Help with a backup solution

[MegaMan1122]

Hi all,

I have an idea for a backup solution, just like to see if it would actually work
Note: I'm looking for a non raid solution at the moment

Ideally I'd like to use my 2nd HDD as a full drive backup in case the 1st HDD dies. Then the 2nd one can replace the 1st.

So I was thinking if I first do a full drive clone to my 2nd HDD, then use rsync to keep it updated.

my 1st drive looks like this

/dev/sda5 7.8G 917M 6.5G 13% /
/dev/sda8 645G 1.4G 611G 1% /home
/dev/sda6 996M 35M 910M 4% /tmp
/dev/sda3 7.8G 3.9G 3.6G 52% /usr
/dev/sda2 9.7G 431M 8.8G 5% /var
/dev/sda1 122M 18M 98M 16% /boot
tmpfs 1.9G 0 1.9G 0% /dev/shm

If I have cloned the 2nd hdd, could I then mount each partition under say /backup. eg

/dev/sdb8 --> /backup/home
/dev/sdb6 --> /backup/tmp
/dev/sdb3 --> /backup/usr
etc......

If the main HDD ever dies then I could replace HDD2 with HDD1 and mount them as expected

/dev/sda8 --> /home
/dev/sda6 --> /tmp
/dev/sda3 --> /usr
etc.....

Would this actually work?

Thank you

[RDU]

Should work, I already cloned a disk using rsync (and rebuilding bootloader).
The best way to know is to try to boot your second disk.

[Irithori]

Also, have a look at /etc/fstab.
You will most likely have to modify it beforehand or from a liveCD, if you really want to boot from the second harddisc.

[RDU]

In the described scenario (disk 1 failed and removed), the second disk will be the 1st, so it should be sda again and no changed needed. Also modern distro use LABEL in fstab.

[Irithori]

..and labels would fail
Either you give the same label to the corresponding partitions, which results in conflicts.
Or the second harddisc has none (or other) labels, then fstab needs to be edited.

[RDU]

You're right, label have to be removed from fstab. But then no edit is needed in case of 1st disk broken as the 2nd disk will be the 1st and seen as sda

[MegaMan1122]

I have my current fstab file below, what changes if any would I need to make on the 2nd HDD /etc/fstab so it would boot?

LABEL=/                 /                       ext3    noatime,defaults,usrquota        1 1
LABEL=/home             /home                   ext3    noatime,defaults,usrquota        1 2
LABEL=/backup           /backup                 ext3    noatime,defaults        1 2
LABEL=/tmp              /tmp                    ext3    noatime,defaults        1 2
LABEL=/usr              /usr                    ext3    noatime,defaults,usrquota        1 2
LABEL=/var              /var                    ext3    noatime,defaults,usrquota        1 2
LABEL=/boot             /boot                   ext3    noatime,defaults        1 2
tmpfs                   /dev/shm                tmpfs   defaults        0 0
devpts                  /dev/pts                devpts  gid=5,mode=620  0 0
sysfs                   /sys                    sysfs   defaults        0 0
proc                    /proc                   proc    defaults        0 0
LABEL=SWAP-sda7         swap                    swap    defaults        0 0

Thank you

[MegaMan1122]

I did a little test in a VM, I cloned HDD1 to HDD2, I didnt mount the 2nd drive, but when I tried to restart the machine it failed. It would only boot once I deleted the contents of HDD2. Hmmmm

[RDU]

I would check changing the label based fstab by a device based fstab (using /dev/sda1, ... instead of LABEL=/xxxx

[MegaMan1122]

Ill try that in my VM and report back the results. Thanks!