Apt-Cacher is a caching proxy specialized for package files from GNU/Linux distributors, primarily for Debian and Debian based distributions (like Ubuntu). This means that if you have many Debian/Ubuntu machines on your network, you just have to download the deb packages (new software, updates, distro upgrades, etc) from the internet once and the rest of the Debian/Ubuntu machines get them from Apt-Cacher cache, saving time and internet bandwidth.
Apt-Cacher Pools
Pools are where installation packages (software) are stored.
/var/cache/name-repo/pool/
How to add a Package to Apt-Cacher
Locate the Package deb file:
1. Either download the deb file from the vendor or if the package has been installed on the local server, you will find the deb file here: /var/cache/apt/archives/.
2. Copy the deb file to the pool. For all environments you can use the all pool: /var/cache/name-repo/pool/all/
note: you need to make sure that the user:group is correctly www-data:www-data. Use chown. Also, set the chmod to 664.
3. Retrieve the package metadata:
cd /var/cache/name-repo/pool/all/dpkg-scanpackages . |
4. Add the package metadata to the Packages.gz file
sudo vim /var/cache/name-repo/dists/name/all/binary-amd64/Packages.gz |
5. Make sure the filename is located in the pool folder, and the permissions are correct:
# example file pathFilename: pool/all/sensu_1.0.0-1_amd64.deb# the example can be found in our repols -l /var/cache/name-repo/pool/all/|grep sensu |
6. Test the new package:
# update the package listsudo apt-get update# test the package to make sure it is availableapt-cache policy sensu |
Find if Package Exists in Apt Repository
Check if Package Exists in Apt Repo
You should run sudo apt-get update first.
apt-cache search --names-only '^sensu.*' |
Simulate an Installation
if sudo apt-get –simulate install sensu
then echo “Package exists.”
else echo “Cannot find Package.”
fi
List Installed Packages
dpkg -l | less |
To check whether a package is installed or not:
dpkg -l vlc |
How to Install Apt-Cacher
Server Installation
1. Install apt-cacher and apache2 webserver
sudo apt-get install apt-cacher apache2
2. Enable apt-cacher
3. Edit /etc/default/apt-cacher and change autostart to 1
Note: You may have problems doing this on a machine with apache already installed.
4. Restart apt-cacher process:
sudo service apt-cacher restart
Server Configuration
1. Edit /etc/apt-cacher/apt-cacher.conf Uncomment the following line:
allowed_hosts = * Or set allowed_hosts to something appropriate.
allowed_ssl_locations = dl.bintray.com:443,dl.bintray.com,archive.cloudera.com[,<additional ssl repos]
Apt Cacher now uses IPv6 addressing so you may find you need something like: allowed_hosts=::ffff:192.168.0.1/24, for example, if you want to restrict hosts to a common home subnet.
2. Change the admin_email email address to something meaningful.
3. By default apt-cacher may have problems with upgrades of ubuntu from one version to another when running do-release-upgrade -d This can be fixed by uncommenting the line beginning with installer_files_regexp and modifying it from:
installer_files_regexp = ^(?:vmlinuz|linux|initrd\.gz|changelog|NEWS.Debian|UBUNTU_RELEASE_NAMES\.tar\.gz(?:\.gpg)?|(?:Devel|EOL)?ReleaseAnnouncement(?:\.html)?|meta-release(?:-lts)?(?:(?:development|proposed))?)$
to:
installer_files_regexp = ^(?:vmlinuz|linux|initrd\.gz|changelog|NEWS.Debian|[a-z]+\.tar\.gz(?:\.gpg)?|UBUNTU_RELEASE_NAMES\.tar\.gz(?:\.gpg)?|(?:Devel|EOL)?ReleaseAnnouncement(?:\.html)?|meta-release(?:-lts)?(?:-(?:development|proposed))?)$
Note the addition of [a-z]+\.tar\.gz(?:\.gpg)? in the regexp
4. Restart apt-cacher:
sudo /etc/init.d/apt-cacher restart
5. Test apt-cacher by pointing your web browser to http://server01:3142/apt-cacher to verify that it’s running: http://aptproxy.server01:3142/
For example:
The contents of the /etc/apt/apt.conf.d/01proxy file should be:
Acquire::http::Proxy “http://aptproxy.server01:3142/”;
APT::Get::AllowUnauthenticated 1;
6. Import existing cached Packages
7. Import any existing packages into the cache by creating symlinks:
sudo /usr/share/apt-cacher/apt-cacher-import.pl -l /var/cache/apt/archives
Distributions
/var/cache/name-repo/dists/name/
Pools
/var/cache/name-repo/pool/
Note: on the apt-cacher server, the apt-get deb files are located on /var/cache/apt/archives/
Client Configuration
Use as a proxy to APT
1. In a terminal, type:
sudo vi /etc/apt/apt.conf.d/01proxy
2. Inside your new file, add a line that says:
Acquire::http::Proxy “http://<IP address or hostname of the apt-cacher server>:3142”;
Note: The entire file will look like this:
Acquire::http::Proxy “http://aptproxy.server01:3142/”;
APT::Get::AllowUnauthenticated 1;
3. Update the /etc/apt/apt.conf.d/10periodic file:
Note: The entire file will look like this:
APT::Periodic::Update-Package-Lists “1”;
APT::Periodic::Download-Upgradeable-Packages “1”;
APT::Periodic::AutocleanInterval “1”;
APT::Periodic::Unattended-Upgrade “1”;
APT::Periodic::Verbose “2”;
4. Make sure Unattented-Upgrade::Automatic-Reboot is set to “True” in this file: /etc/apt/apt.conf.d/50unattended-upgrades
Unattended-Upgrade::Automatic-Reboot “true”;
Note: Next time any of your machines needs a deb package, it will ask Apt-Cacher for it. If this package was asked previously by any of the other machines, Apt-Cacher will have a copy and will deliver it. Otherwise, it will fetch it from the internet repositories, keep a local copy and deliver it.