Compellent SANs can do a mix of both Fibre connections and iSCSI connections to the same volume. So some of our customers are looking for ways to do more complex set ups with iSCSI as a failover situation behind multiple fibre connections. Multibus works fine if they are using like connections, but if not, we wanted to be able to make sure that the faster connections come up on top. --- Jim Lester -----Original Message----- From: dm-devel-bounces@xxxxxxxxxx [mailto:dm-devel-bounces@xxxxxxxxxx] On Behalf Of Konrad Rzeszutek Sent: Wednesday, August 13, 2008 9:52 AM To: device-mapper development Subject: Re: Custom priority callout On Wed, Aug 13, 2008 at 09:32:27AM -0500, Jim Lester wrote: > I know that the issue with writing custom priority callouts is that they > need to be running in RAM so that if the disk is lost, it can be called > again. > > My question is, if I write a custom binary file, and statically compile > it so it doesn't link against any libraries, does multipath > automatically load it into RAM because it mentioned in the config file, > or is their other code that has to be modified to load it. It will most certainly be evicted from memory. You might be better of using the more recent versions of multipath and making your custom priority callout as one of the libraries in the 'libprio' directory. You will need to modify the Makefile and the libprio.c to include your code. Keep in mind if you segfault in it you will bring down multipathd with it. Oh, and do post it on this mailing list so that multipath can nativly support the Compellant path priority code (I thought it was multibus??) -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
