fiber channel question

[Quin Hammes]

We have 2 L class servers with two fiber channel cards, each one is connected to a hub that is in turn connected to a array (one has two SCSI/FIBER muxes between it and the fiber because its a SCSI disk array while the other one is fiber). this was recommended for service guard in order to allow for hardware redundancy. the disks are going to be mirrored to each other eventually but right now we have a problem. One of the machines is down for maintance so it is not involved. the other machine is mounting just one of the disk arrays but their is two possible paths to those disk arrays because of the two fiber cards on the system so what seems to be happening is that when the system boots up, it sometimes find another path to the disk so it creates different device files which of course means that we can not mount the volume groups since the Physical volume device files are no longer on the system. What is wrong here? For example the first time we boot we might get a device file of /dev/dsk/c3t1d0 while the next time we might get /dev/dsk/c3t0d0 which of course screws up everything. any hints? Has anyone done a mirrored two path fiber construct like we have done? Any information or feedback would be appreciated. thanks.

Quin

[Paula J Frazer-Campbell · Accepted solution]

Hi
See man setboot also:-

setboot -a HW
where HW is your hardwrae path to the drive
If you want the auto boot option use the "-b on" args.

If no options are specified, setboot displays the current values of
variables in the stable storage.


HTH

Paula

[Carlos Fernandez Riera]

I understand your disks can take diferents id each reboot.

My experience w/ FC10 disk is that FC cables are not correctly attached.

Shutdown and try to disconect/reconect cables. Stop boot and use search [SEA] at ISL prompt.

[Bill McNAMARA_1]

this should not happen, your d array behind the mux
should be seen before the reboot thus device files should not be
created. ?your c3t1 change from c1t0 suggests that you
are accessing via the other controller. . I suspect that your controller hasn't failed.
You need to make sure that you have your
lvm pvlinks set up correctly and identically
on both systems.
Make sure aswell that your mux is not running in split mode or else
the scsi busses
0 and 1 from the mux will only be seen by the FCA, and
2,3 only by FCB.

Send an ioscan from each system for more info.