How to clean up full /boot safely?

[Liam Proven]

On 12 February 2018 at 11:53, Colin Watson <cjwatson at ubuntu.com> wrote:
>
> There are conceivably some similar kinds of requirements on more recent
> systems.  For instance, it's possible to use GPT on most non-UEFI
> systems with a bit of luck and a following wind, and thus make use of
> disks larger than 2TB; but if you do that then you need to make sure
> that /boot is in the bottom 2TB of the disk.

Good point.

> This was the traditional requirement, but GRUB is quite a bit more
> powerful these days and can read more than just straightforward
> filesystems.
>
>> Things GRUB might have problems with:
                               ^^^^^^

I stress the _might_ part...

> All your examples are supported by GRUB.
>
> Of course it's necessary for GRUB to track on-disk format changes, and
> the more code you're relying on in the boot loader the more there is to
> go wrong, so it's true that there "might" be problems

> Things like
> LVM are pretty safe these days

"Pretty"

> (Of course, there might also be problems even with what you might view

"Might be"

>> * filesystems which are encrypted
>
> This is supported by GRUB, although it does mean entering your
> encryption passphrase twice.

"Although"

> may not consider this to be worth it.  (It's possible to avoid this

"Possible"

> In principle all this should be fine with GRUB >= 2.02;

"Should be"

That's the thing.

I'm a pretty old hand now.

I have 2 slightly different perspectives.

[1]

I was a sysadmin and the like for *decades.*

As such, I just won't tolerate "might" and "should" and "ought to" and
"probably".

I insist on "absolutely will always without fail" except for hardware
failure, major disk corruption etc.

[2]

I'm old and grumpy and lazy and my desktop is a Mac on which I run
macOS {$CURRENT-1 release}

I don't trust Apple not to fsck up the version they are currently
fiddling with. So I run the _superseded_ version which gets a lot
fewer breakages, and if there are breakages, well, they're historical
which means everyone knows and works around them and they are easy to
find on Google.

I want to go to the absolute minimum effort.

That means not "trying" stuff that "should" work on specified recent
versions of stuff or that requires any extra steps from me
_whatsoever_.

I want stuff that just *does* work, on any currently supported version
of any mainstream OS or distro,

Which is what makes me a bit nervous of ZFS itself because only Ubuntu
supports it, other distros eschew it, and it's thus nonstandard. Those
words all set off alarm bells.

But it's in FreeBSD and they are super-conservative. The sort of
greybeard elder geeks I know who regard me as dangerously radical like
and trust ZFS, and I trust them.

> I would try /boot on ZFS, but be
> prepared to fall back to a traditional separate /boot in case of
> problems.

You see, a comment like that makes me think "not a chance in hell". No
way, José. Nope.

No, the box will boot off a separate dedicated non-RAID volume, using
something boring and totally non-experimental like ext4, so if
anything weird happens, it will still come up and I can connect to it
and fix it.

-- 
Liam Proven • Profile: https://about.me/liamproven
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