RHEV-M and gpt on RHEL Hypervisor

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we have the following problem:


We have some HS22 blades that should be used as hosts in an RHEV 3 cluster.

Those blades were installed with RHEL 6.2 on local disks. They have UEFI and are using a gpt.

Installation went fine and the blades were configured as described in the RHEV 3 installation guide.

They were even rebooted several time because of a kernel update and some test with the FC storage they are attached to.


Then we added them to the RHEV-M this installation also went without error and the bladed were rebooted and showed up as active in the RHEV-M.


After we rebooted one of those blades because of some hardware problem it would not boot because the filesystem check on bootup could not find the UUID for /boot as it was in /etc/fstab. After commenting this line in fstab the blade booted again but /boot is not accessible.


Parted shows three partitions on the local disk sda3 with lvm (standard rhel installation with swap, home, and root on lvm), one partiton with ext4 and on as fat16 (?)


Model: LSILOGIC Logical Volume (scsi)
Disk /dev/sda: 146GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt

Number  Start   End    Size   File system  Name  Flags
 1      1049kB  211MB  210MB  fat16              boot
 2      211MB   735MB  524MB  ext4
 3      735MB   146GB  145GB                     lvm

/proc/partitions only shows sda and sda3


major minor  #blocks  name

   8        0  142577664 sda
   8        3  141858816 sda3
 253        0   52428800 dm-0

 253        1   67629056 dm-1

   8       16 1073741824 sdb

   8       48  524288000 sdd

   8       32 1073741824 sdc

   8       64 1073741824 sde

   8       80 1073741824 sdf

   8       96  524288000 sdg

   8      112 1073741824 sdh

   8      128 1073741824 sdi

   8      144  524288000 sdj

   8      160 1073741824 sdk

   8      176 1073741824 sdl

   8      192  524288000 sdm

 253        2 1073741824 dm-2

 253        3  524288000 dm-3

 253        4 1073741824 dm-4

 253        5   21798912 dm-5

 253        6     524288 dm-6

 253        7    2097152 dm-7

 253        8     131072 dm-8

 253        9     131072 dm-9

 253       10     131072 dm-10

 253       11    1048576 dm-11                             


According to fstab boot should be on UUID f492a943-cbca-49a7-bd10-fe9167bb2e64 but blkid does not show it:


/dev/block/253:4: UUID="5Lx0LZ-XTtv-Ch2j-kXrG-1Rl8-0pd4-blsrsu" TYPE="LVM2_member"

/dev/block/253:3: UUID="YWRoyg-VBy5-O4cP-w2gU-6j6H-drxc-IUo5C0" TYPE="LVM2_member"

/dev/sda3: UUID="3gSPH5-8SSO-z7nO-uzIC-Q9UJ-n4lI-n17wjf" TYPE="LVM2_member"

/dev/mapper/vg_rhevh02-lv_root: UUID="0d849236-17cf-4e49-aa24-c8f30569c5ad" TYPE="ext4"
/dev/mapper/vg_rhevh02-lv_swap: UUID="2ffb0c30-f597-4278-bf17-49a474183f45" TYPE="swap"
/dev/sdc: UUID="5Lx0LZ-XTtv-Ch2j-kXrG-1Rl8-0pd4-blsrsu" TYPE="LVM2_member"
/dev/sdd: UUID="YWRoyg-VBy5-O4cP-w2gU-6j6H-drxc-IUo5C0" TYPE="LVM2_member"
/dev/sde: UUID="n66IdL-tCFS-Np0e-P8Vl-3r11-IYqe-QDm3qy" TYPE="LVM2_member"
/dev/mapper/360080e5000241f88000002244ecfc6ca: UUID="n66IdL-tCFS-Np0e-P8Vl-3r11-IYqe-QDm3qy" TYPE="LVM2_member"

/dev/mapper/vg_rhevh02-lv_home: UUID="0f387474-e3dd-44db-ab9a-2aadce90f08c" TYPE="ext4"
/dev/sdh: UUID="n66IdL-tCFS-Np0e-P8Vl-3r11-IYqe-QDm3qy" TYPE="LVM2_member"
/dev/sdl: UUID="5Lx0LZ-XTtv-Ch2j-kXrG-1Rl8-0pd4-blsrsu" TYPE="LVM2_member"
/dev/sdm: UUID="YWRoyg-VBy5-O4cP-w2gU-6j6H-drxc-IUo5C0" TYPE="LVM2_member"
/dev/mapper/45a7ca1a--d836--4e8a--b3e8--866d5b514eda-master: UUID="4e21dbed-9254-4995-a110-20abf0f4a1cf" TYPE="ext3"


After checking the other blades (which did not have hardware issues) we noticed the same problem on them.

How can I get boot back?






To answer my own question:


It was multipath. Blacklisting the FC devices and rebooting made the partitions on the local driver reappear. I still do not know why but know it works and I was able to install the RDAC driver to make multipath work.





Thanks for the follow-up to your issue.

I am extremely curious though... do you have any idea how on earth your host could boot without a /boot?  ;-)


sda1  vfat  /boot/EFI

sda2  ext4  /boot

sda3  lvm  / and <swap>


Did you comment out the line with the UUID and replace it with the device and slice (aka /dev/sda2)?


Either way - I'm glad that you were able to work through the issue.


Which RDAC driver? scsi_dh_rdac comes built into multipath, so it sounds a bit surprising to me, that you needed to install it.