Hi,

Please see inline.

On Wed, Jul 13, 2016 at 2:24 PM, Natxo Asenjo <natxo.asenjo@gmail.com> wrote:
> So I need to configure multipathd.
>
> I have this /etc/multipath.conf
>
> defaults {
>     user_friendly_names yes
> }

I suggest you consult NetApp's documentation for "host utilities", it
has specific per OS release setting recommendations, IMO, "
user_friendly_names no" is recommended.

>
> #  multipath -ll
> netapp_oracle_datafile (3600a098038303370562b4946426b6743) dm-3 NETAPP,LUN
> C-Mode
> size=350G features='1 queue_if_no_path' hwhandler='0' wp=rw
> |-+- policy='round-robin 0' prio=4 status=active
> | |- 6:0:0:1 sdg 8:96  active ready running
> | `- 3:0:0:1 sdf 8:80  active ready running
> `-+- policy='round-robin 0' prio=1 status=enabled
>   |- 4:0:0:1 sdj 8:144 active ready running
>   `- 5:0:0:1 sdk 8:160 active ready running
> netapp_oracle_recovery (3600a098038303370562b4946426b6742) dm-2 NETAPP,LUN
> C-Mode
> size=300G features='1 queue_if_no_path' hwhandler='0' wp=rw
> |-+- policy='round-robin 0' prio=4 status=active
> | |- 3:0:0:0 sdd 8:48  active ready running
> | `- 6:0:0:0 sde 8:64  active ready running
> `-+- policy='round-robin 0' prio=1 status=enabled
>   |- 5:0:0:0 sdh 8:112 active ready running
>   `- 4:0:0:0 sdi 8:128 active ready running
>

It looks OK .. but if you can provide me with output from "lsblk",
then I can tell you more about it.

It's important that multipathd kernel module + proper multipath.conf
are properly installed into initrd file aka RAM disk. Otherwise the
output above can be different after OS reboots.

> Is this ok? What do I have to use in /etc/fstab?
> /dev/mapper/netapp_oracle_datafile en /dev/mapper/netapp_oracle_recovery? Or
> am I doing something terribly wrong. I called with support but as this is no
> break or fix stuff, they recommend calling professional services ...

NetApp support rocks, right ? =)

Are you planning to employ Linux LVM on top of your multipath device?
If yes, then you need to add those to /etc/fstab.

The best you could do is the following: once you think you've done
everything correctly SAN wise, prior going "production" with it, do
extensive testing, including target (filer) and initiator (your
server) reboots. It will either reveil issues or you are going to see
how awesome it is to have redundancy in place =)