Troubleshooting guide

If you wish the driver to auto-load at boot, you must create appropriate links in the

/etc/rcN directories to the /etc/init.d/gm script. Alternatively, you may start and stop the

driver manually using

su root

/etc/init.d/gm start

/etc/init.d/gm stop

su root

/etc/init.d/gm restart

Note:

1. GM is not in the critical performance path so it does not need to be built with

specialized compilers and flags. GM should be built with Gnu gcc and only built

with -O level of optimization.

2. GM should be installed in an NFS-mounted area.

3. gm_install_drivers and /etc/init.d/gm start need to be run on all nodes in the

cluster!

4. The kernel header files MUST match the running kernel exactly: not only should

they both be from the same version, but they should also contain the same kernel

configuration options. (Be careful with RedHat kernel packages.)

5. By default, we also assume that you have PCI64, PCI64A, PCI64B, or PCI64C

NICs. (PCI32 NICs are not supported in gm-1.6.3 and later.)

6. If a host is rebooted, you must reload the GM driver (and rerun the GM mapper).

The most common gm_install_drivers failures are:

• APIC IRQ conflicts (encountered on several Tyan and AMD motherboards)

• Running kernel / source kernel mismatch (commonly encountered with

RedHat kernel packages)

• AGP (nVidia, ATI) conflicts

• Defective or inadequate riser cards

The solutions for these problems are summarized in the FAQ entry “GM Installation

fails. What does this error message mean?”.

Undoubtedly, if you encounter an issue on a specific motherboard or version of Linux,

someone else has too, and it will be documented on the Myricom web site. If not, contact

us at help@myri.com.

3. Run the GM-1 mapper

cd <install_path>/sbin/

su root

./mapper ../etc/gm/map_once.args