Using Repair Mode


  • All DV
    • Difficulty: Medium
    • Time Needed: 30
    • Tools Required: Your server's root password, access to your Plesk Power Panel

What is Repair Mode?

Repair Mode is a handy tool that is natively available on all DV servers. It allows you to navigate your server's file system while your actual server environment is offline.

Why is Repair Mode useful?

The two biggest advantages to Repair Mode are:

1) Dealing with disk space issues where your server is at 100% utilization and can not be managed in production.

2) Making changes to the boot sequence to alter the state your server will start in when it is brought online. However, there is no limit to the specific situations where this tool may be useful.

Yes, SSH is Required

In order to make use of Repair Mode, you must have a fundamental understanding of using SSH with your server. Please see "Additional Resources" below for more info.

READ ME FIRST

This article is provided as a courtesy. Installing, configuring, and troubleshooting third-party applications is unsupported by (mt) Media Temple. Please take a moment to review the Statement of Support.

Instructions

1. To get started, navigate to the "Parallels Power Panel" (a.k.a. "Virtuozzo"). You can reach the panel by going to https://0.0.0.0:4643 in your web browser (please replace the "0" characters with your actual IP address). More information can be found here.

2. You must log into the panel as the root user. If you do not know your current root password, you must reset it via the (mt) AccountCenter.

3. To proceed, you will need to confirm the SSL/security exception in your browser (this is expected). More information can be found here

4. Once you are actually logged in, click on the "Maintenance" link on the lefthand side.

5. Open the "Repair Mode" option and select "Start Repair". Note: If your server is still online, this will take it offline so that the file system can be mounted.

6. Once the server has successfully entered this mode, you can SSH to it as the root user.

Note:You may encounter a warning that contains the following:

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that the RSA host key has just been changed.
This is due to your ssh command using strict fingerprint checking (the default setting on most systems) and the mount point of your file system not identifying itself with the same information as your server. This is correct and expected, because it is not the same thing. To work around this, you either need to edit your existing host file to re-accept the fingerprint presented by the repair system, or use the following flag on your ssh command (substitute your server's IP address):

ssh -o StrictHostKeyChecking=no root@0.0.0.0

7. Once you complete the SSH connection, you will find your server mounted in a special directory, /repair. Referring to the earlier examples, this means the following types of actions are available:

A file located at /var/www/vhosts/example.com/httpdocs/largefile needs removed because it will safely take your disk usage under 100%. This can now be accomplished using:
rm /repair/var/www/vhosts/example.com/httpdocs/largefile
Your server is crashing immediately upon rebooting and you would like to temporarily remove the ability for Apache to start:
chmod -x /repair/etc/init.d/httpd

8. After you have completed the changes necessary, you can revisit your Power Panel and "Finish Repair". This will remount your file system to your server environment and attempt to boot the system. If this is successful, your server will be back in a standard state.

Additional Resources