The format of the cron job is as follows: 1 = The minute after the hour that you want it done 2 = The hour you want it done (Military Time) 3 = Day of the Month 4 = Month of the Year 5 = Day of the week 6 = ‘command’ that you want …

check for bad blocks on a hard drive: badblocks -vv /dev/sda3 > badblocks.log & The command above will check for badblocks on the partition /dev/sda3 and save the results to the log file badblocks.log checks for badblocks and it writes the results to: badblocks.log If you want to check a specific drive or partition you …

In order to add a user you should create their group first or decide which preexisting group you will assign them to. If you’re adding a new group for the user: Add the group: groupadd $group Then add the user adduser -g $group -d /home/$username $username This will add a user with the username $username …

This is a great method to execute commands on a remote server without actually opening another window and running the command directly. Additionally, if you have a server monitor setup this is a great way to restart services if a service crashes. We often use this method on internal servers and when a service outage …

It’s often more secure to establish key logins, or you may want to allow a server to automatically ssh to another to copy over backup files or to run commands. To enable SSH keys: On the server that’s going to make the connection: ssh-keygen -t rsa The command above places the public key that you …

It’s often necessary to backup a set of files, however you don’t want to archive an entire folder or site. To accomplish this task simply create a text file called filestotar.txt. Then place the full path and file name of each file that you want included in the archive. Then run: tar -cvf backup.tar –files-from=filestotar.txt …

Backups or Archives are usually very large and it can take forever to extract all of the files to retrieve a specific folder. Additionally, the drive may be close to it’s maximum capacity and extracting the full archive may not be an option. Here’s how to extract a specific folder from a tar archive: tar …