Gentoo Archives: gentoo-user

From: Pau Peris <sibok1981@×××××.com>
To: gentoo-user@l.g.o
Subject: [gentoo-user] Fakeraid + lvm + openrc questions
Date: Tue, 14 Dec 2010 23:04:47
1 Hi, i'm currently running Gentoo on a RAID0 setup on some Sata disks
2 using a Jmicron chip from an Asus P6T board. I'm using a fakeraid due
3 to dualboot restrictions. My whole Gentoo system is on the raid0
4 device so i use an initramfs to bootup. I've been running with this
5 setup for some time, but since i migrated to baselayout2+openrc i
6 didn't understand why i need /etc/init.d/lvm to start at boot as i
7 have no lvm setup. Today i was doing some research and some questions
8 appeared:
10 * Every where says i need "<*> RAID support -> <* > RAID-0
11 (striping) mode" in kernel for fakeraid to work, but my system still
12 boots while disabling those options, are they really needed? i don't
13 understand why it is supposed to be needed. (Is it only for mdadm
14 usage?)
16 * Is "SCSI device support -> <*> RAID Transport Class" option needed?
17 What is supposed to do? I think raid features are provided by jmicron
18 driver and kernel understaands how RAID works due to "Multiple devices
19 driver support (RAID and LVM) -> <*> Device mapper support ", isn't
20 it?
22 * Last question is, after migrating to openrc i noticed that lvm2
23 package provides device-mapper tools to manage the array, but i do not
24 want /etc/init.d/lvm to start at boot as i do not use any lvm setup, i
25 just would like to get /dev/mapper/ correctly populated using
26 something like dmraid -ay. I've tried removing lvm from boot and
27 adding device-mapper instead but /dev/mapper is not populated. How
28 should i proceed to get rid of lvm script and /dev/mapper populated,
29 do i need /etc/dmtab to work? Then why would one want to use mdadm
30 instead of device-mapper, which are the advatges/disadvantages on each
31 other? i know mdadm needs an optional /etc/mdadm.conf file to work,
32 and using mdadm one could stop/start the array, add more disks to the
33 array etc But do mdadm need a boot up script to work?
35 As you can see i'm a bit confused about what's best/suits best mdadm
36 or device-mapper and why are those kernel settings needed. Thanks a
37 lot in advanced :)


Subject Author
[gentoo-user] Re: Fakeraid + lvm + openrc questions Pau Peris <sibok1981@×××××.com>