[undertow-dev] occasional 502 from Apache HTTP Proxy
Edgar Espina
espina.edgar at gmail.com
Thu Jan 22 11:18:25 EST 2015
we put nginx upfront undertow and everything works as expected.
so we have: apache -> nginx -> undertow :S
apache can't be removed it and as I said before existing apps running on
Tomcat/Jetty work without any issue
we need to move on with our project (wasted a lot of time on this) but I
will try capture the traffic with wireshark and shared it.
still, if you find out something will be helpful too.
On Wed, Jan 21, 2015 at 4:51 PM, Jason Greene <jason.greene at redhat.com>
wrote:
> Would you be willing to capture the traffic with wireshark or (tcpdump
> using -s 65535) when the failure occurs? It would be helpful in diagnosing
> the exact reason the connection is lost (tcp, http protocol issue, etc).
>
> If you prefer not to post the dump on list, you can email us privately.
>
> Thanks!
>
>
> > On Jan 21, 2015, at 1:40 PM, Edgar Espina <espina.edgar at gmail.com>
> wrote:
> >
> > Nope, it doesn't help.
> >
> > Stuart, you mentioned that:
> > "For a normal graceful close Undertow should be sending Connection:close
> headers."
> >
> > Is it mean that on a req/res cycle, Undertow should always set the
> Connection response header with close or keep-alive?
> >
> > Thanks
> >
> >
> >
> >
> > On Tue, Jan 20, 2015 at 5:07 PM, Stuart Douglas <sdouglas at redhat.com>
> wrote:
> >
> >
> > ----- Original Message -----
> > > From: "Edgar Espina" <espina.edgar at gmail.com>
> > > To: "Tomaž Cerar" <tomaz.cerar at gmail.com>
> > > Cc: "Stuart Douglas" <sdouglas at redhat.com>,
> undertow-dev at lists.jboss.org
> > > Sent: Wednesday, 21 January, 2015 2:03:10 AM
> > > Subject: Re: [undertow-dev] occasional 502 from Apache HTTP Proxy
> > >
> > > seems to be some sort of timeout, because everything work as expected,
> but
> > > then after waiting for a while and got again the 502.
> >
> > That is odd, as there is no timeout configured. What does your network
> config between the LB and Undertow look like?
> >
> > Does enabling TCP keep alive (Options.KEEP_ALIVE) help?
> >
> > Stuart
> >
> >
> > >
> > > also, I did set the content-length for static resources and call
> > > .endExchange after a 304 response, set a backlog of 1000 and 10000
> too. But
> > > it didn't help.
> > >
> > >
> > >
> > > On Mon, Jan 19, 2015 at 9:57 AM, Tomaž Cerar <tomaz.cerar at gmail.com>
> wrote:
> > >
> > > > Maybe related to
> > > >
> http://stackoverflow.com/questions/169453/bad-gateway-502-error-with-apache-mod-proxy-and-tomcat
> > > >
> > > > or
> > > >
> http://qnalist.com/questions/4502641/users-httpd-mod-proxy-ignores-incompleteness-of-chunked-coding-response-from-backend
> > > >
> > > > On Mon, Jan 19, 2015 at 1:33 PM, Edgar Espina <
> espina.edgar at gmail.com>
> > > > wrote:
> > > >
> > > >> Sure, it is 2.2.15.
> > > >>
> > > >>
> > > >>
> > > >> On Mon, Jan 19, 2015 at 9:29 AM, Tomaž Cerar <tomaz.cerar at gmail.com
> >
> > > >> wrote:
> > > >>
> > > >>> Edgar,
> > > >>>
> > > >>> what is the version of Apache and mod_proxy module you are using.
> > > >>> maybe it will be easier to reproduce with exact version you have..
> > > >>>
> > > >>> --
> > > >>> tomaz
> > > >>>
> > > >>> On Mon, Jan 19, 2015 at 1:15 PM, Edgar Espina <
> espina.edgar at gmail.com>
> > > >>> wrote:
> > > >>>
> > > >>>> The source code can be found here:
> > > >>>> https://github.com/jooby-project/jooby
> > > >>>>
> > > >>>> Undertow related classes are here:
> > > >>>>
> https://github.com/jooby-project/jooby/tree/master/jooby/src/main/java/org/jooby/internal/undertow
> > > >>>> .
