unicorn Ruby/Rack server user+dev discussion/patches/pulls/bugs/help
 help / color / mirror / code / Atom feed
From: Eric Wong <normalperson@yhbt.net>
To: unicorn list <mongrel-unicorn@rubyforge.org>
Subject: Re: Unicorn and HAProxy, 500 Internal errors after checks
Date: Thu, 2 Dec 2010 17:39:59 +0000	[thread overview]
Message-ID: <20101202173959.GA24132@dcvr.yhbt.net> (raw)
In-Reply-To: <AANLkTimHCSGv9c-a9y+zN42_Gf+csTHQ+e5wh8OvKib9@mail.gmail.com>

Pierre <oct@fotopedia.com> wrote:
> On Wed, Dec 1, 2010 at 8:58 PM, Eric Wong <normalperson@yhbt.net> wrote:
> > I'm not sure how Unicorn is actually replying to anything, does HAProxy
> > write *anything* to the socket?
> 
> It does. To reproduce the behavior, start a unicorn, start a sniffing
> tool (ngrep for example), connect to the unicorn and disconnect
> immediately:
> 
> Connecting endpoint:
> 
> [08:22][virtual] root@infrabox:~# telnet localhost 2002
> Trying 127.0.0.1...
> Connected to infrabox.virtual.ftnz.net.
> Escape character is '^]'.
> ^]
> telnet> quit
> Connection closed.

Hi, you started writing an HTTP message ("quit" can be a valid HTTP
method name) and disconnected; don't do that.

> Further packet inspection reveals that the 500 Internal Server Error
> is sent after the telnet has sent a FIN packet which means it will
> just be discarded. I understand logging it could be a DoS vector, but
> you must admit that seing 500's from the server without any obvious
> reason can be frightening at first.

You can enable Ruby debugging (pass '-d' to unicorn) to see exactly
which exception you got.  Really, it shouldn't matter, you should be
sending real HTTP requests for health checks.

-- 
Eric Wong
_______________________________________________
Unicorn mailing list - mongrel-unicorn@rubyforge.org
http://rubyforge.org/mailman/listinfo/mongrel-unicorn
Do not quote signatures (like this one) or top post when replying


  reply	other threads:[~2010-12-02 17:46 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-12-01 11:59 Unicorn and HAProxy, 500 Internal errors after checks Pierre
2010-12-01 16:12 ` Clifton King
2010-12-01 17:02   ` Pierre
2010-12-01 16:52 ` Eric Wong
2010-12-01 17:14   ` Pierre
2010-12-01 19:58     ` Eric Wong
2010-12-02  0:42       ` Lawrence Pit
2010-12-02  4:59         ` Eric Wong
2010-12-02  8:38       ` Pierre
2010-12-02 17:39         ` Eric Wong [this message]
2010-12-03  8:41           ` Pierre
2010-12-04 23:38             ` Eric Wong
2010-12-05  1:04               ` russell muetzelfeldt
2010-12-06 18:39                 ` Eric Wong
2010-12-02 17:41     ` Eric Wong

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

  List information: https://yhbt.net/unicorn/

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20101202173959.GA24132@dcvr.yhbt.net \
    --to=normalperson@yhbt.net \
    --cc=mongrel-unicorn@rubyforge.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
Code repositories for project(s) associated with this public inbox

	https://yhbt.net/unicorn.git/

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).