rdesktop is an open source client for Microsoft's RDP protocol. It is known to work with Windows versions ranging from NT 4 Terminal Server to Windows 2012r2 RDS. rdesktop currently has implemented the RDP version 4 and 5 protocols.
rdesktop uses a GNU-style build procedure. Typically all that is necessary to install rdesktop is the following:
% ./configure
% make
% make install
The default is to install under /usr/local. This can be changed by adding
--prefix=<directory> to the configure line.
The smart-card support module uses PCSC-lite. You should use PCSC-lite 1.2.9 or
later. To enable smart-card support in the rdesktop add --enable-smartcard to
the configure line.
If you have retreived a snapshot of the rdesktop source, you will first
need to run ./bootstrap in order to generate the build infrastructure.
This is not necessary for release versions of rdesktop.
Connect to an RDP server with:
% rdesktop server
where server is the name of the Terminal Services machine. (If you receive "Connection refused", this probably means that the server does not have Terminal Services enabled, or there is a firewall blocking access.)
You can also specify a number of options on the command line. These are listed in the rdesktop manual page (run "man rdesktop").