Globus Toolkit on multi-homed hosts

On HP XC Clusters, it is recommended that one obtain a new virtual IP address and corresponding hostname (GCHN) specifically for globus (see Globus on XC Clusters for more information). Similarly, on Alpha TruCluster or AlphaServer SC systems, it may be desirable to use the existing cluster alias for the GCHN (see Globus on TruClusters for more information). If either of these methods are chosen, skip ahead to the next section. Otherwise, select the GCHN by identifying the name of an externally-resolvable interface as follows:

• Determine the IP address of an external interface. A list of interfaces (and their addresses) is usually available from the command

      $ ifconfig -a
  

  On the XC Cluster, use the head node (if it's externally accessible) or one of the login nodes.
• Map this address back to its canonical host name. Note that, it may matter if the name is fully-qualified (the client-side host name comparison uses a simple string match). If, after reading gethostbyaddr(3), this process seems confusing, compile and run the "ghba.c" program with the interface address as the argument (e.g. "ghba 192.168.1.1"); it will display the canonical host name for an address.

If the canonical host name is not fully-qualified, now would be a good time to change this. Strictly speaking, one could configure Globus to use an unqualified host name for Globus and its certificates, however that would require all clients to resolve the address to its unqualified form (e.g., through an entry in the "/etc/hosts" file). And, managing the host list would likely prove unwieldy as more nodes are added to a grid.

Build the Globus Toolkit from source or binary bundles following the instructions available from Globus. After the build completes:

• Set the $GLOBUS_HOSTNAME environment variable to the GCHN (as determined above):

      (sh)  $ GLOBUS_HOSTNAME=host.dom.ain; export GLOBUS_HOSTNAME
      (csh) % setenv GLOBUS_HOSTNAME host.dom.ain
  

  Then run either "make install" (for GT4) or the Globus post-install script (for GT2). Setting this environment variable is necessary because many configuration files created during the post-install process have hardcoded host names (e.g., some job managers and MDS configuration files). By setting $GLOBUS_HOSTNAME before the installation step, these hardcoded host names will be correctly initialized to the GCHN.
• Request the Host and LDAP certificates, being sure to use the GCHN.
• Use env(1) to set $GLOBUS_HOSTNAME for Globus services launched out of inetd(8). For example:

      gsiftp stream tcp nowait root /usr/bin/env \
         env GLOBUS_HOSTNAME=host.dom.ain LD_LIBRARY_PATH=/globus/active/gtk/lib \
         /globus/active/gtk/sbin/globus-gridftp-server -i
  

• Follow the Globus configuration instructions (add ports to "/etc/services", etc.).
• Ensure that local users set $GLOBUS_HOSTNAME to the GCHN before running any applications.
• Globus should now function on the multi-homed host (but not yet on an XC Cluster, TruCluster or AlphaServer SC). Any messages coming from Globus utilities of the form:

      GRAM Job submission failed because authentication failed:
          Unexpected Gatekeeper or Service Name
          Mutual authentication failed 
      Expected target subject name= [...]
      Target returned subject name= [...]
  

  indicate the wrong host name was used in one of the preceding steps.