The cinder-volume API does not support attaching a volume via iSCSI and FC in the same call.
So when cinder asks our volume driver to map a volume to the host, and supplies both iSCSi IQN and FC WWPNs, the volume driver needs to choose which connectivity type to process.
Since OpenStack is more common in iSCSI setups, we chose to accept iSCSI by default; meaning, if a OpenStack host uses both iSCSI and FC, we will favour iSCSI by default. This can be changed in via the configuration file.
You can change the behaviour of the driver by added
infinidat_prefer_fc = true to the configuration; this will tell the driver to use the FC WWPNs in
terminate_connection for the specific volume backend in base both iSCSI IQN and FC WWPNs are supplied in the connector details.
There's no option to set this parameter with infini-openstack (our command-line tool); this needs to be done manually by modifying the cinder configuration file (the default location is /etc/cinder/cinder.conf). Here's a sample diff when applying this change:
It doesn't matter if the value is True or true