From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <5be72bbe81113b5bc56098b12d1483bc@quintile.net>
From: "Steve Simon" <steve@quintile.net>
Date: Sun,  3 Aug 2008 22:14:54 +0100
To: 9fans@9fans.net
In-Reply-To: <20080803154627.1DD1F1E8C47@holo.morphisms.net>
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Subject: Re: [9fans] Subject: Venti, redundancy, and hardware failure.
Topicbox-Message-UUID: fa52f41e-ead3-11e9-9d60-3106f5b1d025

> But suppose you are asking "I changed the disk
> device name in venti.conf.  What else do I
> need to do for that to take effect?"
> The answer is nothing:...

having been in this situation, here is what I have planned
to do - but still havent got around to yet ...

I am going to make two new partitions of one sector each
which contain modified copies of the venti config but which specify
only one of the two mirrored disks in my arenas pair.

This, combined with changes to plan9.ini will allow me to have boot options
of venti-mirrored (normal venti partition) venti-sd01 and venti-sd02
which use those named partitions in case one of my physical disks dies;
these options setting the venti= variable differently.

this works because venti is passsed the name of the config file it needs
at startup, by convention this config 'file' is the first few tens of bytes
in the arenas partition (venti leaves the first chunk of its partition empty
for this reason, as does fossil). This however is convention only, its the
config data itself which tells venti where to find its disk partitions.

-Steve