VMWare vSphere

Use MBR disk in ESXi 5

1 min read15 comments

From ESXi 5.0, if you install ESXi to a empty hard disk, the target disk will be prepared with GPT-based partitions. That may cause some boot delay or even boot problem in some desktop motherboards.
Fortunately, you can use MBR mode instead of GPT.

Step:
1 Make a clean hard disk for ESXi. You can use any method to delete all partitions on that disk.
2 Boot with ESXi CD. During initial installation step, press Shift-O (letter, not number zero) when prompted (right down corner).
3 Type a space and "formatwithmbr" (without quotation marks). Press enter.
4 Go on setup. ESXi will make the target disk prepared with MBR-based partitions instead of GPT.

15 comments

    1. AllenAuthor

      Check the right down corner of the picture above.

  1. Eugene

    Thanks a billion! Works perfect even without erasing HDD before installation!

  2. natraj

    the option should be "runweasel formatwithmbr"

    1. AllenAuthor

      runweasel is predefined and you don't need to touch it.

  3. anatol

    Hi,
    I have lost my MBR after update from version 5.0 to 5.1 Now start is only possible by using Install CD with "boot from disk"-option. The updated system (5.1.1) works fine and I don't want to reinstall it completely via this option (Shift-O). Is any other possibility to repair of MBR only?
    Thank you in advance.

    1. AllenAuthor

      This may help: http://support.microsoft.com/kb/69013
      MBR is OS independent, except the text displayed while OS missing.

      Or, try this to copy a MBR from another server running ESXi: https://wiki.archlinux.org/index.php/Master_Boot_Record#Backup_and_restoration

  4. HaKa

    Hm - tried it quite several times - everytime after 10% of the installation progress, the installation fails with an error message:
    "
    Unable to successfully execute 'retryWrites' after 3 tries.
    Installation cannot continue
    "

    Any ideas?

    1. AllenAuthor

      Try to install on another hard drive.

    2. Clint Young

      I got the same error. I re-formatted with the HP USB Disk Storage FOrmatter, and then formatted it AGAIN with Rufus (check sourceforge) and ran the 2 pass pattern verification, which passed. Tried to install again, and went smoothly. Best of luck.

    3. AllenAuthor

      Another possible reason is: you're using a CDRW for installation media. Try to use CD-R or network boot instead.

      I dont know the reason. Actually, I never succeeded install ESXi from CDRW media. I know all data is correct. Even trying to install with one CDR copied from this CDRW is successful.

    1. AllenAuthor

      GPT is not supported by all motherboards. In some case, have to use MBR.

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