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#Boot-up your c7host. As soon as the Grub Boot menu appears, press the letter '''e''' (for "edit").
#Using your arrow keys, move to '''linux16''' command and replace command arugment type the word '''rosingle''' with as an argument after '''rw init=/sysroot/bin/shquiet''' (see diagram for reference) and then press '''ctrl-x''' to boot.#The system should take you to a command promptboot into text-based mode. Enter your root password. At the command prompt enter: '''chroot /sysroot'''
#One thing to look at is partition space usage. Issue the command: '''df -h'''
#If you notice 0% free space in the / partition, then there is a problem. This most likely is caused by not following steps to create a <u>compressed</u> copy of the VM image. If that is the case, locate the large image backup and remove it. Do NOT remove the image in ''/var/lib/libvirt/images'' directory!
#Then simply type You can use the command '''rebootpasswd''' command to reset your regular user password (eg. passwd yourusername).#To restart the machine (hopefully in graphical mode), simply enter the command '''reboot'''.
#The procedure to reset root's password is different than shown above. Press '''e''' at the Grub boot menu.#Using your arrow keys, move to '''linux16''' command and replace the argument '''ro''' with the argument '''rw init=/sysroot/bin/sh''' (see diagram for reference) and then press '''ctrl-x''' to boot.#The system should boot into text-based mode without prompting for root's password.#Issue the command::For example:'''chroot /sysroot'''
#Issue the command::*passwd root in order to change your root password.#To restart in graphical mode, simply enter the command '''passwd rootreboot'''. ::*'''passwd usernameCatastrophic Boot Problems:'''
:Not being able to start your c7host due to Kernel Panic or some sort of "catastrophic disk failure" is not as easy to fix. You might be able to boot from your Centos LIVE DVD, open a terminal and mount the partition via command line and look for possible problems (setup files like /etc/fstab). Lab5 will discuss more about mounting and the /etc/fstab file. The "worst-case scenario" would be to purchase a new hard disk, perform lab1 completely, perform lab2 to install and set-up virtualization software, then restore your VM image and xml file backups (eg. decompressing images, issuing virsh define commands for xml files). That is why consistently performing backups of ALL of your VMS at the end of each lab is absolutely essential! You have been warned!