Linux Error 13: Permission denied – Are you root? signals that a process lacks the necessary privileges to access a file, directory, or resource, often prompting elevation to root. This errno 13 stems from Linux’s strict permission model, designed to enhance security by restricting operations on system-critical areas. Please, see how to Configure failover for ManageEngine Password Manager Pro, how to setup and configure Jitsi as SoftPhone, and Access EC2 Linux Instance via the Password.

What Causes It?

The encountered error message, “E: Could not open lock file /var/lib/dpkg/lock – open (13: Permission denied),” typically occurs when trying to perform package management tasks in Linux without the necessary root privileges. This issue, often denoted as “Linux Error 13,” indicates that the system is preventing access to the essential dpkg lock file, which is crucial for managing software packages.

Apt and dpkg require exclusive write access to directories like /var/lib/dpkg/ to manage package databases and locks, which non-root users cannot touch due to 644/755 permissions owned by root. Running as a normal user triggers errno 13 on open(), blocking the operation. This is common in fresh installs or when forgetting sudo after prior commands

This Linux Error 13 error simply means you are not the root user.

me@linuxbox ~#apt-get update
E: Could not open lock file /var/lib/dpkg/lock - open (13: Permission denied)
E: Unable to lock the administration directory (/var/lib/dpkg/), are you root?

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Solution

Simply install it using the sudo to install any package as a root user. This occurs because you are using a normal user account. Therefore, prefix with sudo for temporary root escalation: sudo apt-get update && sudo apt-get upgrade refreshes lists and upgrades packages safely. If sudo prompts for a password and fails, verify your user is in the sudoers group via groups or add with usermod -aG sudo username (as root).

To reiterate, ensure that you have superuser privileges by using the “sudo” command before the package management operation. For instance, you can employ the following command: “sudo apt-get update” to refresh the package list. By appending “sudo” to your package management commands, you gain the necessary authorization to access system files and overcome the permission denied obstacle.

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Prevention Tips for “Linux Error 13: Permission denied – Are you root”

Remember, maintaining proper permissions is vital for a secure and stable Linux system. So, whenever you encounter “Linux Error 13,” simply prepend “sudo” to your package management commands to ensure successful execution.

That is, always chain sudo for apt workflows: sudo apt update && sudo apt upgrade -y to avoid repetition.
Check for stuck locks first: sudo rm /var/lib/dpkg/lock-frontend if another process hung (rare, but verify with ps aux | grep apt)

Command	Purpose	Privilege Needed
`apt-get update`	Fails with Error 13	sudo
`sudo apt-get update`	Succeeds, refreshes repos	User in sudoers
`apt-get upgrade`	Updates packages	sudo

Sudo logs all commands in /var/log/auth.log for auditing, unlike full su shells. Ideal for business environments handling infrastructure. Avoid default root logins; configure sudo for least-privilege access to maintain stability and cybersecurity.

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