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6.2. Setting the root password

By default, the root login and password are disabled on RHEV Hypervisors for security reasons. During unattended installs, there is no way to override this and set the root password at install time. In some circumstances, however, having root access to the RHEV Hypervisor host is necessary for debugging and support. To work around this, administrators must first gain temporary root access to the RHEV Hypervisor host, then set the password.
  1. Gaining temporary root access

    • Method 1: SSH using a key pair. This procedure is run from the RHEV Manager server.
      1. Download the latest versions of putty.exe and puttygen.exe to your RHEV Manager server from
      2. Use puttygen to generate a new private key.
        1. Run puttygen.exe. From the top menu, select conversion -> Import key
        2. Select C:\Program Files\RedHat\RHEVManager\Service\ca\keys\rhevm.pem
        3. Enter the passphrase for this key: mypass
        4. Click save private key
      3. Use the private key to connect to the RHEV Hypervisor host.
        1. Run putty.exe. Enter the IP address of the RHEV Hypervisor host you wish to connect to.
        2. From the left panel select SSH -> Auth
        3. Browse to the private key you just generated, click open
        4. Enter the username root and use the password mypass. Open the SSH connection. You should now have a root shell open on the RHEV Hypervisor host.
    • Method 2: Boot into rescue mode. This procedure requires physical access to the RHEV Hypervisor host, and is run from its physical console.
      1. Reboot the machine and wait for the GRUB prompt. Hit enter to interrupt normal booting.
      2. Modify the kernel line to boot into rescue mode. To do this, append the string rescue to the kernel line, separated from the rest of the line with a space character. Once the system boots, you will be dropped to a a single user root shell. The system must be rebooted into multi-user mode after following the instructions below.
  2. Setting the root password

    Once you have successfully gained root access, you can set the root password for future use.
    1. Run the command setup
    2. Select option #1 Configure authentication
    3. Select option #2 Toggle SSH password authentication
    4. Enable SSH password authentication
    5. Select option #1 Set administrator password
    6. Enter your new root password
    7. Select option #3 Return to the Hypervisor Configuration Menu
    8. Select option #7 Exit Hypervisor Configuration Menu