Data security > Backups > RAID >
Software >

(on Wikipedia)
http://evms.sourceforge.net/

A disk/volume management thing, with SoftRAID and more.

Required kernel patching and I never really did figure it out.

• Enterprise Volume Management System

• LVM won out.

---

• irc://irc.freenode.net#evms

—

• 2006-09-03 – (version not recorded) on (distribution not recorded) probably PCLinuxOS

Features ∞

• The Multi-Disk (MD) plug-in for RAID provides RAID levels linear, 0, 1, 4, and 5 in software.

  • MD is one plug-in that displays as four region managers that you can choose from.
  • drive linking
    — To combine pieces of storage space together. This is apparently different from clustering

• Snapshotting

  • Snapshot a working filesystem.
    — Snapshotting allows you to, for example, keep a volume online while a backup is created. Snapshots can be reinitialized or rolled back

2006-09-03 – (version not recorded) ∞

I played with EVMS to try to get RAID-1 working, but I couldn’t figure it out. I think that perhaps PCLinuxOS doesn’t have the appropriate module to do that.

Under PCLinuxOS do:

apt-get install evms evms-gui

and then you can run

evmsgui

What I did to install:

pvcreate /dev/sdc
pvcreate /dev/sdd
vgcreate vg1 /dev/sdc /dev/sdd
vgdisplay

evms_activate

.. shit.. I have no idea.

Notes ∞

(source not recorded)

I ended up doing it the long way and then using EVMS to verify the set up. In my case, I have 3 drives, 1 PATA, which I have holding my OS’s, swap, /var and /tmp files and then 2 SATA drives that I wanted as a striped LVM for /home. What I did is as follows.

I don’t know if this is the best or correct way as I am learning as I go..so, anyone reading, please feel free to correct.

First I created the Physical volumes for each of the 2 drives that will be in the group

[root@localhost ~]# pvcreate /dev/sda
Physical volume "/dev/sda" successfully created

[root@localhost ~]# pvcreate /dev/sdb
Physical volume "/dev/sdb" successfully created

Then I created the volume group:

[root@localhost ~]# vgcreate vg1 /dev/sda /dev/sdb

Then I verified the group was correct:

[root@localhost ~]# vgdisplay
--- Volume group ---
VG Name vg1
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 1
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 0
Open LV 0
Max PV 0
Cur PV 2
Act PV 2
VG Size 466.64 GB
PE Size 4.00 MB
Total PE 119461
Alloc PE / Size 0 / 0
Free PE / Size 119461 / 466.64 GB
VG UUID RTle7G-D4fp-iTiB-gxWL-hQTN-

Then I created the striped 2 drive volume for the whole drive which i called home1 in volume group 1. I have 2 250g drives from different manuf. that are a slightly different size, but it seemed to work fine

[root@localhost ~]# lvcreate -i2 -I4 -L465.7G -nhome1 vg1
Rounding up size to full physical extent 465.70 GB
Logical volume "home1" created

Then I used diskdrake to format, set mount points and write fstab for the new device

and finished with the following:

[root@localhost ]# pvdisplay
--- Physical volume ---
PV Name /dev/sda
VG Name vg1
PV Size 233.76 GB / not usable 0
Allocatable yes
PE Size (KByte) 4096
Total PE 59842
Free PE 232
Allocated PE 59610
PV UUID 6aAn7B-JvME-fT6F-Wobl-o51x-Ug6F-MxKZm3

--- Physical volume ---
PV Name /dev/sdb
VG Name vg1
PV Size 232.88 GB / not usable 0
Allocatable yes
PE Size (KByte) 4096
Total PE 59617
Free PE 7
Allocated PE 59610
PV UUID hTfpEX-Kfaw-Bgvr-xPgj-dnSU-PmGh-PQjbU5

[root@localhost ]# vgdisplay
--- Volume group ---
VG Name vg1
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 6
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 1
Open LV 1
Max PV 0
Cur PV 2
Act PV 2
VG Size 466.64 GB
PE Size 4.00 MB
Total PE 119459
Alloc PE / Size 119220 / 465.70 GB
Free PE / Size 239 / 956.00 MB
VG UUID X2N7mG-U1Hl-jJvb-83Pt-rwmG-oAKl-T6abAj

[root@localhost ]# lvdisplay
--- Logical volume ---
LV Name /dev/vg1/home1
VG Name vg1
LV UUID oj5xDH-DIJC-cU4K-Elxx-f8TP-k1Fl-EEVqpV
LV Write Access read/write
LV Status available
# open 1
LV Size 465.70 GB
Current LE 119220
Segments 1
Allocation inherit
Read ahead sectors 0
Block device 253:0

[root@localhost ]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/hda3
20G 2.4G 17G 13% /

/dev/mapper/vg1-home1
 459G 132M 459G 1% /home

/dev/hda5
5.1G 41M 5.0G 1% /tmp

/dev/hda8
13G 1002M 12G 9% /var

/dev/hdc
680M 680M 0 100% /mnt/cdrom

/dev/hda6
77G 12G 65G 15% /mnt/win_e

/dev/hda1
21G 9.2G 11G 46% /mnt/win_c

/dev/hda2
51G 33G 18G 65% /mnt/win_d

Followup ∞

FWIW, I had to reinstall PCLinuxOS and was concerned about loosing the LVM. Thankfully, upon clean install, the vg group shows up in diskdrake during install and It was as simple as selecting it as home..with Format OFF ;)

All installed and running again with lvm intact. I decided to simplify my install…just using swap and root for PATA drive and the 2 SATAs as striped lvm /home I still have 90g or so on the PATA drive I have yet to partition…still not sure what I am going to do with it =p

[root@localhost ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/hda5              97G  2.1G   90G   3% /
/dev/mapper/vg1-home1
                      459G   35G  425G   8% /home
none                 1014M  3.4M 1011M   1% /tmp