWN_    ssh         Jan 24 12:26     (xx.xx.xx.xx)
UNKNOWN_    ssh         Jan 24 12:26     (xx.xx.xx.xx)
UNKNOWN_    ssh         Jan 24 12:26     (xx.xx.xx.xx)
oracle      ssh         Feb 03 17:09     (xx.xx.xx.xx)
bash-3.00#


P.S: you have to login as root to execute those commands.