Manic supplied a quick command to manage the AIX wtmp file should it get too big for the system to handle.
Typically a last command will fail if the file is over 2Gb in size.
First convert the file to ASCII redirecting the output to a filesystem with enough space.
usr/lib/acct/fwtmp < /var/adm/wtmp > /tmp/wtmp.ascii.20110128 |
Now we compress it and clear out the original wtmp file.
compress /tmp/wtmp.ascii.20110128 >/var/adm/wtmp |
If, however, you wish to just prune the file, in SunOS (for example) you can do…
/usr/lib/acct/fwtmp < /var/adm/wtmpx > /tmp/wtmpx.orig tail -20000 /tmp/wtmpx.orig > /tmp/wtmpx.new /usr/sbin/acct/fwtmp -ic < /tmp/wtmpx.new > /var/adm/wtmpx rm /tmp/wtmpx.orig /tmp/wmtpx.new |
A similar approach can be used in AIX.
