Liven
January 1st, 2016, 07:32 AM
Commands that I use on my CentOS server
Share your useful hax/commands here! Any OS welcome!
Useful Linux Commands
Rights Management
Adds rights to all the users on the system to all the files and folders in the specified folder:
>sudo chmod -R ugo+rw /foo/bar
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Harden Linux
Disable root login:
>sudo vi /etc/ssh/sshd_config
Locate the line:
#PermitRootLogin yes
Press INSERT
Change it to:
PermitRootLogin no
Press escape, then type
>:wq
To save and quit
w: write
q: quit
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Potential Useful Commands In Emergency Crisis
Get all the users logged-in to the system:
>w
Log a user out of their session:
>pkill -KILL -u username
Changing a user(s) password
>passwd user
Modifying the sudo user(s)
>sudo visudo
Show all running processes (and who is running it)
>ps aux | less
<- and -> to scroll
And to quit:
>q
And if all else fails:
>shutdown -h now
That will shut down the system as soon as you type the command
And to prevent mishaps, please log out:
>logout
That will close the terminal and the session.
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Useful info for a server move (or just for having backups sake)
Exporting a database:
>mysqldump -p database_name > /path/to/file.sql
Importing a database:
First, we need to create the desired database we are going to import:
>CREATE DATABASE dbname
Then, do this:
>exit;
Then, we can import:
>mysql -p dbname < /path/to/file.sql
Type in the MySQL password and it will import
Create a MySQL user:
>CREATE USER 'newuser'@'localhost' IDENTIFIED BY 'password';
Then, we have to grant permissions to the user (you can set for all dbs, but i want the website to only have some permissions)
>GRANT permission ON db.table TO 'username'@'localhost';
Type of permissions that can be granted (copypasta):
ALL PRIVILEGES- as we saw previously, this would allow a MySQL user all access to a designated database (or if no database is selected, across the system)
CREATE- allows them to create new tables or databases
DROP- allows them to them to delete tables or databases
DELETE- allows them to delete rows from tables
INSERT- allows them to insert rows into tables
SELECT- allows them to use the Select command to read through databases
UPDATE- allow them to update table rows
GRANT OPTION- allows them to grant or remove other users' privileges
Share your useful hax/commands here! Any OS welcome!
Useful Linux Commands
Rights Management
Adds rights to all the users on the system to all the files and folders in the specified folder:
>sudo chmod -R ugo+rw /foo/bar
----------------------------------------------------------------------------------------------------------------------------------------------------
Harden Linux
Disable root login:
>sudo vi /etc/ssh/sshd_config
Locate the line:
#PermitRootLogin yes
Press INSERT
Change it to:
PermitRootLogin no
Press escape, then type
>:wq
To save and quit
w: write
q: quit
--------------------------------------------------------------------------------------------------------------------------------------------------
Potential Useful Commands In Emergency Crisis
Get all the users logged-in to the system:
>w
Log a user out of their session:
>pkill -KILL -u username
Changing a user(s) password
>passwd user
Modifying the sudo user(s)
>sudo visudo
Show all running processes (and who is running it)
>ps aux | less
<- and -> to scroll
And to quit:
>q
And if all else fails:
>shutdown -h now
That will shut down the system as soon as you type the command
And to prevent mishaps, please log out:
>logout
That will close the terminal and the session.
----------------------------------------------------------------------------------------------------------------------------------------------------
Useful info for a server move (or just for having backups sake)
Exporting a database:
>mysqldump -p database_name > /path/to/file.sql
Importing a database:
First, we need to create the desired database we are going to import:
>CREATE DATABASE dbname
Then, do this:
>exit;
Then, we can import:
>mysql -p dbname < /path/to/file.sql
Type in the MySQL password and it will import
Create a MySQL user:
>CREATE USER 'newuser'@'localhost' IDENTIFIED BY 'password';
Then, we have to grant permissions to the user (you can set for all dbs, but i want the website to only have some permissions)
>GRANT permission ON db.table TO 'username'@'localhost';
Type of permissions that can be granted (copypasta):
ALL PRIVILEGES- as we saw previously, this would allow a MySQL user all access to a designated database (or if no database is selected, across the system)
CREATE- allows them to create new tables or databases
DROP- allows them to them to delete tables or databases
DELETE- allows them to delete rows from tables
INSERT- allows them to insert rows into tables
SELECT- allows them to use the Select command to read through databases
UPDATE- allow them to update table rows
GRANT OPTION- allows them to grant or remove other users' privileges