VCS/SFHA on RHEL - Disk Multipathing via O/S
Hi,
I am setting up a VCS/SFHA for the first time. I have question about clustered disks / filesystems and setting up IO Fencing.
Environment is : 2 Physical RHEL Boxes. RHEL 6.7 running VCS 6.0.50.0.
What is the supported / best way to present the disks to SFHA in regards to RHEL's multipathd?
Should I mutipath the disks at the O/S level, or is there is a mechanism in VCS/SFHA that would be able to see multiple disks on the O/S (Non Multipathed) and manage them?
Is there a Doc that describes how the O/S Disks should look before I create the vxfen disks and the shared disks / filesystems?
I hope that makes sense, regards, newbie, and thanks in advance for any help on this!
Brian
Hi Brian,
Hopeyfully you've already figured this out :)
SFHA would include the DMP and Volume Manager which handles all disk related operations. DMP is the multipathing driver and its the best out there, and you can't turn it off really, so you might as well just use it instead of the OS provided multipathing. As with most things SFHA has a hardware compatibility list that shows which arrays are supported but in most cases any disk would work.
You don't really have to do anything to get DMP working, if the OS sees the disks, DMP will jump in and handle the pathing. You can see the amount of paths on a disk by running vxdisk list "disk name".
Once you've got the disks available you can initialise them (vxdisksetup) and add them to a diskgroup (vxdg). Running the installer with the -fencing or -configure will give the option to configure fencing. All you need to do is have 3 disks in your diskgroup and tell the installer you'd like to use that one.
HTH