Silent Post Not Working? Check your SSL

shushry — Tue, 13 Aug 2013 16:30:28 GMT

We recently had a case of our silent post reception suddenly disappearing, and I wanted to share the experience here in case this helps others.

Since all modern browsers now support the SNI specification, where you can now host multiple SSL sites under a single IP address (Name-based virtual hosts using a single IP) this presents the possibility of not only using a single IP but also SSL certificates that can support multiple domains.

We recently updated our hosting to take advantage of this, and all modern browsers support it. However, we discovered that the Authorize.net Silent Post feature is sensitive to any kind of problem with your SSL certificate if your URL is an https (ssl) one, and will silently FAIL - you won't get any activity in your log to indicate that Auth.net TRIED to communicate with your silent post URL, and Auth.net will not have any indictation either. Problems that could cause this are a self-signed SSL certificate, expried cert, non-matching cert, etc (classic issues) - but it looks like any kind of SNI support is also missing from Auth.net's Silent Post technology. Whatever tool (curl?) is being used, doesn't support SNI, as once we eliminated this from the equation, we began receiving our posts again.

Workarounds:

1) Provide a non-ssl silent post URL, if possible, or

2) Use non-SNI technology (i.e., dedicated IP and single-domain cert) for your website, until Auth.net updates their code to support SNI.

Re: Silent Post Not Working? Check your SSL

iBotPeaches — Tue, 13 Aug 2013 21:02:48 GMT

http://community.developer.authorize.net/t5/Integration-and-Testing/Silent-Post-URL-Not-Working/td-p/34045

Yep, a few weeks ago I was in your boat. Was quite a bit of maddening debugging till I found out it was SNI not being supported.

Re: Silent Post Not Working? Check your SSL

marisad — Wed, 14 Aug 2013 16:11:20 GMT

I am having a similar problem. My Silent post URL stopped working on or around 8/3. It was not using SSL. Any ideas?

topic Re: Silent Post Not Working? Check your SSL in Integration and Testing

Silent Post Not Working? Check your SSL

Re: Silent Post Not Working? Check your SSL

Re: Silent Post Not Working? Check your SSL