Difference between revisions of "Weasel disk partition plan"
(→The big plan) |
(→The big plan) |
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ACTIVE '/dev/Ubuntu/swap_1' [5.88 GB] inherit | ACTIVE '/dev/Ubuntu/swap_1' [5.88 GB] inherit | ||
| − | + | ====bring sdc and sdd online==== | |
| − | + | ====create volume group netstore on sdc==== | |
pvcreate /dev/sdc | pvcreate /dev/sdc | ||
vgcreate netstore /dev/sdc | vgcreate netstore /dev/sdc | ||
mkfs -t ext3 /dev/netstore/netstore | mkfs -t ext3 /dev/netstore/netstore | ||
| − | + | ====create volume group netback on sdd==== | |
pvcreate /dev/sdd | pvcreate /dev/sdd | ||
vgcreate netback /dev/sdd | vgcreate netback /dev/sdd | ||
| − | + | ====move big from sdb to sdc==== | |
mount /dev/netstore/netstore /big2 | mount /dev/netstore/netstore /big2 | ||
rsync -av /big/share /big2 | rsync -av /big/share /big2 | ||
| Line 120: | Line 120: | ||
cd /dev/disk/by-uuid | cd /dev/disk/by-uuid | ||
ln -s ../../mapper/netstore-netstore 91fdcaaa-1ff7-4644-9976-10bda5f4919e | ln -s ../../mapper/netstore-netstore 91fdcaaa-1ff7-4644-9976-10bda5f4919e | ||
| − | + | edit /etc/fstab to associate /big with the UUID for netstore | |
umount /big2 | umount /big2 | ||
umount /big | umount /big | ||
mount /big | mount /big | ||
| − | + | ====create logical volumes for var, home, store on volume group Ubuntu==== | |
| − | + | ====move those directories from root and mount them==== | |
| − | + | ====leave unassigned space on volume group Ubuntu so I can grow any of those logical volumes==== | |
When done, lvscan should look like this: | When done, lvscan should look like this: | ||
Revision as of 23:31, 26 June 2008
Currently I have two partitions, root and big. They are both managed by lvm and look like this:
root@weasel:/boot# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/Ubuntu-root
224G 107G 106G 51% /
/dev/mapper/vg00-big 230G 187G 32G 86% /big
It would be much more reasonable to have a small root partition that is easily backed up and separate partitions for /home, /store, and /big.
/store is a shared network-accessible space. /big is used for automatic backups of root, /home, and /store.
| Partition | Size |
|---|---|
| root | 4G |
| store | 99G |
| home | 3.4G |
| var | 1.2G |
| big | 187G |
| Total | 300G |
root is 107G (root + home + var + store), so if I would split them apart, root could be as small as 4G.
It would be handy if the root partition could be kept small enough to be backed up on a DVD.
So the new scheme would have 4 physical volumes:
| Device | Size | Use |
|---|---|---|
| /dev/hda | 250G | root, store, home, var |
| /dev/hdb | 250G | backup root, store, home, var |
| /dev/hdc | 500G | big |
| /dev/hdd | 500G | big, network backup |
The main idea is to partition disk failures, so I don't want to bunch all the disks together into a single volume group. When one disk goes bad, I don't want to lose access to part of another disk just because it is in the same volume group. I'm assuming that a volume group will fail when any physical volume in that group fails.
The logical volumes should be divided into primary and backup volumes and the sizes of the two volumes should match.
There should be a primary root, store, home, var, big. And there should be an equivalent backup root, store, home, var, big.
There should also be sufficient unformatted space in the primary volume group for a snapshot of the root partition so that an image can be taken and stored offline. But if root is small, that shouldn't be a problem.
So I'll need to move big (sdb1 vg00) to a 500G drive.
Contents
- 1 The big plan
- 1.1 bring sdc and sdd online
- 1.2 create volume group netstore on sdc
- 1.3 create volume group netback on sdd
- 1.4 move big from sdb to sdc
- 1.5 create logical volumes for var, home, store on volume group Ubuntu
- 1.6 move those directories from root and mount them
- 1.7 leave unassigned space on volume group Ubuntu so I can grow any of those logical volumes
The big plan
| Physical volumes | sda (250G) | sdb (250G) | sdc (500G) | sdd (500G) |
|---|---|---|---|---|
| Volume groups | Ubuntu | netstore | netback | |
| Logical volumes | root,var,home,store,swap | netstore | netback | |
| Percent free | 57% | 57% | 62% | 62% |
Currently lvscan looks like this:
ACTIVE '/dev/vg00/big' [232.88 GB] inherit ACTIVE '/dev/Ubuntu/root' [226.77 GB] inherit ACTIVE '/dev/Ubuntu/swap_1' [5.88 GB] inherit
bring sdc and sdd online
create volume group netstore on sdc
pvcreate /dev/sdc vgcreate netstore /dev/sdc mkfs -t ext3 /dev/netstore/netstore
create volume group netback on sdd
pvcreate /dev/sdd vgcreate netback /dev/sdd
move big from sdb to sdc
mount /dev/netstore/netstore /big2 rsync -av /big/share /big2 rsync -av /big/weasel /big2 vol_id -u /dev/netstore/netstore cd /dev/disk/by-uuid ln -s ../../mapper/netstore-netstore 91fdcaaa-1ff7-4644-9976-10bda5f4919e
edit /etc/fstab to associate /big with the UUID for netstore
umount /big2 umount /big mount /big
create logical volumes for var, home, store on volume group Ubuntu
move those directories from root and mount them
leave unassigned space on volume group Ubuntu so I can grow any of those logical volumes
When done, lvscan should look like this:
/dev/Ubuntu/root /dev/Ubuntu/swap_1 /dev/Ubuntu/var /dev/Ubuntu/home /dev/Ubuntu/store /dev/rootback/rootback /dev/netstore/netstore /dev/netback/netback
