Bug#335230: [#335230] How to actually support EVMS in an initrd

[Marco Amadori <marco.amadori@gmail.com>]

Alle 21:18, sabato 22 ottobre 2005, Steinar H. Gunderson ha scritto:

> EVMS support in yaird should not be difficult to add for someone who
> already knows yaird. Basically, what you need to do is:

We need a perl hacker.

Code speaking, I'm not a perl hacker, too bad, but I understood that, looking 
at yaird coding style a new file EvmsTab.pm should be added to sources that 
does what you are saying. A new function tryEvms should be added to Plan.pm.

>  - If root= is not /dev/evms/*, _do not do anything in the initrd_. If you
>    do, you _will_ break root mounting for anybody _not_ using root on EVMS.

This is done with the should-be-added-line 88 in Plan.pm:

	$ok || ($ok = tryEvms ($actions,$device,[$device,@{$working}]));

>  - Make sure /dev/ is writable, and mkdir /dev/evms.

Translate this in perl plz :-)

>  - modprobe -q dm-mapper to load the devmapper module. You might also want
>    to modprobe raid0/raid5 if the system in question needs that for /.

the module name is the same as lvm: dm-mod
to query for info on device found in fstab we can use evms_query, it reports 
also the plugins from /lib/evms/version/ that should be copied.

# evms_query info sdc9 #my root partition btw
Name: sdc9
Type: Segment
Data Type: Data
Device Number: 253,17
Size (sectors): 835317
Plugin: DosSegMgr

>  - Run /sbin/evms_activate (from the “evms” package). It will do partition
>    discovery and mknod the appropriate devices in /dev/evms.

First if the root device is /dev/evms/lvm2 also vgchange -a y should be 
launched before that, right?

-- 
ESC:wq