> > > >>>> Server is built here:
> > > >>>>
> https://github.com/jooby-project/jooby/blob/master/jooby/src/main/java/org/jooby/internal/undertow/UndertowServer.java
> > > >>>> Response is sent here:
> > > >>>>
> https://github.com/jooby-project/jooby/blob/master/jooby/src/main/java/org/jooby/internal/undertow/UndertowResponse.java#L336-382
> > > >>>>
> > > >>>> My microweb-framework was built on top of Jetty, so for now I
> used the
> > > >>>> blocking API and follow more or less what we usually do with
> Servlets
> > > >>>> (acquire an outstream).
> > > >>>>
> > > >>>> I will review what I'm doing and try to figure it out what is
> going on
> > > >>>> too.
> > > >>>>
> > > >>>> Thanks for your help, Stuart.
> > > >>>>
> > > >>>>
> > > >>>>
> > > >>>>
> > > >>>> On Mon, Jan 19, 2015 at 2:12 AM, Stuart Douglas <
> sdouglas at redhat.com>
> > > >>>> wrote:
> > > >>>>
> > > >>>>> My best guess as to what is happening is that Undertow closing a
> > > >>>>> connection after a request is done for some reason, and the
> apache
> > > >>>>> attempts
> > > >>>>> to re-use this connection without realising that it is dead.
> > > >>>>>
> > > >>>>> In general this should not happen, Undertow should only forcibly
> close
> > > >>>>> a connection if it knows that it is broken (e.g. a content
> length is
> > > >>>>> set
> > > >>>>> and the full amount of content is not written). For a normal
> graceful
> > > >>>>> close
> > > >>>>> Undertow should be sending Connection:close headers.
> > > >>>>>
> > > >>>>> I am going to investigate some more, and see if I can figure out
> what
> > > >>>>> is going on. It seems unlikely but is there any chance your code
> > > >>>>> forcibly
> > > >>>>> closes the ServerConnection (HttpServerExchange.getConnection())
> > > >>>>> because
> > > >>>>> that could potentially cause this issue. Setting the exchange to
> > > >>>>> non-persistent after headers have been sent could also cause it.
> > > >>>>>
> > > >>>>> Stuart
> > > >>>>>
> > > >>>>> ----- Original Message -----
> > > >>>>> > From: "Edgar Espina" <espina.edgar at gmail.com>
> > > >>>>> > To: "Stuart Douglas" <sdouglas at redhat.com>
> > > >>>>> > Cc: undertow-dev at lists.jboss.org
> > > >>>>> > Sent: Monday, 19 January, 2015 2:53:06 PM
> > > >>>>> > Subject: Re: [undertow-dev] occasional 502 from Apache HTTP
> Proxy
> > > >>>>> >
> > > >>>>> > Done, but makes no difference. Still got the 502 random errors
> :S
> > > >>>>> >
> > > >>>>> > On Sun, Jan 18, 2015 at 11:13 PM, Stuart Douglas <
> > > >>>>> sdouglas at redhat.com>
> > > >>>>> > wrote:
> > > >>>>> >
> > > >>>>> > > I had a play around with apache locally, and I could
> reproduce
> > > >>>>> this in
> > > >>>>> > > some circumstances, and it looks like we are not setting a
> high
> > > >>>>> enough
> > > >>>>> > > backlog by default.
> > > >>>>> > >
> > > >>>>> > > Can you try adding:
> > > >>>>> > >
> > > >>>>> > > undertow.setSocketOption(Options.BACKLOG, 1000)
> > > >>>>> > >
> > > >>>>> > > To your Undertow builder? I am going to increase this in our
> > > >>>>> default
> > > >>>>> > > config upstream.
> > > >>>>> > >
> > > >>>>> > > Hopefully this is the issue that you are running into.
> > > >>>>> > >
> > > >>>>> > > Stuart
> > > >>>>> > >
> > > >>>>> > >
> > > >>>>> > > ----- Original Message -----
> > > >>>>> > > > From: "Edgar Espina" <espina.edgar at gmail.com>
> > > >>>>> > > > To: "Stuart Douglas" <sdouglas at redhat.com>
> > > >>>>> > > > Cc: undertow-dev at lists.jboss.org
> > > >>>>> > > > Sent: Monday, 19 January, 2015 12:10:16 PM
> > > >>>>> > > > Subject: Re: [undertow-dev] occasional 502 from Apache
> HTTP Proxy
> > > >>>>> > > >
> > > >>>>> > > > It is a default undertow instance with a HTTP listener,
> just set
> > > >>>>> work
> > > >>>>> > > > threads to 200. Is there a default idle timeout? I can'
> tell
> > > >>>>> from javadoc
> > > >>>>> > > > and looking at the code.
