Dear fellows,
I have Centos 5.4 linux with DNS server, all logs are normal, in my /var/log/ btmp files is getting larger day by day.
What is this btmp file for?
How can i reduce the file siez or control file size.
Waiting.
MAZ
It's the log file for bad login attempts (see man man lastb (Linux)). If it's growing fast you either have a really dumb user somewhere, or a forgotten script trying old credentials, or someone is trying to own your box. You can have it auto-cleaned using logrotate, or (if you don't need the history) truncate it using
: > /var/log/btmp