Unbootable host after updates. Not even getting to grub?

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dbhosttexas
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Unbootable host after updates. Not even getting to grub?

Post by dbhosttexas » 2018/08/01 18:13:26

So last thursday, we were doing normal maintenance activities, patching etc... when 2 nodes of a cluster were patched and sent down for reboot. Neither host came back online. I can access them via iLO and I keep getting sent over to a no OS found prompt and it tries to boot from PXE.

I booted to the install disk, and tried to reinstall grub with no change in behavior.

I am trying to not reinstall these hosts as they are very poorly documented, not backed up. And the setup of them is quite complex.

I am looking for any advice on how to restore these hosts to production if at all possible. Thanks.

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TrevorH
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Re: Unbootable host after updates. Not even getting to grub?

Post by TrevorH » 2018/08/01 19:24:48

Boot from the install media in rescue mode and get it to mount the system partitions for the installed system under /mnt/sysimage and explore there.
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dbhosttexas
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Joined: 2014/09/23 20:59:25

Re: Unbootable host after updates. Not even getting to grub?

Post by dbhosttexas » 2018/08/01 20:31:08

Been there, done that, bought the T shirt. The big issue is, these are UEFI hosts, and documentation on reinstalling grub on UEFI is a bit sketchy... Been looking, but no joy.

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TrevorH
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Re: Unbootable host after updates. Not even getting to grub?

Post by TrevorH » 2018/08/01 22:08:02

Yes but you need to mount the partitions to look at what's there. For a start is there anything there at all? Is the disk still partitioned? Does it recognise any LVM LVs? Can you run fdisk -lu /dev/sd[a-z] and post the results?
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