By default XenServer 5.5 uses source-based ARP load balancing (balance-slb or mode 7) for bonding. If this is needed to be changed to a different mode all that is needed to do is edit the file /opt/xensource/libexec/interface-reconfigure on line 863. Do this using the following command:

vi /opt/xensource/libexec/interface-reconfigure +863

once there the value for mode can be changed from “balance-slb” to any supported mode. Here is a list of the modes:

balance-rr active-backup balance-xor broadcast 802.3ad balance-tlb balance-alb balance-slb

See Linux Channel Bonding for more information on the types of bond modes. Unfortunately I could not find much information on balance-slb.

To check if the bond mode change worked correctly run

cat /proc/net/bonding/bond<bondnumber>

Run ifconfig to find the bondnumber.

This will list the bond mode and the slave interfaces to the bond.