Milton

The bc command in Linux enables the terminal to be used as the basic scientific calculator. Additionally, bc command in Linux can also work with the files.

The whitespaces in the Makefile cause this error, which is fixed using the vim editor’s syntax features that filter the whitespaces and tabbed spaces.

To uninstall packages with apt package manager in Debian-based distributions, we can use the apt remove, apt autoremove, and apt purge commands.

We can temporarily set the SELinux permissive mode with the “sudo enforce 0” command and permanently with “SELINUX=permissive” in the /etc/selinux/config file.

In Linux, vim plugins can be installed easily using the vim plugin manager or manually adding plugins to vim, as explained with practical plugin installations.

To set up Outlook on Linux, install an email client named Prospect-Mail and then use your Outlook credentials to sign in through the Prospect-Mail.

The XFS file system should be used if the file sizes are large, while the ext4 is more beneficial when the I/O workload is greater or CPU resources are less.

This guide explains the functionalities, strengths, and weaknesses of the Linux Operating system’s Btrfs and Ext4 file systems.

The nginx 504 gate time-out error can be resolved by increasing the proxy, and FastCGI connect, read and send times to more than default time-out of the Nginx.

The best network scanners in Linux are Nmap, Angry IP Scanner, Fping, Nessus, OpenVAS, and Arp Scan, whose details and installation methods are explained.

There are two methods to add the users to sudoers in Linux: adding the user to the sudo group or adding to the default sudo /etc/sudoers file.

The wildcards to find the specific filename, the file starting or ending with a specific character, number, or extension, as explained in this guide.

We can list GPG keys in Linux that help the users to view the information of public keys, secret keys, signatures, and fingerprints of the GPG keys.

To create a user with a different home directory in Linux, we can use the “d” option of the useradd command as performed in this article.

The OpenSSL S_Client command can be used to test, debug, disable the client-side connection and print, check, verify, and specify cipher for SSL certificates.

Multiple methods are used to do a port scan in Linux, which are nmap, netcat, ss, netstat, lsof, and telnet commands. All these are practically demonstrated here.

Several methods to detach a session in Tmux are explained in this guide with the help of examples that include shortcut, command, and GUI methods.

To list Tmux sessions “tmux ls”, “tmux list-sessions” and to attach “tmux attach-session -t ”, “tmux attach -t sessionID” commands are used.

The DNS converts the domain name to a universally readable ip address, and to search the DNS history in Linux, use the “dig”. “Host” and “nslookup” commands.

All the Tmux sessions in Linux can be killed by using the “pkill -f tmux”, “tmux kill-server”, and “tmux kill-session -a” commands and using the system monitor.

The SSH port forwarding tunnels one server traffic to another on a specific port in Linux that is done using the “L” option with the SSH command.

The SSH default port is changed due to security reasons, and to change it, edit the ssh configuration file “/etc/ssh/sshd_config” or run the “sed” command.

To format a drive or partition in Linux, we can use the fdisk, gdisk, mkfs command-line methods, while the GNOME Disks GUI method can also be used.

We can find the UUID of the storage devices in Linux using the “blkid”, “lsblk”, “/dev/disk/by-uuid” and “/etc/fstab” methods as discussed in this article.

The SSL certificate errors in Linux can be ignored or hidden by using the “-k” or “–ignore” options with the curl command or updating the CA certificates.

In Linux, the Nmap scans for online hosts using specific communication protocols, port numbers, live hosts, and IP addresses within a network.

The SUID permissions are same as the user (owner), GUID is similar to the group, and with sticky bits can delete directories for yourself only, not for others.

SSH too many authentication failure errors can be fixed using the correct SSH key, increasing the MaxAuth limit, and using authentication identity keys only.

The tls/ssl error occurs if the required libraries are missing which can be removed by installing the “glib-networking” package or updating the ca-certificates.

The dry-run rsync command in Linux is used to test the output without any changes in the system to sync data between local and remote servers using its options.

We can create, remove, copy, move, read, write, and edit a file having a filename with spaces in Linux, using the “quotes” or “backslash” within the filenames.

This error occurs when the root user account is not set up correctly. To fix the error, set the root user password for MySQL and log in again.

The update-grub command not found error can be resolved by running the “grub-mkconfig” command or adding the grub-mkconfig $Path to the grub default file.

In Linux, to move a file to another directory, the “mv” command is used, or choose the “Move to…” option after selecting the file from GUI as discussed.

To find the process id, use the commands “pidof”, “pgrep”, “pstree”, or “ps aux”. And to kill it, use the “killall , or “kill -9 ”.

To fix the “too many open files” error in Linux, increase the opened files limit for the current session or for permanent.

The SSH could not resolve hostname error can be fixed by using the correct hostname & ip address or adding a manual SSH entry in the “/etc/hosts” file.

In Linux, the User ID (UID) stores all the user’s information which can be used with different commands like id, cat, getent, and awk to find users information.

We can find & replace with the substitute command or find the word with forward slash “/” and replace with dot sign “.”. Read this post for further details.