Balancer Algorithms

[Philipp Michels]

Stephen Nelson-Smith schrieb:
> Hello,
> 
> I want to distribute traffic across backend servers based purely on
> *availability*.
> 
> I don't want to send some traffic to one which is less busy, or has
> less traffic, , or has fewer connections, I want to send traffic to a
> second node only if the first node is unavailable.
> 
> How can I do this?
> 
> S.
> 

take a look at http://wiki.codemongers.com/NginxHttpUpstreamModule

the section "server" describes some options, e.g.

--snip--

backup - (0.6.7 or later) only uses this server if the non-backup
servers are all down or busy

--snap--

so this should work:

upstream  backend  {
    server   backend1.example.com;
    server   backend2.example.com backup;
}

kind regards

Philipp

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Dipl.-Inf. Philipp Michels
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