Sudo apt update Page
sudo apt update
Return to apt install, apt, dnf-yum, pacman
It's a fundamental command used in Debian-based Linux distributions (like Ubuntu, Debian, and Linux Mint) to refresh the list of available packages and their versions from the configured software repositories.
**Here's a breakdown of what `apt update` does:**
1. **Connects to Repositories:** `apt update` reaches out to the software repositories specified in your system's configuration files (usually located in `/etc/apt/sources.list` and `/etc/apt/sources.list.d/`).
2. **Retrieves Package Information:** It downloads the latest package lists from these repositories, which include information about available packages, their versions, dependencies, and other metadata.
3. **Updates Local Cache:** The downloaded package information is stored in a local cache on your system. This cache is then used by other `apt` commands, such as `apt install` or `apt upgrade`, to determine which packages can be installed or updated and their dependencies.
**Key Points:**
* **No Package Downloads:** `apt update` itself doesn't download any actual package files; it only updates the local information about available packages.
* **Essential Before Upgrades/Installs:** It's crucial to run `apt update` before performing any package installations or upgrades using `apt` to ensure you have the most up-to-date information about available packages and their dependencies.
* **Requires Root Privileges:** You typically need to run `apt update` with root privileges (using `sudo` or logging in as root) as it modifies system files related to the package cache.
* **Network Connection:** An active internet connection is required to connect to the software repositories and download the package lists.
**Example Usage:**
```bash
sudo apt update
```
This command updates the package lists for all configured repositories.
**Remember:**
* Regularly running `apt update` helps keep your system's package information current, allowing you to install the latest software versions and security updates.
* After running `apt update`, you can use `apt list --upgradable` to see a list of packages that have updates available.
* **Debian `apt` Manual Page:**
* URL: [https://manpages.debian.org/stable/apt/apt.8.en.html](https://manpages.debian.org/stable/apt/apt.8.en.html)
* **Ubuntu `apt` Command Line Interface (CLI) Guide:**
* URL: [https://manpages.ubuntu.com/manpages/focal/en/man8/apt.8.html](https://manpages.ubuntu.com/manpages/focal/en/man8/apt.8.html)
* **How To Use `apt update` and `apt upgrade` on Ubuntu:**
* URL: [https://linuxize.com/post/how-to-use-apt-command/](https://linuxize.com/post/how-to-use-apt-command/)
{{navbar_apt}}
{{navbar_footer}}