Ubuntu show wrong disk sizes, how to solve it?
Solution 1
It looks like that you have made raid1 (mirror) between partitions on your SSD and HDD. This is not best practice, since it more or less restricts performance to that of the slowest disk.
You can see that /boot
, /
and [ SWAP ]
is defined on partitions on both /dev/sda
and /dev/sdb
.
sdb 8:16 1 238.4G 0 disk
├─sdb2 8:18 1 512M 0 part
│ └─md1 9:1 0 511.4M 0 raid1 /boot
├─sdb3 8:19 1 229.9G 0 part
│ └─md2 9:2 0 229.8G 0 raid1 /
└─sdb1 8:17 1 8G 0 part
└─md0 9:0 0 8G 0 raid1 [SWAP]
sda 8:0 1 2.7T 0 disk
├─sda2 8:2 1 512M 0 part
│ └─md1 9:1 0 511.4M 0 raid1 /boot
├─sda3 8:3 1 229.9G 0 part
│ └─md2 9:2 0 229.8G 0 raid1 /
└─sda1 8:1 1 8G 0 part
└─md0 9:0 0 8G 0 raid1 [SWAP]
I would recommend that you reinstall Ubuntu using only SSD for /boot
, /
and SWAP
. If you really want a raid1/mirror setup, you should buy one more 240 GB SSD, so you mirror between similar type and size disks.
Anyway, if you take a look at your disks with gparted
(or fdisk -l
) you should see a huge unallocated amount of data on /dev/sda
.
Solution 2
The reason why your "3,0 TB" drive (sda) shows up as 2.7T is most likely due to different units being used.
The size is probably about 2.7 Tebibyte, which is approximately the same as 3.0 TB.
You can read about it here: https://en.wikipedia.org/wiki/Tebibyte
Solution 3
lsblk
shows all disk partitions, while df -lh
only shows your mounted partitions.
Lex Thoonen
Updated on September 18, 2022Comments
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Lex Thoonen over 1 year
I have a server with these characteristics:
CPU: Intel Core i7-2600
PLUSRAID Controller 4-Port SATA PCI-E - Adaptec 5405
One each, SATA SSD, 240 GB
Two each, SATA HDDs, 3.0 TB Enterprise
Two each, 8 GB DDR3 RAMI installed Ubuntu on it, but it shows the space such as this, far less than the true capacity:
root@ns1 /boot # lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sdb 8:16 1 238.4G 0 disk ├─sdb2 8:18 1 512M 0 part │ └─md1 9:1 0 511.4M 0 raid1 /boot ├─sdb3 8:19 1 229.9G 0 part │ └─md2 9:2 0 229.8G 0 raid1 / └─sdb1 8:17 1 8G 0 part └─md0 9:0 0 8G 0 raid1 [SWAP] sda 8:0 1 2.7T 0 disk ├─sda2 8:2 1 512M 0 part │ └─md1 9:1 0 511.4M 0 raid1 /boot ├─sda3 8:3 1 229.9G 0 part │ └─md2 9:2 0 229.8G 0 raid1 / └─sda1 8:1 1 8G 0 part └─md0 9:0 0 8G 0 raid1 [SWAP]
and
root@ns1 /boot # df -lh Filesystem Size Used Avail Use% Mounted on udev 7.8G 0 7.8G 0% /dev tmpfs 1.6G 5.3M 1.6G 1% /run /dev/md2 226G 17G 198G 8% / tmpfs 7.8G 0 7.8G 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock tmpfs 7.8G 0 7.8G 0% /sys/fs/cgroup /dev/md1 488M 176M 287M 38% /boot tmpfs 1.6G 0 1.6G 0% /run/user/0
I don't seem to be using all the space available on the sda disk at all, the two 3 terabytes disks.
What am I doing wrong?
Thanks!
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Lex Thoonen almost 5 yearsThank you, but still, it seems like this I only have access to 230 GB, it would be nice if I could use the 2.7 TB
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Terrance almost 5 years@LexThoonen You do have access to 240GB. Run
dmesg | grep blocks
in a terminal and you will see something like[ 3.989812] sd 4:0:0:0: [sde] 468862128 512-byte logical blocks: (240 GB/224 GiB)
which shows that you are seeing theGiB
of the drive and not theGB
. The 3TB drive shows up like[ 3.462108] sd 10:0:0:0: [sdb] 732566645 4096-byte logical blocks: (3.00 TB/2.73 TiB)
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Soren A almost 5 yearsDon't do that .. sda2 seems to be a part of a raid1 (mirror) ...
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BeastOfCaerbannog almost 5 yearsYou are right. I removed the example.
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Richie Frame almost 5 yearsIt also looks like sda is a hardware raid mirror, in addition to THAT being a mirror of sdb.