[OpenAFS] openafs high availability problem

Derrick Brashear shadow@gmail.com
Wed, 29 Aug 2007 07:53:35 -0400


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On 8/29/07, Sophana <sophana@zizi.ath.cx> wrote:
>
> Hi
>
> Still testing openafs features.
>
> I have 2 master servers in my listed in /usr/vice/etc/CellServDb
> So all services are replicated, including root volumes and some more.
>
> Both my servers are listed in bos listhost XXX
>
> Now I shutdown one of the master servers.
> What I get is that my whole afs cell is frozen during 1 minute.


Not exactly.

After 1 minute, the client switches to the other servers.


If a client is timing out a server it takes a little under a minute. There's
no guarantee the client will be using that server, so it might take zero.

Why does it take so long to switch between master servers?
>
> Is there a tweak to make this faster? 5seconds or less would be better.


I can give you a patch to do that, if you ever use AFS in a higher latency
scenario of course I wouldn't recommend it.

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<br><br><div><span class="gmail_quote">On 8/29/07, <b class="gmail_sendername">Sophana</b> &lt;<a href="mailto:sophana@zizi.ath.cx">sophana@zizi.ath.cx</a>&gt; wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Hi<br><br>Still testing openafs features.<br><br>I have 2 master servers in my listed in /usr/vice/etc/CellServDb<br>So all services are replicated, including root volumes and some more.<br><br>Both my servers are listed in bos listhost XXX
<br><br>Now I shutdown one of the master servers.<br>What I get is that my whole afs cell is frozen during 1 minute.</blockquote><div><br>Not exactly. <br></div><br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
After 1 minute, the client switches to the other servers.</blockquote><div><br>If a client is timing out a server it takes a little under a minute. There&#39;s no guarantee the client will be using that server, so it might take zero.
<br></div><br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">Why does it take so long to switch between master servers?<br><br>Is there a tweak to make this faster? 5seconds or less would be better.
</blockquote><div><br>I can give you a patch to do that, if you ever use AFS in a higher latency scenario of course I wouldn&#39;t recommend it.<br>&nbsp;</div><br></div><br>

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