Bare metal restore with software RAID is very difficult

[aj_potc]

The name of the tool, for example. I also wonder whether you could plug an ISO via IPMI from your side, and if that would work.

They won't tell me the name of the tool, unfortunately. They say it's self-developed, but I'm sure it's based on one of the open source projects. The mounting of an ISO via IPMI seems to be disabled in their KVM. I think it's because of the slow speed and finnicky nature of it, so they just don't allow it.

Our team is also still digging, please let us know of you see anything interesting in the extended boot log.

Removing the quiet parameter does give me more details, but nothing interesting. However, I make a small breakthrough:

I used the parameter ignore_loglevel, which should have the effect of ignoring whatever log level is set during the boot process. I figured this would give me even more verbosity.

However, incredibly, when I use this parameter on my CentOS 8 patched ISO and your unpatched recovery media with the version 5 kernel, the system boots (it still won't boot with the unpatched v4 kernel). That makes no sense to me, as I'm only changing the log level on the console, right?!?!? But at least it's a step forward.

Even though I'm able to boot the media, volume recoveries are still glacially slow (about one-quarter the expected transfer speed). I suppose there's another cause for that, and I'm hoping your support can help.

Thank you.

[PTide]

Our guys have confirmed the described behaviour. Here are the steps to reproduce:

1. Get ISO ('wget' for example)
wget https://repository.veeam.com/backup/lin ... -5.0.0.iso

2. Burn the ISO on the mounted flash drive with 'dd':

Code: Select all

sudo dd bs=4M if=/path/to/veeam-recovery-amd64-5.0.0.iso of=/dev/sdx status=progress oflag=sync

Here if you omit the 'sync' flag the USB media won't boot with the same symptoms that you saw.

Any chance that the techs in DC could try the proposed method?

Thanks!

[aj_potc]

Hi @PTide,

I appreciate the suggestion, but unfortunately this didn't make a difference in my case.

I tried writing out the ISO to the flash media using the command you suggested from a Debian 9 system, but I'm unable to boot either kernel (4 or 5) when selected from the Grub menu.

Edit to add:
I tried adding the kernel parameter ignore_loglevel, which previously allowed the version 5 kernel to boot. But this time, that parameter doesn't help. Here's a screenshot of the result:



Thanks.