[CentOS] Centos 7, grub2-mkconfig, unsupported sector [followup]

Tue Dec 29 21:43:10 UTC 2015
m.roth at 5-cent.us <m.roth at 5-cent.us>

m.roth at 5-cent.us wrote:
>    Well, I get back from vacation, and three CentOS 7 boxes didn't come up
> this morning (my manager and the other admin did the update & reboot).
> On these three - but *not* another one or two, and I don't think those
> others are Dells, they're supermicro's - the 327 kernel fell into the
> rdosshell, I guess. I finally got one the three up by going back to the
> 228.14 kernel.
>    Now, after googling and finding the CentOS bugzilla, 0009860, that
> referenced the upstream bugzilla, I applied the workaround discussed in
> it, Adding initcall_blacklist=clocksource_done_booting to
> GRUB_CMDLINE_LINUX in /etc/default/grub and then grub2-mkconfig -o
> /etc/grub2.cfg"
>    On one. On the other, that's got a *large* RAID appliance (a JetStor w/
> 42 4TB drives...), it seemed to work... then gave me a dozen or so
> ERROR: unsupported sector size 4096 on /dev/sdd.
> ERROR: unsupported sector size 4096 on /dev/sde.
>    0. Did the grub2-mkconfig actually work correctly?
>    1. Is it safe to ignore the errors and reboot?
>    2. This seems to be an old bug in os-prober, that was fixed
>          years ago - has it slipped back in?

No joy. I followed the workaround instructions... and by late afternoon,
the system was in distress, with the time *far* off among other things
(like an hour off).

Interesting notes:
 this morning, from the rsdosshell with the new kernel, I had to power
cycle, and tried to boot the ...20 kernel, and it failed, as well. This
time, rebooting from a running system, I was able to boot that kernel
with no problem.

 When I went to choose this kernel, I also one-time deleted the workaround.

At least on these servers, I've removed the current 327 kernel, and we're
staying on the 20 kernel. We'll see what happens with the next kernel.

I also removed the workaround from grub,

There's still the question of why os-probe, which was supposedly fixed
almost five years ago, according to what I google, is back to complaining
at 4k sectors.