81 lines
1.8 KiB
Markdown
81 lines
1.8 KiB
Markdown
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# The `usermod` command
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The `usermod` command lets you change the properties of a user in Linux through the command line. After creating a user we sometimes have to change their attributes, like their password or login directory etc. So in order to do that we use the `usermod` command.
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### Syntax:
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```
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usermod [options] USER
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```
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#### Note : Only superuser (root) is allowed to execute `usermod` command
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### Options and their Functionalities:
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|**Option** |**Description** |
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|:---|:---|
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|`-a`|to add anyone of the group to a secondary group|
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|`-c`|to add comment field for the useraccount|
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|`-d`|to modify the directory for any existing user account|
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|`-g`|change the primary group for a User|
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|`-G`|to add supplementary groups|
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|`-l`|to change existing user login name|
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|`-L`|to lock system user account|
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|`-m`|to move the contents of the home directory from existing home dir to new dir|
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|`-p`|to create an un-encrypted password|
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|`-s`|to create a specified shell for new accounts|
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|`-u`|to assigned UID for the user account|
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|`-U`|to unlock any locked user|
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### Examples:
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1. To add a comment/description for a user:
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```
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sudo usermod -c "This is test user" test_user
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```
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2. To change the home directory of a user:
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```
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sudo usermod -d /home/sam test_user
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```
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3. To change the expiry date of a user:
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```
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sudo usermod -e 2021-10-05 test_user
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```
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4. To change the group of a user:
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```
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sudo usermod -g sam test_user
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```
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5. To change user login name:
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```
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sudo usermod -l test_account test_user
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```
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6. To lock a user:
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```
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sudo usermod -L test_user
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```
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7. To unlock a user:
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```
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sudo usermod -U test_user
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```
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8. To set an unencrypted password for the user:
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```
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sudo usermod -p test_password test_user
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```
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9. To create a shell for the user:
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```
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sudo usermod -s /bin/sh test_user
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```
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10. To change the user id of a user:
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```
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sudo usermod -u 1234 test_user
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```
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