Troubleshoot Your Linux VPS
This section describes how to troubleshoot general issues as well specific problems you encounter as you operate
your Linux VPS. This section provides information about troubleshooting the following problems on you account:
General Issues
Always remember where you are located now in your command interface. Check it periodically using the pwd, hostname,
ifconfig commands. The same command executed inside your private server, under a different level of access, can lead
to different results. Subscribe to bug tracking lists for RHEL and the additional, supported features you install on
your private server. Keep track of new public denial-of-service attack tools or remote exploits for the software and
install them into your private server or at the server level.
Failure to Create a Virtual Host
If your attempt to create a new virtual host fails and you see a message indicating that the operating system template
is absent or inaccessible, verify the location of the template on your system and, if necessary, re-install the
template.
Check Quotas
When your private server meets quota limits, the disk cannot be written to. Your private server cannot accept email,
log files, or complete installations. Your quota has a soft limit (which you temporarily exceed) and a hard limit
(which you do not exceed).
Check Log Files
Your private server records all errors and system messages in log files. If you or your users are having problems on
the account, first check the quota; then check the log files. If the problems concern email, check the
/var/log/maillog file. Problems with the Web site are recorded in the /www/logs/error_log file.
Use the tail command to watch error messages as they are added to log files. Note what is being added to the log
files as the user duplicates the error. Follow these steps to use the tail command:
- Connect to your private server using SSH.
- At the command prompt type tail -f /var/log/maillog. (If necessary, substitute the messages directory with
/www/logs/error_log, /access_log, or the /ssl_error_log files.)
Have the user duplicate the error while you are running the tail command.
Check for Idle Processes
If you are receiving errors, use the top command to check the length of time a current process has been running. If
the process is idle or has been running an unusually lengthy period of time, the process could be suspended and
causing problems. For example, an FTP process can hang if you improperly disconnect from your private server. Use
the kill command to shut down a suspended process.
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