On 04 May 2014, at 7:26 PM, Dustin Rice <dustin@pdx.edu> wrote:

My guess would be it's failing to validate the SSL certificate. Are you using a self-signed cert? If so, you'll need to import that CA cert across all of your servers.

As I said below, ssldump reveals that the servers are talking successfully to one another, revealing a completely successful SSL handshake. Self signed certs are not being used:

At the same time, ssldump reveals that serverb.example.com and serverc.example.com are successfully speaking to one another, and have a lot to say - data seems to be constantly flowing between them, but not to any successful end.

Regards,
Graham
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