[ale] Mission accomplished - LUKS & LVM

[Scott Castaline]

Original setup at time of Fedora 12 install:

sda WD 500GB
2 partitions sda1 /boot 300MB
	     sda2 VG01 LUKS
sdb Seagate 500GB
1 partition  sdb1 VG02 LUKS

sdc Seagate 500GB
1 partition  sdc1 VG03 LUKS

sdd Seagate 500GB
1 partition  sdd1 formatted as ext4 backup

VG01 8 LVs formatted as ext4
      1 LV  formatted as swap labelled swap01 LUKS
VG02 2 LVs formatted as ext4
      1 LV  formatted as swap labelled swap02 LUKS
VG03 1 LV  formatted as ext4

I wanted to replace VG03 with a 1TB and later combine the replaced 500GB 
with VG02. I had to first remove the drive from LVM with lvremove, 
vgremove, and pvremove. Then I did the following:

1.  Used fdisk to create 1 partition using the full hdd on /dev/sdd
2.  cryptsetup -c aes-xts-plain -s 512 luksFormat /dev/sdd1
3.  cryptsetup luksUUID /dev/sdd1 to retrieve the UUID assigned by LUKS
4.  cryptsetup luksOpen /dev/sdd1 luks-<the UUID retrieved in 3>
     Enter LUKS passphrase for /dev/sdd1:
     key slot 0 unlocked
     Command succesfull
5.  Edited /etc/crypttab adding: luks-<the UUID retrieved in 3>
     UUID=<the UUID retrieved in 3> none
6.  By either using dmsetup ls or ls -l /dev/mapper to find the minor
     number assigned to the new luks volume
7.  pvcreate /dev/dm-? (use the minor number assigned) (pvscan to
     verify)
8.  vgcreate Name-Of-VG /dev/sdd1  (vgscan to verify)
9.  lvcreate -n Name-Of-LV -L 931G Name-Of-VG  I used all free space
     which you can get from the output of pvscan.
10. mkfs.ext4 /dev/mapper/VGname-LVname
11. tune2fs -o user_xattr,acl -i 0 -c -1 /dev/mapper/VGname-LVname
     This is to use the same options as used in rest of Fedora12
12. cryptsetup luksClose luks-UUID  this is where I started having
     trouble as it came back as device was busy and I could not find
     out why.
13. Add LV to fstab and reboot

It came up fine and I was able to access the new drive fine, but there 
are some minor issues.

1. On boot it used to repeat "key slot 0 unlocked" 5 times, once for 
each LUKS-Volume (each of the 3 VGs and the 2 swap LVs). It now repeats 
7 times. I understand the 6 times because I do have the original VG03 
hooked up as sdc and though it is removed from LVM it's still a LUKS 
volume, but now where does the 7th one come from? Anyone know if I 
missed something on the removal of the drive?

2. I also noticed 5 entries in crypttab. I can verify 4 of them with 
cryptsetup luksUUID /dev/sd? but not the extra 1. Anyone know of a way 
to go the other way by entering the UUID would output the physical device?

3. I have noticed that this wound up creating a total of 18 units, 
devices or what ever as I now have dm-0 thru dm-17. dm-0 thru dm-3 
relate to the sda, sdb, sdc, & sdd. Also dm-4 thru dm-12 relate to the 
LVs on sda2, dm-13 relates to the LV on sdd1 and dm-14 thru dm-16 relate 
to the LVs on sdb1, but dm-17 points to dm-16, which points to dm-0 
which is sdb1???? I don't get it.

Stay tuned for further misadventures of the blown up seagate, in the 
meantime can anyone enlighten me on the 3 problems?