Mounting a Newly Attached Volume Manually
This is an example of how to mount (and if necessary partition) an additional disk on a Charon host system. Please refer to the Linux manual pages for details.
The general tasks on the Charon host system require to identify the disk, add a file system to it (if this has not been done before), and mount the disk on a suitable mount-point.
Step 1: Identify new disk
After logging in on the system, you can identify the new disk using the lsblk command:
# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 20G 0 disk ├─sda1 8:1 0 200M 0 part /boot/efi └─sda2 8:2 0 19,8G 0 part / sdb 8:16 0 200G 0 disk
In the example above, the new disk is /dev/sdb. The output shows no mount-point, i.e., the disk is not mounted yet. It also does not have any partitions.
Please note:
- A disk without partitions can also have a filesystem and data on it. Hence be sure that the disk really does not have any important data on it before you partition it.
- If a system has many disks, it is helpful to run the lsblk command before the new disk is added. This makes it easy to identify the new disk in the output after it has been added.
Step 2: Partition disk (fdisk or parted) - only if required
Please note: This step is only meant for new disks or to re-partition an existing disk. It will destroy all data on an existing disk.
Please refer to the manual pages ($ man parted and $ man fdisk) of your Linux distribution for details on the disk-partitioning commands. If the whole disk is used for one filesystem, it is not strictly required to create a partition. The decision of which disk layout is required depends on the customer requirements is the responsibility of the user.
After creating one partition on disk with fdisk (# fdisk /dev/sdb), the lsblk output shows the new partition:
# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 30G 0 disk ├─sda1 8:1 0 500M 0 part /boot └─sda2 8:2 0 29,5G 0 part / sdb 8:32 0 64G 0 disk └─sdb1 8:33 0 64G 0 part
Step3: Create a filesystem on the new partition(s)
Use the mkfs command to create a new filesystem. The selection of a filesystem depends on customer requirements. For example, to create an XFS filesystem, use
# mkfs.xfs /dev/sdb1
Please refer to the documentation of your Linux distribution for details about the mkfs command.
Step 4: Create a mount-point and mount the new filesystem
The following example shows how to create a mount-point and mount the file system. Please note that this is just a basic example. As the /dev/sdX device names are not guaranteed to be persistent, it is better to use names from the /dev/disk/by-* hierarchy (for example by-uuid) for permanent use.
# mkdir /space# mount /dev/sdb1 /space
The df command shows the mounted filesystem:
# df Filesystem 1K-blocks Used Available Use% Mounted on devtmpfs 4065684 0 4065684 0% /dev tmpfs 4077556 16 4077540 1% /dev/shm tmpfs 4077556 9224 4068332 1% /run tmpfs 4077556 0 4077556 0% /sys/fs/cgroup /dev/sda2 30929148 1677416 29251732 6% / /dev/sda1 508580 65512 443068 13% /boot tmpfs 815512 0 815512 0% /run/user/1000 /dev/sdb1 65923628 53272 62498580 1% /space
Step 5: Mount the disk automatically at system boot
To mount the disk automatically when the system boots, you must add it to the file /etc/fstab.
Please note: The device naming /dev/sdXN (e.g., /dev/sdb1) is not guaranteed to be persistent across reboots. Hence, it is advisable to use a persistent name from the /dev/disk/by* hierarchy (for example, the UUID).
You can use the ls or the blkid command to identify the UUID. Examples:
$ ls -l /dev/disk/by-uuid/ total 0 lrwxrwxrwx. 1 root root 10 2020-08-14 21:14 0c523909-fb78-48cb-9dc8-e7a08197a673 -> ../../dm-4 lrwxrwxrwx. 1 root root 10 2020-08-14 21:14 31fa8e8c-a6c0-45f7-9892-da13ba81e0e5 -> ../../sdb1 $ blkid |grep sdb1 /dev/sdb1: UUID="31fa8e8c-a6c0-45f7-9892-da13ba81e0e5" BLOCK_SIZE="4096" TYPE="xfs" PARTUUID="db62deaa-f25f-43d4-b958-700c1c13d844"
To add the device to /etc/fstab perform the following steps:
- As the root user, open the file /etc/fstab with a text editor.
- Add the mount command to the file. Please note: The following is for illustration only. The exact options depend on your requirements.
Sample fstab entry:UUID=31fa8e8c-a6c0-45f7-9892-da13ba81e0e5 /space xfs defaults 1 2 - Save the file.
- Test if the automatic mount works correctly.