Understanding the GUID Routing Order File (SM Configuration)

Version 11

    The guid_routing_order_file allows you to manage the order in which the SM processes the destination LIDs in the calculations of output port as part of  MinHop or Up/Down routing algorithms (only those).

    The requested GUIDs should be provided in the text file (one per line). The destinations corresponding to the provided GUIDs will get precedence during the routing calculations before the rest of destinations in the fabric.

     

    References

     

    Note: The order of GUID appearance in the file is important, GUIDs appearing earlier in file will have precedence over the GUIDs appearing later.

    Using this technique can improve load balancing towards a specific set of end ports (e.g. storage nodes or other service nodes requiring high throughput).

     

    Note: If HCA cards are replaced in the servers appearing in the GUID order file, the file must be updated accordingly to keep efficient routing in the fabric.

    After file update, one needs to run “pkill –HUP opensm” to apply the changes without restarting opensm application.

     

    In addition, a guid_routing_order_no_scatter opensm parameter can be used in couple with GUID order file. If scatter-ports (randomization of the output port) option is set to non-zero, guid_routing_order_no_scatter defines whether or not a randomization should be applied to the destinations GUIDs mentioned in GUID order file.

     

    Configuration

    There are two options for adding the GUIDs to the GUID routing order file depending on if the SM is running on a host or Unified Fabric Manager (UFM).

    While you follow the same procedure, the files you need are located in different paths.

     

    Note: This parameter is not applicable when the SM is running on a switch.

     

    UFM

    In case the SM operates within UFM:

     

    1. Open the opensm.conf file and add:

    routing_engine updn

    guid_routing_order_file /opt/ufm/files/conf/opensm/guid_routing_order.conf

     

    2. Add guids to the guid_routing_order.conf file:

    0xe41d2d030031e7c8

    0xe41d2d030031e7c7

    0xe41d2d030031e7c5

     

    3. Restart the UFM service:

    /etc/init.d/ufmd stop

    /etc/init.d/ufmd start

    Host

    In case the SM Operates within a Host:

     

    1. Open the opensm.conf file and add:

    routing_engine updn

    guid_routing_order_file /etc/opensm/guid_routing_order.conf

     

    2. Add guids to the guid_routing_order.conf file:

    0xe41d2d030031e7c8

    0xe41d2d030031e7c7

    0xe41d2d030031e7c5

     

    3. Restart the openSM service:

    /etc/init.d/opensmd stop

    /etc/init.d/opensmd start