iSCSI interface and offload support is only present since Kilo. Compute supports open-iscsi iSCSI interfaces for offload cards. Offload hardware must be present and configured on every compute node where offload is desired. Once an open-iscsi interface is configured, the iface name (iface.iscsi_ifacename) should be passed to libvirt via the iscsi_iface parameter for use. All iscsi sessions will be bound to this iSCSI interface. Currently supported transports (iface.transport_name) are be2iscsi bnx2i cxgb3i cxgb4i qla4xxx ocs . No configuration changes are needed outside of Compute node. iSER is currently supported via the separate iSER LibvirtISERVolumeDriver and will be rejected if used via the iscsi_iface parameter.

Note the distinction between the transport name (iface.transport_name) and iface name (iface.iscsi_ifacename). The actual iface name must be specified via the iscsi_iface parameter to libvirt for offload to work. The default name for an iscsi iface (open-iscsi parameter iface.iscsi_ifacename) is in the format transport_name.hwaddress when generated by iscsiadm. iscsiadm can be used to view and generate current iface configuration. Every network interface that supports an open-iscsi transport can have one or more iscsi ifaces associated with it. If no ifaces have been configured for a network interface supported by an open-iscsi transport, this command will create a default iface configuration for that network interface. For example : # iscsiadm -m iface default tcp,<empty>,<empty>,<empty>,<empty> iser iser,<empty>,<empty>,<empty>,<empty> bnx2i.00:05:b5:d2:a0:c2 bnx2i,00:05:b5:d2:a0:c2,5.10.10.20,<empty>,<empty> cxgb4i.00:07:43:28:b2:58 cxgb4i,00:07:43:28:b2:58,102.50.50.80,<empty>,<empty> qla4xxx.00:c0:dd:08:63:ea qla4xxx,00:c0:dd:08:63:ea,20.15.0.9,<empty>,<empty> The output is in the format : iface_name transport_name,hwaddress,ipaddress,net_ifacename,initiatorname. Individual iface configuration can be viewed via # iscsiadm -m iface -I IFACE_NAME # BEGIN RECORD 2.0-873 iface.iscsi_ifacename = cxgb4i.00:07:43:28:b2:58 iface.net_ifacename = <empty> iface.ipaddress = 102.50.50.80 iface.hwaddress = 00:07:43:28:b2:58 iface.transport_name = cxgb4i iface.initiatorname = <empty> # END RECORD Configuration can be updated as desired via # iscsiadm -m iface-I IFACE_NAME--op=update -n iface.SETTING -v VALUE All iface configurations need a minimum of iface.iface_name, iface.transport_name and iface.hwaddress to be correctly configured to work. Some transports may require iface.ipaddress and iface.net_ifacename as well to bind correctly. Detailed configuration instructions can be found here http://www.open-iscsi.org/docs/README