Dpkg

Missing key id NO_PUBKEY

<source lang=bash>

1. apt-key adv --keyserver keyserver.ubuntu.com --recv <keyid>

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Package source which resolves to IPv6 adresses causes sometimes problems

To force the usage of the returned IPv4 adresses do: <source lang=bash> $ echo 'Acquire::ForceIPv4 "true";' | sudo tee /etc/apt/apt.conf.d/99force-ipv4 </syntaxhighlight>

Packages from a specific source

Prequisite: dctrl-tools

<source lang=bash> sudo apt-get install dctrl-tools </syntaxhighlight>

Show packages

For example all PPA packages <source lang=bash> sudo grep-dctrl -sPackage . /var/lib/apt/lists/ppa*_Packages </syntaxhighlight>

From where is my package installed?

<source lang=bash> sudo apt-cache policy <package> </syntaxhighlight>

Does my file match the checksum from the package?

If you fear you are hacked verify your binaries!

Prequisite: debsums

<source lang=bash> sudo apt-get install debsums </syntaxhighlight>

Verify packages

<source lang=bash> sudo debsums <package name> </syntaxhighlight>

<source lang=bash> $ sudo debsums unhide.rb /usr/bin/unhide.rb OK /usr/share/doc/unhide.rb/changelog.Debian.gz OK /usr/share/doc/unhide.rb/copyright OK /usr/share/lintian/overrides/unhide.rb OK /usr/share/man/man8/unhide.rb.8.gz OK </syntaxhighlight>