tomcat-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Agnieszka Allstar <allstar...@gmail.com>
Subject Re: mod_jk recovery when tomcat killed
Date Mon, 30 Apr 2012 16:48:54 GMT
2012/4/30 Christopher Schultz <chris@christopherschultz.net>

> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Kate,
>
> On 4/30/12 7:06 AM, Agnieszka Allstar wrote:
> > Here's my test scenario: 1. Web service client sends SOAP request
> > to apache server. This client sends requests in 2 flavors, either
> > it is a generic SOAP call (A case) or a soap request with some
> > files attached with MTOM (B case). Web service is capable of
> > handling both types of requests. 2. Once the processing starts, I
> > kill this tomcat with "kill -9".
> >
> > The results are: A - when tomcat1 is killed, the request is
> > automatically transmitted to tomcat2. Client receives correct
> > results. This is OK. B - when tomcat1 is killed, the request is not
> > transmitted to tomcat2. Client receives 502 error: bad gateway
> > instead.
>
> Are you using POST to send both messages (A case and B case)?
>

Yes, both are POST.

>
> What if you send a very *small* attachment via MTOM? I'm wondering
> what the real difference is, since in both cases you should be sending
> HTTP POST... the only difference should be larger Content-Length.
>

Good idea, gotta check the small attachment version and see what happens.
I've also noticed that requests differ in Content-Type. For simple soap
request is text/xml and the one with attachments is multipart/related;
type="application/xop+xml (...).

>
> I wonder if mod_jk can only failover the current request (with no
> error to the client) if the request is small enough (or only a small
> amount has already been transferred to the failing server).
>

This could be it I'll check this out. I only need to wait few days until
I'm back in office.

>
> > [Fri Apr 27 12:19:08 2012] [1376450:1] [error]
> > service::jk_lb_worker.c (1425): unrecoverable error 502, request
> > failed. Tomcat failed in the middle of reques [Fri Apr 27 12:19:08
> > 2012] [1376450:1] [error] service::jk_lb_worker.c (1485): All
> > tomcat instances failed, no more workers left
>
> This looks like you have killed both tomcat instances and mod_jk can
> contact neither of them. Are you sure you have gotten mod_jk back in
> communication with both servers between "A case" and "B case" runs? If
> you haven't, this isn't really a valid test.
>

I'm pretty sure there was only one tomcat killed but I'll rerun my tests.
As for initial state, after each test I restart both mod_jk (apache) and
tomcat servers and make sure they appear as ok in mod_jk.

>
> (It looks like some of your mod_jk.log lines have been truncated...
> was that simply a copy/paste error?)
>

You're right thanks.

>
> - -chris
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG/MacGPG2 v2.0.17 (Darwin)
> Comment: GPGTools - http://gpgtools.org
> Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/
>
> iEYEARECAAYFAk+eplQACgkQ9CaO5/Lv0PCDWgCdGiF1xBEIUg3tDfj5bV/HjH+m
> ZkYAoIcFbG7EmdyKm0Jha15HrGOzsC88
> =PQqY
> -----END PGP SIGNATURE-----
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> For additional commands, e-mail: users-help@tomcat.apache.org
>
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message