app error: Socket is not connected (Errno::ENOTCONN)

Eric Wong normalperson at
Fri Apr 27 21:15:36 UTC 2012

Matt Smith <matt at> wrote:
> I just tried on a 64-bit Ubuntu 11.10 (kernel 3.0.0-17-generic), ruby
> 1.9.3p0 (2011-10-30 revision 33570) [x86_64-linux]. No issue. Reloaded
> a several pages, many times. No ENOTCONN. Not one. Same app.

OK, thank you for the confirmation.  I wouldn't rule out an occasional
ENOTCONN, though, even if nginx <-> unicorn are on the same LAN.

So I'll still push out my change to ignore Errno::ENOTCONN.  Since it's
highly uncommon in production environments, I'm not concerned about the
performance overhead.

> BSD issue?

It doesn't affect my FreeBSD 9.0 nor Debian/kFreeBSD 6.0 VMs, either.
OSX is non-Free Software, so unicorn cannot officially support it and
performance is irrelevant on it.

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