> > > >>>>> > > >
> > > >>>>> > > >
> > > >>>>> > > > On Sun, Jan 18, 2015 at 9:59 PM, Stuart Douglas <
> > > >>>>> sdouglas at redhat.com>
> > > >>>>> > > wrote:
> > > >>>>> > > >
> > > >>>>> > > > >
> > > >>>>> > > > >
> > > >>>>> > > > > Edgar Espina wrote:
> > > >>>>> > > > >
> > > >>>>> > > > >> I'm not, channel does it.
> > > >>>>> > > > >>
> > > >>>>> > > > >> Problem is present on both. For example, home page has a
> > > >>>>> > > content-length
> > > >>>>> > > > >> header but jquery.js use chunked.
> > > >>>>> > > > >>
> > > >>>>> > > > >
> > > >>>>> > > > > In general if you are serving static resources you are
> better
> > > >>>>> off
> > > >>>>> > > setting
> > > >>>>> > > > > the content length (slightly more efficient, and the
> browser
> > > >>>>> can
> > > >>>>> > > display
> > > >>>>> > > > > progress on downloads).
> > > >>>>> > > > >
> > > >>>>> > > > >
> > > >>>>> > > > >> Do I have to call .endExchange? or closing the output
> stream
> > > >>>>> is
> > > >>>>> > > enough?
> > > >>>>> > > > >>
> > > >>>>> > > > >
> > > >>>>> > > > > Closing the output stream is enough. endExchange is
> > > >>>>> automatically
> > > >>>>> > > called
> > > >>>>> > > > > once the call stack returns anyway, unless you have
> dispatched
> > > >>>>> the
> > > >>>>> > > exchange
> > > >>>>> > > > > or started async IO.
> > > >>>>> > > > >
> > > >>>>> > > > > The 'connection reset by peer' error in the apache log
> while
> > > >>>>> reading
> > > >>>>> > > the
> > > >>>>> > > > > status like kinda indicates that the request does not
> even get
> > > >>>>> to this
> > > >>>>> > > > > point anyway, and the underlying TCP connection is
> probably
> > > >>>>> being torn
> > > >>>>> > > down
> > > >>>>> > > > > somehow.
> > > >>>>> > > > >
> > > >>>>> > > > > Do you have any kind of timeouts set? If you have an idle
> > > >>>>> timeout set
> > > >>>>> > > on
> > > >>>>> > > > > the listener there is a race where Undertow can close the
> > > >>>>> channel due
> > > >>>>> > > to
> > > >>>>> > > > > inactivity just as the front end starts to send a
> request.
> > > >>>>> > > > >
> > > >>>>> > > > > Stuart
> > > >>>>> > > > >
> > > >>>>> > > > >
> > > >>>>> > > > >> Thanks
> > > >>>>> > > > >>
> > > >>>>> > > > >> On Sun, Jan 18, 2015 at 9:48 PM, Stuart Douglas <
> > > >>>>> sdouglas at redhat.com
> > > >>>>> > > > >> <mailto:sdouglas at redhat.com>> wrote:
> > > >>>>> > > > >>
> > > >>>>> > > > >> Another question, are you setting a content length
> on the
> > > >>>>> > > responses?
> > > >>>>> > > > >> If not the channel will automatically set one if the
> > > >>>>> response fits
> > > >>>>> > > > >> inside a buffer, otherwise chunked encoding will be
> used.
> > > >>>>> > > > >>
> > > >>>>> > > > >> It might be helpful to know if this only happens on
> > > >>>>> chunked, fixed
> > > >>>>> > > > >> length or both.
> > > >>>>> > > > >>
> > > >>>>> > > > >> Stuart
> > > >>>>> > > > >>
> > > >>>>> > > > >> Edgar Espina wrote:
> > > >>>>> > > > >>
> > > >>>>> > > > >> latest: 1.2.0.Beta8
> > > >>>>> > > > >>
> > > >>>>> > > > >> On Sun, Jan 18, 2015 at 9:42 PM, Stuart Douglas
> > > >>>>> > > > >> <sdouglas at redhat.com <mailto:
> sdouglas at redhat.com>
> > > >>>>> > > > >> <mailto:sdouglas at redhat.com <mailto:
> > > >>>>> sdouglas at redhat.com>>>
> > > >>>>> > > wrote:
> > > >>>>> > > > >>
> > > >>>>> > > > >> Also what version of Undertow are you
> using?
