[OpenAFS] AFS lag

Felix Frank Felix.Frank@Desy.de
Wed, 18 Mar 2009 22:45:53 +0100 (CET)

>> I agree with Abdelkader and would recommend having at least 3 database
> servers.  You could be walking on very thin ice with just 2.
> Whats the reason for this ?

I'm no ubik engineer, but as far as I understand it, the protocol was not
designed for even numbers of participating servers. For best results, three
or five servers seem to be optimum.

What I definitely whitnessed is that servers in a cell configured with two
servers take more than a minute to elect a sync site after server restarts.
Three servers are supposed to make it in an instant.

Apart from that, my test cell runs two servers and it works just fine, so long
as no DB server restarts are necessary. It's plain annoying when I do
development on a DB service. There may be more pitfalls in 2-server setups
that I'm unaware of.