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general discussion of cosign development and deployment
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Re: replication behind load balancer
On 24 Mar 2005, at 10:46, johanna bromberg craig wrote:
Also, as a side note, I'm not sure fail over in the clients will
work right if both cosign servers are behind a load balancer. I
haven't drawn it all out yet, but the basic idea behind client fail
over is that the filters ask every weblogin server they are aware
of ( A, B, and C ) based on the lookup they did at startup. If they
are talking to a load balancer that only had 1 IP/name, they might
only get A when in fact B happen to have the most up-to-date
information. Like I said, I haven't really thought about this
though, so I might be wrong, too.
You're correct. My suggested configuration would be to have the load
balancer only handle HTTP(S) traffic. In order for filter <->
cosignd interactions (include replication and fail over) to function
properly, the filters need to have direct access to each of the
On 24 Mar 2005, at 14:20, Brian Hatch wrote:
Here's a horrible thought: does the filter try each returned A
sequence, without eliminating duplicates?
How often does it check the DNS name weblogin.example.com, by the way?
The apache and IIS filters only looks up the server address(es) at
restart, not sure what Java CoSign does. Duplicates are not
suppressed, and DNS order is maintained. Filters are expected to
cache and reuse connections to cosignd. Most filter connections to
cosignd are relatively long lived (minutes, hours). Idle connections
are timed out by cosignd.