Storage 'failover' largely kills FreeBSD 10.x under XenServer?

[Karl Pielorz]

--On 21 September 2017 14:04 +0200 rainer at ultra-secure.de wrote:

> I asked myself already if the disks from Xen(Server) are really CAM-disks.
>
> They certainly don't show up with camcontrol devlist.

So they don't. I presumed they were cam, as they're presented as 'ada0'.

> If they don't show-up there, why should any cam timeouts apply?

It appears they don't :) (at least, so far).

> BTW: storage-failures also kill various Linux hosts.
> They usually turn their filesystem into read-only mode and then you've
> got to reboot anyway.

Yes, I know - it's a bit of an upheaval to cope with storage fail over - 
annoyingly the windows boxes (though they go 'comatose' while it's 
happening) all seem to survive.

I could cope with a few VM's rebooting - but to see so many just fold and 
panic, adds a lot of "insult to injury" at fail over time :(

[And I know, if I/O is unavailable you're going to be queuing up a whole 
'world of pain' anyway for when it returns, such as listen queues, pending 
disk I/O, hung processes waiting for I/O etc. etc.) - but to have a 
fighting chance of unwinding it all when I/O recovers - would be good.

-Karl