> > > >>>>> > > > >>
> > > >>>>> > > > >> Stuart
> > > >>>>> > > > >>
> > > >>>>> > > > >> ----- Original Message -----
> > > >>>>> > > > >> > From: "Edgar Espina" <
> espina.edgar at gmail.com
> > > >>>>> > > > >> <mailto:espina.edgar at gmail.com>
> > > >>>>> > > > >> <mailto:espina.edgar at gmail.com <mailto:
> > > >>>>> espina.edgar at gmail.com
> > > >>>>> > > > >> >__>>
> > > >>>>> > > > >> > To: "Stuart Douglas" <sdouglas at redhat.com
> > > >>>>> > > > >> <mailto:sdouglas at redhat.com>
> > > >>>>> > > > >> <mailto:sdouglas at redhat.com <mailto:
> > > >>>>> sdouglas at redhat.com>>>
> > > >>>>> > > > >> > Cc: undertow-dev at lists.jboss.org
> > > >>>>> > > > >> <mailto:undertow-dev at lists.jboss.org>
> > > >>>>> > > > >> <mailto:undertow-dev at lists.__jboss.org
> > > >>>>> > > > >> <mailto:undertow-dev at lists.jboss.org>>
> > > >>>>> > > > >> > Sent: Monday, 19 January, 2015 11:13:21 AM
> > > >>>>> > > > >> > Subject: Re: [undertow-dev] occasional 502
> from
> > > >>>>> Apache HTTP
> > > >>>>> > > > >> Proxy
> > > >>>>> > > > >> >
> > > >>>>> > > > >> > found this in apache:
> > > >>>>> > > > >> >
> > > >>>>> > > > >> > (104) Connection reset by peer: proxy: error
> > > >>>>> reading status
> > > >>>>> > > > >> line from
> > > >>>>> > > > >> > remote server
> > > >>>>> > > > >> >
> > > >>>>> > > > >> > but nothing in undertow.
> > > >>>>> > > > >> >
> > > >>>>> > > > >> > got 502 on HTTP GET. Sometimes while calling
> the
> > > >>>>> home page
> > > >>>>> > > / or
> > > >>>>> > > > >> when page
> > > >>>>> > > > >> > loads OK, got 502 on page resources (js, css,
> > > >>>>> images).
> > > >>>>> > > > >> >
> > > >>>>> > > > >> > I call startBlocking and use the
> outputstream to
> > > >>>>> write the
> > > >>>>> > > > >> response, when
> > > >>>>> > > > >> > everything has been written I call the
> > > >>>>> "outputstream.close"
> > > >>>>> > > > >> method. Do I
> > > >>>>> > > > >> > need to call exchange.endExchange too?
> > > >>>>> > > > >> >
> > > >>>>> > > > >> > Thanks
> > > >>>>> > > > >> >
> > > >>>>> > > > >> > On Sun, Jan 18, 2015 at 8:52 PM, Stuart
> Douglas
> > > >>>>> > > > >> <sdouglas at redhat.com <mailto:
> sdouglas at redhat.com>
> > > >>>>> > > > >> <mailto:sdouglas at redhat.com <mailto:
> > > >>>>> sdouglas at redhat.com>>>
> > > >>>>> > > wrote:
> > > >>>>> > > > >> >
> > > >>>>> > > > >> > > Is there any info in the log? Or is there
> any
> > > >>>>> specific
> > > >>>>> > > type
> > > >>>>> > > > >> of
> > > >>>>> > > > >> request
> > > >>>>> > > > >> > > that causes this?
> > > >>>>> > > > >> > >
> > > >>>>> > > > >> > > Stuart
> > > >>>>> > > > >> > >
> > > >>>>> > > > >> > >
> > > >>>>> > > > >> > > ----- Original Message -----
> > > >>>>> > > > >> > > > From: "Edgar Espina" <
> espina.edgar at gmail.com
> > > >>>>> > > > >> <mailto:espina.edgar at gmail.com>
> > > >>>>> > > > >> <mailto:espina.edgar at gmail.com <mailto:
> > > >>>>> espina.edgar at gmail.com
> > > >>>>> > > > >> >__>>
> > > >>>>> > > > >> > > > To: undertow-dev at lists.jboss.org
> > > >>>>> > > > >> <mailto:undertow-dev at lists.jboss.org>
> > > >>>>> > > > >> <mailto:undertow-dev at lists.__jboss.org
> > > >>>>> > > > >> <mailto:undertow-dev at lists.jboss.org>>
> > > >>>>> > > > >> > > > Sent: Monday, 19 January, 2015 9:42:19 AM
> > > >>>>> > > > >> > > > Subject: [undertow-dev] occasional 502
> from
> > > >>>>> Apache HTTP
> > > >>>>> > > > >> Proxy
> > > >>>>> > > > >> > > >
> > > >>>>> > > > >> > > > Hi,
> > > >>>>> > > > >> > > >
> > > >>>>> > > > >> > > > I've an Undertow application behind
> apache
> > > >>>>> reverse
> > > >>>>> > > proxy,
> > > >>>>> > > > >> trying to load
> > > >>>>> > > > >> > > a
> > > >>>>> > > > >> > > > page displays error 502 proxy error.
