6 Replies Latest reply on Oct 9, 2013 6:28 PM by JeffInouye

    Ignore missing virtual disk and boot anyway?

    byroncollege Lurker

      Hi all,

      Is there a way to make an ESXi guest ignore non-critical missing virtual hard disks and boot anyway. At present there are some mapped iSCSI drives that are not critical to a server being up. If there is a power failure and the iscsi target has a problem, the guests fail to start automatically.

      I have to remove the drives and boot them manually.


      Many Thanks

        • 1. Re: Ignore missing virtual disk and boot anyway?
          JeffInouye Enthusiast

          Is there a reason that the target wouldn't be available?  Does it also get halted when the power gets dropped?  If so I would consider a power up order on the host.  Is this a standalone host?  What type of guest OS are you working with?

          • 2. Re: Ignore missing virtual disk and boot anyway?
            byroncollege Lurker

            Hi Thank for responding. No there is no reason it wouldn't be available. Its just from an up time point of view. Its only a small setup, and the critical disks are housed within the machine and then there are old archives/backups etc hosted on the freenas box.

            Its more important that the machine boots than wait for the nas to come back. Not often but sometimes the nas will have an error after a power outage etc that requires administrative intervention. In this case the VM should just start to ensure the critical services are booted. Is it possible to get a a VM to just continue to try and boot until the drive comes online too? In case there is a long delay or filesystem rebuild.

             

            The Guest VM's are Windows Server 2012.

            • 3. Re: Ignore missing virtual disk and boot anyway?
              continuum Guru
              User ModeratorsvExpertCommunity Warriors

              just an idea ....

               

              VM A has critical.vmdk, optional1.vmdk,optional2.vmdk

              VM B has critical.vmdk

               

              autostart VM A and VM B - with a long delay

               

              with the correct settings for both VMs - uuids must be the same and uuid.action = "keep"  must be set - it may work.

               


              I doubt that setting bios.bootRetry.delay or other vmx - parameters wil lhelp you.

               

              Best option I can think off: run a cronjob that pings the iscsi-target and depending on the result sets
              scsi0:1.present = "true" or "false" in the vmx-file.
              Then you would not need a second VM ...

              1 person found this helpful
              • 4. Re: Ignore missing virtual disk and boot anyway?
                JeffInouye Enthusiast

                I would consider a cifs share on the freenas and then go with a startup script to use it as a network drive.  I'm curious as to why the OS won't boot when the iscsi drives don't connect?  I dont believe i have encountered that issue.

                1 person found this helpful
                • 5. Re: Ignore missing virtual disk and boot anyway?
                  byroncollege Lurker

                  Thanks Continuum ill look into that.

                   

                  Jeff, Its not the guest OS's problem, ESXi itself throws an error when it can't find one of the attached hard disks (even if it is not the boot drive). i.e "cannot find hard disk 3 xxxx.vmdk" and then it just terminates the boot process. I've thought about a CIFS share (may be the way I have to go) or direct mounting the iscsi share in the guest os, but whitepapers often advise against this.

                  • 6. Re: Ignore missing virtual disk and boot anyway?
                    JeffInouye Enthusiast

                    Yeah, I follow you now.  cifs and iscsi seem like they would be a good option.  Out of curiosity what software whitepapers are you referring to?  I'm trying to think of why they would be against it.