IDA is still, as of this writing (December 23rd, 2015), a 32-bit application and both IDA & its installer(*) require certain 32-bit libraries to be present on your Linux system before they can run.
Here is the list of commands you will have to run in order to install those dependencies, for the following systems:
Note: we cannot possibly install & try IDA on all flavors/versions of all Linux distributions, but we will do our best to update this post with relevant information, whenever we learn of a distribution requiring special attention.
(*) that is: if you want the installer to run a graphical interface, instead of a command-line one.
The following should allow IDA to run on most Linux systems deriving from Debian distributions:
sudo dpkg --add-architecture i386 sudo apt-get update sudo apt-get install libc6-i686:i386 libexpat1:i386 libffi6:i386 libfontconfig1:i386 libfreetype6:i386 libgcc1:i386 libglib2.0-0:i386 libice6:i386 libpcre3:i386 libpng12-0:i386 libsm6:i386 libstdc++6:i386 libuuid1:i386 libx11-6:i386 libxau6:i386 libxcb1:i386 libxdmcp6:i386 libxext6:i386 libxrender1:i386 zlib1g:i386 libx11-xcb1:i386 libdbus-1-3:i386 libxi6:i386 libsm6:i386 libcurl3:i386
It is necessary to also run those commands, for IDA to present a usable GUI on Xubuntu 15.10
sudo apt-get install libgtk2.0-0:i386 gtk2-engines-murrine:i386 gtk2-engines-pixbuf:i386
IDA will require the following packages to be installed, in order to run properly on RHEL 7.2 (and probably any other RPM-based distribution) :
redhat-lsb-core.i686 glib2.i686 libXext.i686 libXi.i686 libSM.i686 libICE.i686 freetype.i686 fontconfig.i686 dbus-libs.i686