I noticed in recent versions of Ubuntu you get some system stats in a banner message when you connect using SSH. I thought this was pretty useful so have implemented my own version on our Red Hat servers at work.
This runs every 5 minutes as a cron job and updates the file /etc/motd (Message Of The Day) which is shown when a user logs in. Our servers already have a 5 line banner message with information including the server name and purpose of the server, hence the first 5 lines being saved and readded into a new /etc/motd each time.
#!/bin/bash
cat /etc/motd | head -n 5 > /tmp/file && cat /tmp/file > /etc/motd
CPUTIME=$(ps -eo pcpu | awk 'NR>1' | awk '{tot=tot+$1} END {print tot}')
CPUCORES=$(cat /proc/cpuinfo | grep -c processor)
echo "System summary (collected `date`)
- CPU Usage (total average) = `echo $CPUTIME / $CPUCORES | bc`%
- Memory free (real) = `free -m | head -n 2 | tail -n 1 | awk {'print $4'}` Mb
- Memory free (cache) = `free -m | head -n 3 | tail -n 1 | awk {'print $3'}` Mb
- Swap in use = `free -m | tail -n 1 | awk {'print $3'}` Mb
" >> /etc/motd
Now when we log in we get a summary like this:
