3.0 KiB
FDisk Basics
sudo fdisk /dev/sda
-
m for help.
-
n to make a partition.
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t to mark the partition type (see IDs below).
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w to write the changes to the disk.
Note the asterisk marking the boot partition.
IDs
| ID | Meaning |
|---|---|
| 83 | Linux |
| 5 | Extended |
| 82 | Swap |
fdisk will not help with a GPT formatted drive. For this, use gdisk, which is mostly the same.
Now that we have a partition, we can make it into a filesystem. Most will use:
sudo mkfs -t ext4 /dev/sdc1
or if you're making a swap partition, you can use:
sudo mkswap /dev/sdb2
or for the reiser filesystem, we can use:
sudo mkreiserfs /dev/sdc2
File System Types
| Type | Advantages | Disadvantages |
|---|---|---|
| ext2 | No journaling means that the file offers no crash recovery. | |
| ext3 | Journaling | |
| ext4 | Journaling and handles files of up to 16TB. | |
| reiserfs | Journalin and stable. | |
| btrfs | Reliable and stable | |
| XFS | Journaling, great for large files. | |
| VFAT | Comptable with Windows, like FAT32 |
Parted
sudo parted /dev/sdb
Monitoring
Look at physical and virtual partitions:
df -h
or divide things by inode - the thing which records where files are?
df -i
Examine a filesystem with:
sudo dumpe2fs /dev/sda1 | less
Prevention
There are multiple programs which work mostly the same way.
sudo tune2fs -c 30 /dev/sda1
This will check sda1 every 30 boots. It can also be checked every month.
sudo tune2fs -i 1m /dev/sda1
This thing can also make a new label for the system:
sudo tune2fs -L new_name /dev/sdb3
Repair
Start by unmounting the filesystem.
sudo umount /dev/sdc1
Then it's time to check.
sudo fsck /dev/sdc1
And possibly repair damage:
e2fsck -p /dev/sdc1
or the same with:
sudo debugfs /dev/sdc1
Mounting
You can mount with a specified filetype with:
sudo mount -t ext3 /dev/sdc2 /mnt/stick
or if you don't know the type, just try the lot:
sudo mount -a /dev/sdc1 /mnt/stick
File Systems
xfs and zfs can only be expanded.
Shrink Filesystem
NB: When I followed these instructions, the process destroyed my data. Seemed fine on the YouTube video.
Check the filesystem's health:
sudo e2fsck -f /dev/sdb1
Resize the file system to something smaller than what you want, so here I want 500G and so I resize to 450 G.
resize2fs /dev/sdb1 450G
Then delete the partition with either gdisk or fdisk, depending upon the layout.
sudo fdisk /dev/sdb
d
Then make a new filesystem of the desired type with:
n
And finally resize to the full size you want:
sudo resize2fs /dev/sdb1
And then check your disk again with e2fsck.
(The e2fsck saved my disk in the end, YMMV)
Logical Volume
Let's start with names. PV = 'Physical Volume', VG = 'Volume Group', and LV = 'Logical Volume'.
Now we can create a volume group out of sdb2 and sdc3:
sudo vgcreate my-new-vg /dev/sdb2 /dev/sdc3
Then make a new logical volume out of the volume group:
sudo lvcreate -n my-new-lv my-new-vg
Then have a look at all logical volumes:
sudo lvscan