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Converting Centos 6 HVM to PVM issue

Gerry Maddock


We have (3) centos 6 vm's that were setup as HVM and I was able to successfully convert 2 of the 3 to PVM. the other wont boot after it is changed to PVM and I have to convert back to HVM for it to boot. I have searched the internet and didn't see a resolution for this one:

 Starting VM 'SFTPV1T' Internal error: xenopsd internal error: Memory_interface.Internal_error("VM = cfbc2ca6-0ffe-7682-599a-712873ef2e1f; domid = 40; Bootloader.Bad_error No valid Btrfs found on /dev/sm/backend/c6bbf0ae-e692-0158-a535-a7b6a4779adc/a6fc07ac-ad26-4f1b-b8a6-ca18cdccd635\nNo valid Btrfs found on /dev/sm/backend/c6bbf0ae-e692-0158-a535-a7b6a4779adc/a6fc07ac-ad26-4f1b-b8a6-ca18cdccd635\nSuperblock bytenr is larger than device size\nTraceback (most recent call last):\n File \"/usr/bin/pygrub\", line 990, in <module>\n fs = fsimage.open(file, part_offs[0], bootfsoptions)\nIOError: [Errno 95] Operation not supported\n") Time: 00:00:04 FEXEN2 Apr 22, 2019 2:22 PM Dismiss


What I have done:

1.) I have removed all snapshots and retried without luck.

2.) I created a snapshot, then created a new vm from the snapshot and retried on the new vm with no luck.


Any help would be greatly appreciated.

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1 hour ago, Gerry Maddock said:

Alan, did you mean this one: 

pygrub can't find the first boot paririon, so try this:

xe vm-param-set  uuid=[vm-uuid] PV-bootloader-args="--offset=1048576"


offset = 2048s*512b/s=1048576b

    Device Boot      Start         End      Blocks   Id  System /dev/xvda1   *        2048     2099199     1048576   83  Linux

If so, I just tried that (my disk had the same 512 bytes sectors and the same start sector of 2048 so I added: PV-bootloader-args="--offset=1048576" and retested with no luck (same issue). Thank you for your suggestion so far ;)


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