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Subject: Re: ZFS High-Availability NAS
To: freebsd-fs@freebsd.org
References: <20180119151919.GF507@mordor.lan>
From: Jan Bramkamp <crest@rlwinm.de>
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Date: Mon, 22 Jan 2018 11:24:05 +0100
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On 19.01.18 16:19, Julien Cigar wrote:
> Hello,
> 
> I'm wondering if someone has already put in production something
> similar to https://github.com/ewwhite/zfs-ha/wiki (with two HBAs and
> two disk shelves in two chains) with ZFS, gmultipath, and NFS on top ?

I tried to build something similar, but ran into problems with 
gmultipath. There are situtations in which gmultipath retries an I/O 
request ad infinitum, because it can't tell the difference between 
temporary errors (e.g. a link failure) and permanent errors (e.g. a head 
crash). It just sees that the struct bio contains an error and retries 
reactivating failed links if it runs out of active links.

Other than that it it worked ;-).