How to tell how long last reboot took
 

Is there certain lines I could look through in a certain log file to give me a rough estimate of how long the last, or last couple, reboots of a server took?

I'd say check out /var/log/messages and see and look for the time you think it was rebooted and go from there

Linux command w will show you the details

or

cat /proc/uptime

^ I think he wants to know how long the actual reboot took.... Not how long the server has been up.

Correct, I want to know how long the server is down for while it reboots, on average, or at least the last time.

The problem is is that I dont know when the last time it was rebooted. Can i just grep for certain phrases, then subtract the time stamps to give me the time?

I just looked on the server, its been up for almost 100 days, but my messages files only go back to March, and that ones only 15k :-(

Can anyone think of another way to figure this out?

? does it not start deleting cache files after it fills up
may be why your log is short

hope this helps

yeah, it overwrites them as time goes by, not sure why they are so small though.

The settings for the num of logfiles preserved is in the logrotate configs

logrotate.conf
logrotate.d

is goood
 

is good

it looks like i'm keeping 4 files, but i dont know why these ones are so small.