Linux: Difference between revisions
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| style="width: 50%;" | Create private/public SSH key file using 2048 bit encryption and with a comment. The command creates files under ~/.ssh folder. | | style="width: 50%;" | Create private/public SSH key file using 2048 bit encryption and with a comment. The command creates files under ~/.ssh folder. | ||
| style="width: 50%;" | | | style="width: 50%;" class="cli" | ssh-keygen -b 2048 -C user@host.domain | ||
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| style="width: 50%;" | Push public SSH key to a server | | style="width: 50%;" | Push public SSH key to a server | ||
| style="width: 50%;" | | | style="width: 50%;" class="cli" | ssh-copy-id -p 41111 -i ~/.ssh/id_rsa.pub mhan@remote.server.com | ||
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| style="width: 50%;" | Reset (SELinux) permissions related to SSH. This may be needed if all else fails to correct the issue of system not accepting public keys. | | style="width: 50%;" | Reset (SELinux) permissions related to SSH. This may be needed if all else fails to correct the issue of system not accepting public keys. | ||
| style="width: 50%;" | | | style="width: 50%;" class="cli" | restorecon -R -v ~/.ssh | ||
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Revision as of 05:59, 3 April 2018
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 Volume group "smallvg" successfully split from "bigvg" |
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 |
Users
UID or GID
Description | Command |
---|---|
Check UID. | id -u username |
Check GID. | id -g username |
Check all of the groups a user belongs to. | id -G username |
Check UID and all of the groups a user belongs to. | id username |
File
Permissions
Letter | Number |
---|---|
r | 4 |
w | 2 |
x | 1 |
rw- | 6 |
r-x | 5 |
rwx | 7 |