Guillaume Cottenceau wrote:
>>I did not know what it does. Besides, I suspect that for LVM you can't
>>use device numbers, you have to use real names. Numbers are assigned
>>dynamically when volume group is configured; if we rely on vgscan it may
>>find another VG first, so minor number will be wrong.
>>
>
> With LVM, once started, do you use "mount" with a device file or something
> else?
>
Of course with device file. Device file has minor number. It is
associated with with volume group when this volume group is activated.
So, if you have VG1 and VG2 then if VG1 is activated first it gets minor
number 0 and VG2 minor 1. If VG2 is activated first, *it* gets minor 0.
Lilo encodes just major/minor for LVM device. But it may happen that
you run lilo, and your root was minor 0
you added one more volume on another disk
when you boot, the secobd disk is seen first and this VG gets minor 0
Brian, is it possible?
>
> 10 Megabytes???
>
> waooh.
>
And absolutely useless because at this point you need to configure
exactly on volume - with root filesystem.
>
>
>> >>3. You cannot shutdown root volume but that's probably just cosmetic
>> >>(warning on shutdown). May be sensible to filter root VG from shutdown.
>> >>
>> >
>> > is the initrd getting umounted gracefully?
>> >
>>
>>What initrd? I speak about LV with root filesystem. You cannot shutdown it
>>until is unmounted. And it is never unmounted (at least, not in any
>>initscript).
>>
>
> With the new mkinitrd, the initscripts will try to umount the initrd
> (located in /initrd) as third or fourth message after init booted.
> (disable aurora to see it well).
>
There is some misunderstanding. I speak about *system*shutdown*. Not
about unmounting initrd - here you have no problems. When system shuts
down it deactivates LVM. It does not work for root device because it is
busy.
> (what do you mean by "tinylibc"?)
>
I've read about it in your description of stage1, may be I forgot the
exact name, sorry. There was comparison how much stage1 takes with glibc
and with another, apparently stripped down, libc. This was called tiny
libc IIRC.
> Anyway, it appears to me like big headache for a seldom use.
>
Well, this was intended for Brian in the first place as he had problems
with rooting on LVM and I hoped it may help. I guess he had reasons to
implement it. Actualy, there is not much headache and I guess it would
be very interesting for enterprise server.
-andrej
