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When I am running ab on my website I get a ton of these responses:

SSL read failed - closing connection
SSL read failed - closing connection
SSL read failed - closing connection

And some times it is successful. I am on a MacBook Pro 10.7.2. What is weird is, someone else does the same test on a very simular machine, not OS Lion, right next to me and has no problems.

Any ideas? I am sure this is something on my machine because I get ab to work all over the place.

The command is simply: ab -c 100 -n 1000

One other thing, when I look in the nginx logs, I do see some requests coming in from the ab so it is working some. And also, the logs do not show the failed ones.

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Your web server logs -- can we see them? At least a relevant chunk from around when you manage to get this error? (is an SSL error being reported by the server or just the client?) – voretaq7 Jan 5 '12 at 21:41
MYIP - - [05/Jan/2012:16:42:07 -0500] "GET /MYURL HTTP/1.0" 503 512 "-" "ApacheBench/2.3" MYIP - - [05/Jan/2012:16:42:07 -0500] "GET /MYURL HTTP/1.0" 503 512 "-" "ApacheBench/2.3" – chantheman Jan 5 '12 at 22:08
up vote 6 down vote accepted

Looks like you are encountering a bug in ab for which there is a patch.

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I backup that: brew install ab – jobano Feb 6 '14 at 0:30
Still an issue on Mac OS with self-signed certs and brew install ab – here Jul 29 '15 at 22:15

Question - what happens if you drop the concurrency? The default ulimit on Lion is quite low - 256 if memory serves me and you may be running into that here. If dropping the concurrency sorts it out, just up your ulimit and try again:

ulimit -a (to list); ulimit -n 1024 (or whatever number you wish) to increase it.

Good explanation of it here:

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