Linux
SSH
| Description | Command |
|---|---|
| Create private/public SSH key file using 2048 bit encryption and with a comment. The command creates files under ~/.ssh folder. | ssh-keygen -b 2048 -C user@host.domain
|
| Push public SSH key to a server | ssh-copy-id -p 41111 -i ~/.ssh/id_rsa.pub mhan@remote.server.com
|
| Reset (SELinux) permissions related to SSH. This may be needed if all else fails to correct the issue of system not accepting public keys. | restorecon -R -v ~/.ssh
|
Disk
LVM
Physical volume
| Description | Command |
|---|---|
| Initialize for use as LVM physical volume. | pvcreate /dev/sdb1
|
| Scanning for block devices. | lvmdiskscan
|
| Display the physical volumes. | pvdisplay
|
| Show all physical devices. | pvscan
|
| Prevent allocation of physical extents on the free space of one or more physical volumes. | pvchange -x n /dev/sdb1
|
| Resize. | pvresize
|
| Remove LVM label. | pvremove
|
Volume group
| Description | Command |
|---|---|
| Create a volume group. | vgcreate vg1 /dev/sdb1 /dev/sdc1
|
| Add a physical volume to a volume group. | vgextend vg1 /dev/sdd1
|
| Display volume group. | vgdisplay new_vg
|
| Scan disks for volume groups. | vgscan
|
| Remove a physical volume from a volume group. | vgreduce group_name /dev/sdc1
|
| Change the maximum number of logical volumes of volume group vg00 to 128. | vgchange -l 128 /dev/vg00
|
| Activate or deactivate a volume group. | vgchange -a n my_volume_group
|
| Remove a volume group. | vgremove officevg
|
| Split the physical volumes of a volume group and create a new volume group. | $ vgsplit bigvg smallvg /dev/ram15
|
| Merge the inactive volume group my_vg into the active or inactive volume group databases giving verbose runtime information. | vgmerge -v databases my_vg
|
| Change the name of a volume group. | vgrename vg02 my_volume_group
|
File
Permissions
| Letter | Number |
|---|---|
| r | 4 |
| w | 2 |
| x | 1 |
| rw- | 6 |
| r-x | 5 |
| rwx | 7 |