Linux Rescue Mode – How To

A couple of my System Admin friends asked me a question on how to get into the Linux Rescue Mode.  Hence thought of publishing the steps to start rescue mode in Linux.

1. Insert 1st CD of Linux (Red Hat Flavor) and boot the server from CD.  In case if the server is located at remote site, you can create an ISO image of the CD and attach the CD Image through the console (ILO in case of HP, IMM in case of IBM and DRAC in case of dell servers) .  The ISO image also can be attached to a Virtual Server (VMware) by double clicking on the CD icon on the right bottom side of the console.
   


2. Type linux rescue at the prompt and click enter.                                                                                                                                                                    


3. The mini kernel would be loaded from the CD and it would prompt you to select the desired language.  Please select the desired language, select “OK”.                                                                                                                                                                                                                          


4. The setup program would prompt you to select the Keyboard Type.  Please select the Keyboard Type and select “OK”


5. Now the setup program would ask you if you need network interfaces to be active in rescue mode.  Most of the time it is not required, but if you want to copy data or if there is any need to download any files in the rescue mode, you can select “Yes”.  Select the desired setting by selecting “Yes” or “No”


6. By default, Rescue Mode would search for the previous Linux Environments and mount the file system under /mnt/sysimage.  If for some reason, you do not want the setup program to find the Linux File System and mount them under /mnt/sysimage, please select skip.  If you don;t want to modify any existing files, select “Read-Only else select “Continue”
   


7. If you have selected “Continue” or “Read-Only” in previous option,  you would get the following screen notifying you that the previous system has been mounted under /mnt/sysimage.  Select “Ok” to get a shell prompt. If you would have selected “Skip” in previous step, you would get a shell prompt.   From the shell prompt you can troubleshoot and fix if there are any problems (like inconsistent file system(s) etc).  If you wanted to access your previous system’s root environment, execute command “chroot /mnt/sysimage” and you would get all your file system and previous environment
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