HP xw3400 User Manual page 112

Summary
The following is a list of frequently asked questions and the answers concerning 64-bit support on HP
Linux® workstations.
Q. When will a 64-bit Red Hat Linux OS be supported on HP's workstations with EM64T technology
from Intel and AMD64 technology from AMD®?
A. Today! HP's Intel®-based and AMD-based Workstations all support 64-bit Red Hat Linux pre-
installed and with the Red Hat box set and the HP Installer Kit for Linux.
Q. What version of Red Hat Linux will support 64-bit?
A. Red Hat Enterprise Linux 3, WS (RHEL 3,WS) has both a 32-bit version and a 64-bit version. HP
pre-installs the 64-bit version on all workstations and supports both 32-bit and 64-bit with the Driver
CD in the HP Installer Kit for Linux.
There will not be any 64-bit versions of previous Red Hat releases (such as Red Hat Linux 7.3)
supported on HP Workstations.
Q. Do I have to have two versions of my 64-bit application—one for Intel-based workstations and one
for AMD workstations?
A. NO! Intel defined the EM64T extensions to the x86 architecture to be exactly compatible with the
AMD64 instructions. As long as you do not use any special Intel or AMD options to the compiler
when you build your application (such as 3dnow), your application should just run on either an Intel
system or an AMD system.
Q. Are there other 64-bit distributions of Linux that will work on the HP Workstations?
A. Yes, HP has tried other distributions on the HP Workstations but Red Hat Enterprise Linux is the
only HP-supported Linux distribution.
Q. Can I run 32-bit apps on a 64-bit Linux OS? How does this work? Will this work for all 32-bit
apps?
A. Yes, as long as the runtime support (mainly shared libraries) for the application exists on the
system. HP has noticed that some versions of Linux are much better than others at providing a
complete set of 32-bit libraries. The Linux convention for having 32-bit libraries and 64-bit libraries on
the same OS is to have companion library directories. The 32-bit libraries are in the conventional
locations: /lib, /usr/lib, /usr/X11R6/lib, etc., whereas 64-bit libraries just append 64 to the
directory name such as /lib64, /usr/lib64, and /usr/X11R6/lib64. This also includes 32-bit versions
of the graphics libraries, which HP has included from the graphics vendors.
Q. What do I do if the 32-bit apps do not run due to missing shared libraries?
A. Simple solution is to get the library from Red Hat's 32-bit RHEL 3 distribution and put it on your
system in the appropriate directory and report the missing library to Red Hat through your Red Hat
Network subscription. This will help Red Hat to get the right set of 32-bit libraries needed for most
apps in future releases.
A more robust solution is to do the following:
rpm2cpio <32-bit rpm>
rpm -i --force <64-bit rpm>
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:<32-bitpath>
> <32-bitpath>
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