I've seen several times people with unmet dependencies, which apt-get doesn't tells straightforward what's the problem, like this one:The following packages have unmet dependencies: libgl1-mesa-dri:i386 : Depends: libdrm-intel1:i386 (>= 2.4.38) but it is not going to be installed                        Depends: libdrm-nouveau2:i386 (>= 2.4.38) but it is not going to be installed                        Depends: libdrm-radeon1:i386 (>= 2.4.31) but it is not going to be installed                        Depends: libdrm2:i386 (>= 2.4.38) but it is not going to be installed                        Depends: libglapi-mesa:i386 but it is not going to be installed libgl1-mesa-glx:i386 : Depends: libdrm2:i386 (>= 2.3.1) but it is not going to be installed                        Depends: libglapi-mesa:i386 (= 9.2.1-1ubuntu3) but it is not going to be installed                        Depends: libx11-6:i386 (>= 2:1.4.99.1) but it is not going to be installed                        Depends: libxcb-dri2-0:i386 (>= 1.8) but it is not going to be installed                        Depends: libxcb-glx0:i386 (>= 1.8) but it is not going to be installed                        Depends: libxcb1:i386 but it is not going to be installed                        Depends: libxdamage1:i386 (>= 1:1.1) but it is not going to be installed                        Depends: libxext6:i386 but it is not going to be installed                        Depends: libxfixes3:i386 but it is not going to be installed                        Depends: libxxf86vm1:i386 but it is not going to be installedI know that walking through all dependencies apt-get install libgl1-mesa-dri:i386 libdrm-intel1:i386 until I hit something is available, but in this case it will be a painful job due the amount of packages. Is there an easier way to do this?
What information do I need to solve an APT dependency issue?
apt
There's a bunch of information that would help you:Include the complete command that caused the issue in first place.Include information about the packages involved with:apt-cache policy name-of-packages-involvedSo, in your case is the output of apt-cache policy libgl1-mesa-dri:i386 libdrm-intel1:i386 libgl1-mesa-glx:i386 libdrm-nouveau2:i386 minimum.The output of sudo apt-get check and possibly sudo dpkg -C also improved the chances you have.The complete output of sudo apt-get update and cat /etc/apt/sources.list{,.d/*.list} can help in certain situations.In case you are trying to install a package, the output of aptitude's why-not command to easily figure out:aptitude why-not sysvinit-corei A systemd-sysv Breaks sysvinit-coreWhen asking for help about solving this issues, always include the full output of everything asked, this would expedite the solution of the problem.