Category: PC Hardware

It is simple, here is what you need to know

You can format it EXT4, but ext2 and ext3 are also OK ! ext2 and ext3 allow up to 16TB disks, and file sizes of up to 2TB, ext4 allows much more.

Any linux kernel newer than 2.6.31 should work just fine with “Advanced format” drives using the exact same steps in this article.

MBR only supports 2TB drives, you need GPT, so let us get started

1- apt-get update
2- apt get install parted
3- parted /dev/sdc
4- mklabel gpt
5- Answer yes to: Warning: The existing disk label on /dev/sdb will be destroyed and all data on this disk will be lost. Do you want to continue?
Yes/No? yes
6- mkpart primary ext4 0% 100% (to make a partition as big as the disk (will occupy starting from first megabyte (for alignment) to the end of disk))
7- quit

FYI, if you want multiple partitions, here are the 2 lines that should replace step 6
6- mkpart primary ext4 0% 40%
6- mkpart primary ext4 40% 100%

and remember to format both (sdc1 and sdc2) when you are done with parted

Now to formatting the drive

mkfs.ext4 /dev/sdc1

Before mounting it, i like ext4, but i don’t want a journaling OS on this drive that is not the system drive, so i will need do a few things to the drive first

Lazy writeback

tune2fs -o journal_data_writeback /dev/sdc1

No Journaling

tune2fs -O ^has_journal /dev/sdc1

Now to check what we have

dumpe2fs /dev/sdc1 |grep 'Filesystem features'

Or maybe if you want the whole thing on the screen

dumpe2fs /dev/sdc1 |more

if has_journal option exist when executing the first – you have journal on the file system

And there we are, Now we need to mount it at boot time by adding it to fstab, to do that, we will need the disk’s unique ID !

8- Now executing the following command will give you the unique ID of this new partition for use with fstab (The disk list we will edit below in step 10)
blkid /dev/sdc1
9- create the directory where you want to mount your hard disk, for example
mkdir /hds
mkdir /hds/3tb
10- Now, we add the following line to fstab, notice that noatime increases performance, but some applications might need or rely on it. postfix does not and i have verified that.

UUID=b7a491b1-a690-468f-882f-fbb4ac0a3b53       /hds/3tb            ext4     defaults,noatime                0       1

defaults and noatime are but only a couple of options, here are more options that you can add
nofail = If the disk is not present, continue booting
nobootwait = Limit the amount of time you plan to wait
noauto = Don’t mount it until I issue a “mount /dev/sdb1”, or mount “/hds/thisdisk” command

11- Now execute
mount -a

You are done,. if you execute
df -h
You should see your 2+TB hard drive in there !

To make sure the drive is aligned correctly, i like to write a file on it and see how fast that goes… so let us use a 2GB file

dd if=/dev/zero of=/hds/WD2000_3/deleteme.img bs=1M count=2000

Outcome came out (for a western digital black 2TB)
First run: 2097152000 bytes (2.1 GB) copied, 5.94739 s, 353 MB/s
Consecutive runs: 2097152000 bytes (2.1 GB) copied, 11.1405 s, 188 MB/s
Outcome came out for a western digital green 3TB
First run: 2097152000 bytes (2.1 GB) copied, 8.32337 s, 252 MB/s
Consecutive runs: 2097152000 bytes (2.1 GB) copied, 14.376 s, 146 MB/s

the consecutive runs give close results, what i printed here is the average

Section 1: My hard drive has bad sectors / Blocks / area

Do i need to change it ?
Not necessarily, but If it is in warranty, and they allow you to replace it, a new one is not a bad idea, otherwise read on

it all depends on whether the bad sectors are expanding or not, if they are not, they are probably caused by shock to the hard drive, usually, it is enough to mark them as bad using “chkdsk /r” on windows and leave the drive working.

To find out if your bad sectors are Spreading or not spreading, do a “chkdsk /r” four times, make sure the same number appears in the second and third and fourth time (Forget the first time), then, if the second is different but the third and fourth are the same, then do the test 2 more times, and make sure you get the same number of bad sectors for trials 3, 4, 5, 6, if so, your bad sectors are not spreading.

You did not mention backup in the answer before, do we need to backup ?
People would typically ask you to backup just in case, i say you should always have backup of your most important files, non spreading sectors of the hard drive, in my humble experience do not contribute negatively to reliability, so my answer is, backup should be done regardless

How do i know how many bad sectors are marked on an NTFS hard drive ?
There is a tool called nfi.exe that comes with a bundle Microsoft makes available here http://support.microsoft.com/kb/253066/en-us this tool is part of (OEM Support Tools), it can tell you everything about a disk formatted in NTFS

I accedientally pulled the power plug of a PC from the socket, and that PC was just starting to boot. The seagate hard drive inside stopped working, and the bad sectors turned out to affect the partition table, in any case, i slaved it on a windows vista PC, then into the Computer management, disk management panel, and what do you know, as if it has no paritions…

The solution to detect the boundaries of the 4 partitions it had is software called XXXX

Ran the software (The analyze option) , and what do you know, my partions exactly, 100MB made by Windows 7, a 479 GB partition for Windows, a 1GB swap partition for linux and an EXT3 partition for Linux…

So happily i asked the software to write the partitioning info to the disk, but the disk won’t hold the data, the bad sectors are where Windows writes the partition information

So, i ran down to the computer shop (In our building), and got the same exact drive (Seagate 500GB Model number xxx)

Mounted both on a Linux machine as slaves, both the damaged and the target.

To find out which one is SDC and which one is SDB, i watched as the linux machine booted, and as it booted, it threw in errors saying SDB all the time, so i know that SDB is the busted drive !

Installed gddrescue (apt-get install gddrescue), and ran it with the following command

ddrescue /dev/sdb /dev/sdc resumelog.log

(The additional log file helps us resume in case of interruption)

Once that is done, i put the new hard drive in a Windows machine, still can not see any partition info

1- Ran xxxx, it can see the 4 partitions, write changes… and what do you know, the partitions stick, we are good to go, i restart, but still, Windows can now see the partitions, but thinks drive G is not formated !

So i opened the command prompt (Elevated), then ran the command

chkdsk g: /f

the /f stands for fix, the thing took some time, but after the restart drive G works fine, all files are in there, and no one wants to kill me no more 🙂

The results of the commands on this post are Here

On windows, You can use speedfan, under linux you can read the smart data as follows

Use the smartctl command, but first you must install the package

apt-get install smartmontools

1- Checking for smart support, (All recent hard drives have it but you need to enable it in BIOS)

smartctl -i /dev/sdb

2- Enable reading it

smartctl -s on -d ata /dev/sdb

See it

smartctl -d ata -H /dev/sdb

Read more

smartctl -d ata -a /dev/sdb

Now some manufacturer specific smart atributes exist, you need to google them out, Also smart is not definitive, if S.M.A.R.T data says ok but there is a ticking noise in your hard drive, Don’t trust the hardware data, get backup.

Some hard drives like the Samsung Spinpoint come with extensive diagnostics software, My 3 2.5′ disks pass the test, pass the smart test, and tick when warm, i will let you know if it was the tick of death sometime soon

To run a self test… (captive mode, disk dedicated to test), -C makes it run in captive mode

smartctl -t <short|long|conveyance|select> -C /dev/sdb

And in offline mode (Background, does not block drive)

smartctl -t <short|long|conveyance|select> /dev/sdb