Most of the issues which arise are due to configuration errors and ambiguous configurations, which are known as Squid bugs or operating system issues. You can fix these issues quickly if you are aware of the issues which are commonly faced by Squid users, as these types of issues generally have standard solutions. So, let's have a look at a few common problems.
Sometimes, while starting Squid, we may get a warning similar to the following:
WARNING: Cannot write log file: /opt/squid/var/logs/cache.log /opt/squid/var/logs/cache.log: Permission denied messages will be sent to 'stderr'.
This generally happens when the user running Squid doesn't have write permissions to the directory containing log files or the log files themselves. This error can be avoided to a large extent if we use binary packages for our operating system because the permissions and ownerships will be set up properly by the packet installer during installation.