I'm running RHEL 5.2 connected to a NetApp over FC. The server is running a database on mpathNN devices that can not be stopped. I need to add a new LUN and give it a specific alias (rather than mpathNN). I know how to set this up in multipath.conf, but I don't know the wwid of the LUN yet. I also know this can be achieved by restarting multipathd, but don't know if this is safe.
Is it safe to restart multipathd without i/o interruption?
or, is there another way I can enable the alias specified in multipath.conf once I've presented it to the host?