Bug 376691

Summary:	Please document the domdadm boot parameter
Product:	[OLD] Docs on www.gentoo.org	Reporter:	Andre Kloth <bugs-gentoo>
Component:	Other documents	Assignee:	Sven Vermeulen (RETIRED) <swift>
Status:	RESOLVED FIXED
Severity:	normal	CC:	docs-team
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
URL:	http://www.gentoo.org/doc/en/gentoo-x86+raid+lvm2-quickinstall.xml
Whiteboard:
Package list:		Runtime testing required:	---

Description Andre Kloth 2011-07-28 08:58:37 UTC

If you follow this guide and create e.g. a RAID 1 for /boot with metadata 0.9, but swap and / RAIDs with metadata 1.2 (mdadm default value), your system won't boot after installation. You have to manually assemble the RAID 1 for / in the Busybox shell of initramfs.

However, you can circumvent this problem by adding "domdadm" to the kernel boot parameter list. The initramfs (which is created by genkernel) will then assemble all RAIDs according to the previously configured /etc/mdadm.conf.

If you don't use genkernel, you must prepare your own initramfs in order to get a / with metadata 1.2 mounted at startup. An example of such initramfs is at: http://forums.gentoo.org/viewtopic-p-6767430.html

Reproducible: Always

Steps to Reproduce:
1. Build RAID 1 with metadata 0.9 for /boot
2. Build RAID 1 with metadata 1.2 for swap and /
3. Try to boot the system according to the RAID quickinstall guide

Comment 1 Sven Vermeulen (RETIRED) gentoo-dev

2011-08-23 15:00:43 UTC

Actually, the guide mentions the use of 0.90 for / and /boot, which should work (I use it on my laptop without initramfs without problems). But I'll add the domdadm information to the guide.

Comment 2 Sven Vermeulen (RETIRED) gentoo-dev

2011-08-23 15:12:37 UTC

Fixed in CVS. This should show up in an hour or so online.