Step1 : Check Squid is running or not
#ps –ef | grep squid
This command should give you
Five internal dns server running process
Two squid demon(squid –D)
One unlinked process.
If all the mentions process are running fine means, it indicates that your Squid server is running fine.
ps -ef | grep squid
root 31617 1 0 15:06 ? 00:00:00 /opt/squid/sbin/squid -D
squid 31619 31617 0 15:06 ? 00:00:00 (squid) -D
squid 31623 31619 0 15:06 ? 00:00:00 (dnsserver)
squid 31624 31619 0 15:06 ? 00:00:00 (dnsserver)
squid 31625 31619 0 15:06 ? 00:00:00 (dnsserver)
squid 31626 31619 0 15:06 ? 00:00:00 (dnsserver)
squid 31627 31619 0 15:06 ? 00:00:00 (dnsserver)
squid 31628 31619 0 15:06 ? 00:00:00 (unlinkd)
Step2 : Check back end server is able to access from your reverse proxy or not?
#links web425.example.co.in
Step3 : Check system default logs for any suspected activity.
#tail –f /var/log/messages
Step4 : Check squid access logs, cache logs, store logs if you can able to find any issues
#tail –f /opt/squid/var/logs/access.log
#tail –f /opt/squid/var/logs/cache.log
#tail –f /opt/squid/var/logs/store.log
Step5 : Check whether your syntx in squid is fine or not with the following commands
/opt/squid/sbin/squid -k check
/opt/squid/sbin/squid -k parse
/opt/squid/sbin/squid -k parse
