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I have created a Logical vol and used luks to encrypt it. But while rebooting the server. I get a error message (below), therefore I would have to enter the root pass and disable the /etc/fstab entry. So mount of the LUKS partition is not persistent during reboot using LUKS. I have this setup on RHEL6 and wondering what i could be missing. I want to the LV to get be mount on reboot. Later I would want to replace it with UUID instead of the device name.

Error message on reboot: "Give root password for maintenance (or type Control-D to continue):"

Here are the steps from the beginning:

[root@rhel6 ~]# pvcreate /dev/sdb 
  Physical volume "/dev/sdb" successfully created
[root@rhel6 ~]# vgcreate vg01 /dev/sdb 
  Volume group "vg01" successfully created
[root@rhel6 ~]# lvcreate --size 500M -n lvol1 vg01
  Logical volume "lvol1" created
[root@rhel6 ~]# lvdisplay 
  --- Logical volume ---
  LV Name                /dev/vg01/lvol1
  VG Name                vg01
  LV UUID                nX9DDe-ctqG-XCgO-2wcx-ddy4-i91Y-rZ5u91
  LV Write Access        read/write
  LV Status              available
  # open                 0
  LV Size                500.00 MiB
  Current LE             125
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:0

[root@rhel6 ~]# cryptsetup luksFormat /dev/vg01/lvol1 

This will overwrite data on /dev/vg01/lvol1 irrevocably.

Are you sure? (Type uppercase yes): YES
Enter LUKS passphrase: 
Verify passphrase: 

[root@rhel6 ~]# mkdir /house

[root@rhel6 ~]# cryptsetup luksOpen /dev/vg01/lvol1 house
Enter passphrase for /dev/vg01/lvol1: 

[root@rhel6 ~]# mkfs.ext4 /dev/mapper/house 
mke2fs 1.41.12 (17-May-2010)
Filesystem label=
OS type: Linux
Block size=1024 (log=0)
Fragment size=1024 (log=0)
Stride=0 blocks, Stripe width=0 blocks
127512 inodes, 509952 blocks
25497 blocks (5.00%) reserved for the super user
First data block=1
Maximum filesystem blocks=67633152
63 block groups
8192 blocks per group, 8192 fragments per group
2024 inodes per group
Superblock backups stored on blocks: 
    8193, 24577, 40961, 57345, 73729, 204801, 221185, 401409

Writing inode tables: done                            
Creating journal (8192 blocks): done
Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 21 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.

[root@rhel6 ~]# mount -t ext4 /dev/mapper/house /house

PS: HERE I have successfully mounted:
[root@rhel6 ~]# ls /house/

[root@rhel6 ~]# vim /etc/fstab  -> as follow
/dev/mapper/house /house ext4 defaults 1 2

[root@rhel6 ~]# vim /etc/crypttab -> entry as follows
house /dev/vg01/lvol1 password

[root@rhel6 ~]# mount -o remount /house
[root@rhel6 ~]# ls /house/
[root@rhel6 ~]# umount /house/
[root@rhel6 ~]# mount -a  -> SUCCESSFUL AGAIN
[root@rhel6 ~]# ls /house/

Please let me know if I am missing anything here.

Thanks in advance.

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Is your oot filesystem already encryped? You didn't actually put yor password in the crypttab did you? – Zoredache May 30 '12 at 18:41
My boot partition or any other partitions are NOT encrypted. Yes - I have put the password in /etc/crypttab file as the third string. Is thr something i am missing ? – linxsaga May 30 '12 at 18:59
Well what is the point of encypting anything if you leave the key unencrypted on the filesystem? Seems like a completely pointless thing to do. What are you protecting against? – Zoredache May 30 '12 at 19:32
Either way even if you would rand string in a file it requires to be kept unencrypted. – linxsaga May 30 '12 at 19:40
are their better alternatives ? I know we could used a rand string in a file and which could be used as a password, still the file would be protected by permissions only. But the issue here is why I cant reboot ? – linxsaga May 30 '12 at 19:43

Here is the solution i found and i am just sharing it for the benefit others.

Just typing the password in the /etc/crypttab does not work for me - Instead I created a random key which was used to encrypt the password with the following commands - However, the key is still still stored insecurely under /root/pass.key.

dd if=/dev/random of=/root/pass.key bs=32 count=1

cryptsetup luksAddKey /dev/vg01/lvol1 /root/pass.key

Then i use vim to edit /etc/crypttab and added the path of the key file.

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