Fiber channel multipathing and mounting?

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1

Hey all -

So we’re trying to upgrade all of our boxen with multiport fiber channel adapters so that we might run multiple cables, one to each of our fiber channel switches, for some extra redundancy. I haven’t yet done this, but as we know, a SINGLE SFP+ fiber cable has two runs, and as such, when I do an fdisk -l on my boxes after doing the appropriate fiber channel zoning and such, I usually end up with two /dev/sdX devices that reflect a SINGLE “virtual disk” on our fiber channel connected SAN appliance (a Dell PowerVault md3600f).

It works, but I figure it’s probably not best practice to simply mount ONE of those to a path. How do I mount them so that I’m appropriately taking advantage of multipathing? I’ve never done this before. :frowning:

2

There’s a package to install and a service to run, device-mapper-multipath and multipathd, I believe. That should get you multipath devices in /dev. If you use user_friendly_names it’ll give you mpatha, b, &c., saving the mappings in /etc/multipath/bindings so they persist across reboots, otherwise you’ll have WWIDs in /dev/mapper. Like the usual guidance about sda, b, c, you’ll want to use the mpath or WWID aliases for mounting instead of the dm- devices so they don’t change out from under you, unless you have LVM or something like that labeling them into persistently-named higher-level devices for you.

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