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ESX host boot stops at the error: VSD mount/Bin/SH:cant access TTY job control turned off (1012874)


  • An ESX 4.x host becomes unresponsive when it is put into maintenance mode.
  • Rebooting the host fails.
  • On the ESX console, you see the error:

    VSD mount/bin/sh:can't access TTY; job control turned off.
  • The ESX host does not boot and drops into Troubleshooting (busy box) mode.
  • The last lines in the /var/log/messages log file are similar to:

    sysboot: Getting '/boot/cosvdmk' parameter from esx.conf
    sysboot: COS VMDK Specified in esx.conf: /vmfs/volumes/4b27ec62-93ec3816-0475-00215aaf882a/esxconsole-4b27e9e3-20ee-69d7-ae11-00215aaf882a/esxconsole.vmdk
    sysboot: 66.vsd-mount returned critical failure
    sysboot: Executing 'chvt 1'


This issue occurs if an ESX host cannot identify the esxconsole.vmdk file in which the service console resides. 


This issue is resolved in ESX 4.0 Update 3 and ESX 4.1 Update 2.

Important: If your ESX is booting from SAN, the service console must be installed on a VMFS datastore that is resident on a host's local disk or on a SAN disk that is masked and zoned to that particular host only. This datastore cannot be shared between hosts. For more information, see the ESX and vCenter Server Installation Guide. Verify these requirements are met before continuing with the troubleshooting.
To attempt to work around the issue without updating the ESX host:
  1. Go to the console of the ESX host. After the error message, ESX drops into Troubleshooting (busy box) mode.
  2. Find the .vmdk for the service console by running the command:

    # grep "/boot/cosvmdk" /etc/vmware/esx.conf

    The output is similar to:

    /boot/cosvmdk = "/vmfs/volumes/<uuid>/<dir>/esxconsole.vmdk"

    For example:

    /boot/cosvmdk = "/vmfs/volumes/4a14d968-88bf7161-700f-00145ef48f76/esxconsole-4a14d906-2f96-7956-7284-00145ef48f74/esxconsole.vmdk"
  3. Make note of the <uuid> and the <dir> values in the output.
  4. Verify that the files exist by running the command:

    # ls -al /vmfs/volumes/<uuid>/<dir>/*.vmdk

    Where <uuid> and <path> is from the output of step 2. 

    The output is similar to:

    total 7906560
    drwxr-xr-x 1 root root        840 May 21 00:45 .
    drwxr-xr-t 1 root root       2660 Oct 21 09:10 ..
    -rw------- 1 root root 8095006720 Oct 26 15:37 esxconsole-flat.vmdk
    -rw------- 1 root root        475 May 21 00:32 esxconsole.vmdk
    drwxr-xr-x 1 root root        980 May 21 00:45 logs

    Note: You may receive the error: ls: /vmfs/volumes/4a14d968-88bf7161-700f-00145ef48f76/esxconsole-4a14d906-2f96-7956-7284-045ef48f74/: No such file or directory. If the directory does not exist, see ESX fails to boot when the disk containing the datastore with esxconsole.vmdk is detected as a snapshot (1012142).
  5. Ensure that the esxconsole-flat.vmdk  

    If the esxconsole.vmdk file does not exist, see Recreating a missing virtual disk (VMDK) header/descriptor file (1002511) and ensure that the following settings are in place:
    • ddb.adapterType = "buslogic"
    • ddb.consoleOsDisk = "True"
  6. Ensure that the esxconsole-flat.vmdk exists.

    Note: If the esxconsole-flat file does not exist, you must reinstall ESX to recreate the service console.
Note: If reinstalling ESX is required and virtual machines or other important data reside on the local storage, ensure to select the Preserve VMFS option during the installation. This ensures that any local VMFS partition is left untouched.



See Also

Update History

05/12/2010 - Added /var/log/messages entries to Symptoms; Added information about booting from SAN. 05/06/2011 - This issue is resolved in vSphere 4.0 Update 3. 01/25/2013 - Added note about selecting the Preserver VMFS option 09/26/2013 - This issue is resolved in vSphere 4.1 Update 2.

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