What does , “rollover performed” , in a log mean?

Hi All,
Apologies for my lack of knowledge.

Could anyone tell me what, “rollover performed” means pease?
in a log file.

I was doing: cat /var/log/fail2ban.log

and saw this , “rollover performed” ?

Thanks in advance…

I think it’s pretty obvious:

INFO       rollover performed on /var/log/fail2ban.log

That means the log has been rotated, if you are familiar with the term log rotation. That means the old log file has either been deleted and a new one created, or the old log has been renamed to .log.date-at-the-time-of-rotation and a new one created. Rotated logs eventually get discarded if you don’t elect to back them up. Which is fine, since most logs are informative anyway, but the importance of logs is either to debug problems, or to make statistics.

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Thank you for taking the time to tell me what it meant .

I really appreciate your help… (now I know)

To add to biky’s explanation, try this and see what pops up for you.

$ ll /var/log/fail2*
-rw-r----- 1 root adm  12260 2022-08-14 10:02 /var/log/fail2ban.log
-rw-r----- 1 root adm 142425 2022-08-13 23:37 /var/log/fail2ban.log.1
-rw-r----- 1 root adm  18628 2022-08-06 23:42 /var/log/fail2ban.log.2.gz
-rw-r----- 1 root adm  22258 2022-07-30 22:16 /var/log/fail2ban.log.3.gz
-rw-r----- 1 root adm 413019 2022-07-23 23:47 /var/log/fail2ban.log.4.gz

Apparently my log rotation is four deep, with the most recently rolled-over one being uncompressed, then the three oldest ones being zipped to save space.

If you haven’t heard of it yet, zgrep will work on all of those files, so it’s easy to find stuff spanning all the logs, text or compressed.

$ zgrep rollover /var/log/fail2ban.log*
/var/log/fail2ban.log:2022-08-14 00:00:01,152 fail2ban.server         [959]: INFO    rollover performed on /var/log/fail2ban.log
/var/log/fail2ban.log.1:2022-08-07 00:00:01,666 fail2ban.server         [959]: INFO    rollover performed on /var/log/fail2ban.log
/var/log/fail2ban.log.2.gz:2022-07-31 00:00:02,608 fail2ban.server         [959]: INFO    rollover performed on /var/log/fail2ban.log
/var/log/fail2ban.log.3.gz:2022-07-24 00:00:02,424 fail2ban.server         [959]: INFO    rollover performed on /var/log/fail2ban.log
/var/log/fail2ban.log.4.gz:2022-07-17 00:00:01,893 fail2ban.server         [934]: INFO    rollover performed on /var/log/fail2ban.log

Hi Eric,
Thanks for the information.
I was not aware of zgrep, I’m new to linux .

I will give it ago… thanks again

lnav is a new Linux CLI tool that @lawrencesystems and @jay mentioned very briefly on the Home Lab show. I have just started using it, but it will automatically colorize and open your log files even the compressed ones. On Debian stable I just installed the version from the repos.

sudo apt install lnav

I’m using the tool to grow in my understanding of what logs can help me diagnose issues when they occur on my systems.


Who needs lnav and colored cat when you have lolcat?


Thanks for your reply,
I’ve made a note of lnav

I will have a look at it.

thanks again …

Wow, that is a colourful log.

Looking at the image of your log.

My eye was taken to the top right of the image, showing:

cpu temp

Days up

Not sure what 5.10.92_1 is ?

Linux penguin


vol= 100

That looks great (and useful)

I’m using Ubuntu 22.04.1 LTS, would I be able to install that block of information icons on my laptop?

If so, please let me know how to do that, it would be so good to see that information…

Not sure if you can. I am using sway and the bar on top is swaybar with a custom shell script. Since you are new to linux, I would not exactly recommend it. Maybe you can get into Openbox and another one of the status bars.

Each status has an emoji, they are just normal, bare basic emojis. The linux penguin and the number behind it is the linux kernel version I am running.

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Hi ,
thank for your reply,
Yes, I guess it will be above my skill set for now.
However thanks for taking the time to explain about the status bar.