Tools for monitoring performance and troubleshooting Ubuntu VPS web servers

• Munin – graphs of system resources over time. Very nice. Can be a bit difficult to setup.
• top – system stats
• iotop – like top, but for io stats. Install [bash]sudo apt-get install iotop[/bash] Useful setup [bash]iotop -b -o -d 30 -t[/bash] -b (batch – so you can keep a running tally of results) -o (only those processes with io) -d (delay and seconds – how often to print out stats) -t (include time in printout)
• vmstat – stats on memory, io, swap, cpu and system. Example: [bash]vmstat 10[/bash] (prints out stats every ten seconds.
• iostat

Error logs

• [bash]sudo nano /var/log/apache2/error.log[/bash]

Apache web server access log statistics

• Webalizer – [bash]sudo apt-get install webalizer[/bash] GeoIP is required for webalizer [bash]sudo apt-get install geoip-bin[/bash] detailed instructions