Edit: It was not 4TB disk but 6TB disk in fact. (We actually ordered 4TB disk...)
I think the problem of the backup disk was the flaky power supply for the external drive.
I swapped the drive to a new HGST 4TB one, but it was neither recognized nor spun up with the external power supply we had. So I decided to put both the new and old drives in the PC chassis to power them up with the internal power supply. I tested the old disk via a USB-SATA cable. However, this disk was not recognized. I noticed that the disk was not HGST 4TB but Seagate 3TB. Is it possible? I thought it was 4TB... Did I miss something?
Once the new 4TB was connected to the USB-SATA, it was very smooth to get it mounted. Now the disk is mounted as /media/40mBackup as before. /etc/fstab was also modified with the new UUID. All the command logs are found here below.
Let's see how the morning backup goes. It would take a while to copy everything on the new disk. So it was actually very nice to set this disk up by Friday midnight.
controls@chiara|~> lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 465.8G 0 disk
---- sda1 8:1 0 446.9G 0 part /
---- sda2 8:2 0 1K 0 part
---- sda5 8:5 0 18.9G 0 part [SWAP]
sdb 8:16 0 1.8T 0 disk
---- sdb1 8:17 0 1.8T 0 part
sdc 8:32 0 3.7T 0 disk
---- sdc1 8:33 0 3.7T 0 part /home/cds
sr0 11:0 1 1024M 0 rom
sdd 8:64 0 5.5T 0 disk
controls@chiara|~> sudo mkfs -t ext4 /dev/sdd1
mke2fs 1.42 (29-Nov-2011)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
183144448 inodes, 1465130385 blocks
73256519 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4294967296
44713 block groups
32768 blocks per group, 32768 fragments per group
4096 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424, 20480000, 23887872, 71663616, 78675968,
102400000, 214990848, 512000000, 550731776, 644972544
Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
controls@chiara|~> blkid
/dev/sda1: UUID="972db769-4020-4b74-b943-9b868c26043a" TYPE="ext4"
/dev/sda5: UUID="a3f5d977-72d7-47c9-a059-38633d16413e" TYPE="swap"
/dev/sdc1: UUID="92dc7073-bf4d-4c58-8052-63129ff5755b" TYPE="ext4"
/dev/sdd1: UUID="1843f813-872b-44ff-9a4e-38b77976e8dc" TYPE="ext4"
controls@chiara|~> sudo emacs -nw /etc/fstab
controls@chiara|~> cat /etc/fstab
# /etc/fstab: static file system information.
#
# Use 'blkid -o value -s UUID' to print the universally unique identifier
# for a device; this may be used with UUID= as a more robust way to name
# devices that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type> <options> <dump> <pass>
proc /proc proc nodev,noexec,nosuid 0 0
# / was on /dev/sda1 during installation
UUID=972db769-4020-4b74-b943-9b868c26043a / ext4 errors=remount-ro 0 1
# swap was on /dev/sda5 during installation
UUID=a3f5d977-72d7-47c9-a059-38633d16413e none swap sw 0 0
#UUID="90a5c98a-22fb-4685-9c17-77ed07a5e000" /media/40mBackup ext4 defaults,relatime,commit=60 0 0
UUID="1843f813-872b-44ff-9a4e-38b77976e8dc" /media/40mBackup ext4 defaults,relatime,commit=60 0 0
#fb:/frames /frames nfs ro,bg
UUID=92dc7073-bf4d-4c58-8052-63129ff5755b /home/cds ext4 defaults,relatime,commit=60 0 0
controls@chiara|~> sudo mount -a
controls@chiara|~> df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda1 461229088 10694700 427105320 3% /
udev 15915020 12 15915008 1% /dev
tmpfs 3185412 868 3184544 1% /run
none 5120 0 5120 0% /run/lock
none 15927044 484 15926560 1% /run/shm
/dev/sdc1 3845709644 1809568856 1840789912 50% /home/cds
/dev/sdd1 5814346836 190408 5521130352 1% /media/40mBackup |