> > > >>>>> > > > >> > > >
> > > >>>>> > > > >> > > > Still couldn't find why so I wonder if
> any of
> > > >>>>> you find
> > > >>>>> > > a
> > > >>>>> > > > >> similar problem
> > > >>>>> > > > >> > > with
> > > >>>>> > > > >> > > > Undertow and Apache.
> > > >>>>> > > > >> > > >
> > > >>>>> > > > >> > > > Please note this is our first app on top
> of
> > > >>>>> Undertow,
> > > >>>>> > > > >> existing apps
> > > >>>>> > > > >> > > running
> > > >>>>> > > > >> > > > on Tomcat/Jetty are OK.
> > > >>>>> > > > >> > > >
> > > >>>>> > > > >> > > > Appreciate any help.
> > > >>>>> > > > >> > > >
> > > >>>>> > > > >> > > > Thanks
> > > >>>>> > > > >> > > >
> > > >>>>> > > > >> > > > --
> > > >>>>> > > > >> > > > edgar
> > > >>>>> > > > >> > > >
> > > >>>>> > > > >> > > >
> > > >>>>> _________________________________________________
> > > >>>>> > > > >> > > > undertow-dev mailing list
> > > >>>>> > > > >> > > > undertow-dev at lists.jboss.org
> > > >>>>> > > > >> <mailto:undertow-dev at lists.jboss.org>
> > > >>>>> > > > >> <mailto:undertow-dev at lists.__jboss.org
> > > >>>>> > > > >> <mailto:undertow-dev at lists.jboss.org>>
> > > >>>>> > > > >> > > >
> > > >>>>> > > https://lists.jboss.org/__mailman/listinfo/undertow-dev
> > > >>>>> > > > >> <
> > > >>>>> https://lists.jboss.org/mailman/listinfo/undertow-dev>
> > > >>>>> > > > >> > >
> > > >>>>> > > > >> >
> > > >>>>> > > > >> >
> > > >>>>> > > > >> >
> > > >>>>> > > > >> > --
> > > >>>>> > > > >> > edgar
> > > >>>>> > > > >> >
> > > >>>>> > > > >>
> > > >>>>> > > > >>
> > > >>>>> > > > >>
> > > >>>>> > > > >>
> > > >>>>> > > > >> --
> > > >>>>> > > > >> edgar
> > > >>>>> > > > >>
> > > >>>>> > > > >>
> > > >>>>> > > > >>
> > > >>>>> > > > >>
> > > >>>>> > > > >> --
> > > >>>>> > > > >> edgar
> > > >>>>> > > > >>
> > > >>>>> > > > >
> > > >>>>> > > >
> > > >>>>> > > >
> > > >>>>> > > > --
> > > >>>>> > > > edgar
> > > >>>>> > > >
> > > >>>>> > >
> > > >>>>> >
> > > >>>>> >
> > > >>>>> >
> > > >>>>> > --
> > > >>>>> > edgar
> > > >>>>> >
> > > >>>>>
> > > >>>>
> > > >>>>
> > > >>>>
> > > >>>> --
> > > >>>> edgar
> > > >>>>
> > > >>>> _______________________________________________
> > > >>>> undertow-dev mailing list
> > > >>>> undertow-dev at lists.jboss.org
> > > >>>> https://lists.jboss.org/mailman/listinfo/undertow-dev
> > > >>>>
> > > >>>
> > > >>>
> > > >>
> > > >>
> > > >> --
> > > >> edgar
> > > >>
> > > >
> > > >
> > >
> > >
> > > --
> > > edgar
> > >
> >
> >
> >
> > --
> > edgar
> > _______________________________________________
> > undertow-dev mailing list
> > undertow-dev at lists.jboss.org
> > https://lists.jboss.org/mailman/listinfo/undertow-dev
>
> --
> Jason T. Greene
> WildFly Lead / JBoss EAP Platform Architect
> JBoss, a division of Red Hat
>
>
--
edgar
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.jboss.org/pipermail/undertow-dev/attachments/20150122/c9bf6930/attachment-0001.html
More information about the undertow-dev
mailing list