Hi again.
Don't have the answer yet, but with the help of a professional programmer
friend, I found the trigger. Setting the java.net property
-Djava.net.preferIPv4Stack
fixes it. Now, why the stack got changed, or why it wouldn't work with
IPv6, I don't know yet.
Cheers!
On 1.11.10, Steve White wrote:
> Hello, all,
>
> Further clues to this problem.
>
> It is not a Globus problem per se.
> It is specific to Java programs on this host.
> Other network programs work fine, the simplest Java Socket connection
> fails, with DNS errors.
>
> The traceback showed calls to the Java Socket class, so I wrote a very
> small test code -- see attached. It fails on the problematic system,
> but works on other sytems.
> javac nettest.java
> java nettest your-favourite-hostname
>
> One difference I don't understand is that, although both machines are
> running the same OS (SL 5.5) the strace on the machine that fails shows
> calls mmap2, while on the other it shows calls to mmap. Now, the latter
> is just a wrapper around the former so it shouldn't matter much.
> The failing machine is AMD while the other is an Intel, so maybe that
> accounts for it.
>
> strace output also attached.
>
> Any idea what would cause Java DNS to fail like this, when it is otherwise
> working on a system?
>
> Thanks!
>
> On 29.10.10, Steve White wrote:
> > Further info
> >
> > 1) I think I have eliminated the recent package updates as the source of
> > the problem. I reversed the installs of the perl libraries, as well
> > as some glibc libraries from a previous update, and re-booted with the
> > previous kernel, yet the problem persists.
> >
> > 2) wsrf-query -a -z none -s \
> > https://cashmere.aip.de:8443/wsrf/services/DefaultIndexService
> > Error: ; nested exception is:
> > java.net.UnknownHostException: cashmere.aip.de
> >
> > althogh cashmere is quite reachable from that host otherwise.
> >
> > 3) The problem is in name resolution.
> > Using IP numbers in the above call works.
> > Using the name of the local machine in the above call works.
> >
> > 5) wsrf-query just wrappers this java
> > java -DGLOBUS_LOCATION=/usr/local/globus/gtk
> > -Djava.endorsed.dirs=/usr/local/globus/gtk/endorsed
> > -Djava.security.egd=file:///dev/urandom -classpath
> > /usr/local/globus/gtk/lib/bootstrap.jar:/usr/local/globus/gtk/lib/cog-url.jar:/usr/local/globus/gtk/lib/axis-url.jar
> > org.globus.bootstrap.Bootstrap org.globus.wsrf.client.Query -a -z none -s
> > https://cashmere.aip.de:8443/wsrf/services/DefaultIndexService
> >
> > I ran this under
> > strace -f
> > Not sure what should be there. I see it opening and reading /etc/hosts
> > but nothing that looks like querying DNS... I'm not sure how it goes
> > about that.
> >
> > See attachment (lines with gettimeofday were removed)
> >
> > What should I see?
> >
> > Any ideas now?
> >
> >
> > On 28.10.10, Steve White wrote:
> > > Hi,
> > >
> > > Today we developed a new problem with our WebMDS page:
> > > it now shows no hosts, where several appeared before.
> > >
> > > In the Globus 4.0.8 container.log I see lines like
> > >
> > > 471 WARN impl.AggregatorUtils [ServiceThread-5,detectLoopback:65]
> > > UnknownHostException: cashmere.aip.de
> > > 478 ERROR impl.QueryAggregatorSource [Timer-3,pollGet:122] Exception
> > > Getting Resource Property from
> > > https://cashmere.aip.de:8443/wsrf/services/DefaultIndexService: ; nested
> > > exception is:
> > > java.net.UnknownHostException: cashmere.aip.de
> > >
> > > for each downstream host that previously reported to this host, and for
> > > each upstream host this host reported to.
> > >
> > > However, from the current host, all the servers are quite visible, and
> > > Globus is properly running on them.
> > >
> > > The only clue is, this behaviour started after a system update
> > > (of Scientific Linux 5.5)
> > >
> > > Updated: python26-2.6.5-5.el5.x86_64
> > > Updated: python26-libs-2.6.5-5.el5.x86_64
> > > Installed: kernel-devel-2.6.18-194.17.4.el5.x86_64
> > > Updated: kernel-headers-2.6.18-194.17.4.el5.x86_64
> > > Installed: kernel-2.6.18-194.17.4.el5.x86_64
> > > Updated: perl-NetAddr-IP-4.034-1.el5.rf.x86_64
> > > Updated: perl-DBI-1.615-1.el5.rf.x86_64
> > > Updated: syslinux-4.03-1.el5.rf.x86_64
> > > Updated: perl-Crypt-OpenSSL-RSA-0.26-1.el5.rf.x86_64
> > >
> > > And there you see NetAddr-IP...
> > >
> > > Any ideas?
> > >
> >
> > --
> > | - - - - - - - - - - - - - - - - - - - - - - - - -
> > | Steve White +49(331)7499-202
> > | E-Science Zi. 27 Villa Turbulenz
> > | - - - - - - - - - - - - - - - - - - - - - - - - -
> > | Astrophysikalisches Institut Potsdam (AIP)
> > | An der Sternwarte 16, D-14482 Potsdam
> > |
> > | Vorstand: Prof. Dr. Matthias Steinmetz, Peter A. Stolz
> > |
> > | Stiftung privaten Rechts, Stiftungsverzeichnis Brandenburg: III/7-71-026
> > | - - - - - - - - - - - - - - - - - - - - - - - - -
>
>
>
> --
> | - - - - - - - - - - - - - - - - - - - - - - - - -
> | Steve White +49(331)7499-202
> | E-Science Zi. 27 Villa Turbulenz
> | - - - - - - - - - - - - - - - - - - - - - - - - -
> | Astrophysikalisches Institut Potsdam (AIP)
> | An der Sternwarte 16, D-14482 Potsdam
> |
> | Vorstand: Prof. Dr. Matthias Steinmetz, Peter A. Stolz
> |
> | Stiftung privaten Rechts, Stiftungsverzeichnis Brandenburg: III/7-71-026
> | - - - - - - - - - - - - - - - - - - - - - - - - -
> import java.net.Socket;
>
> public class
> nettest
> {
> public
> nettest( String host )
> {
> try
> {
> Socket si = new Socket( host, 80 );
> System.out.println( "Success connecting to " + host );
> }
> catch( Exception e )
> {
> System.err.println( e.toString() );
> }
> }
> public static void
> main( String [] a )
> {
> if( a.length > 0 )
> {
> nettest bla = new nettest( a[0] );
> }
> else
> {
> System.err.println( "please provide host string" );
> }
> }
> }
--
| - - - - - - - - - - - - - - - - - - - - - - - - -
| Steve White +49(331)7499-202
| E-Science Zi. 27 Villa Turbulenz
| - - - - - - - - - - - - - - - - - - - - - - - - -
| Astrophysikalisches Institut Potsdam (AIP)
| An der Sternwarte 16, D-14482 Potsdam
|
| Vorstand: Prof. Dr. Matthias Steinmetz, Peter A. Stolz
|
| Stiftung privaten Rechts, Stiftungsverzeichnis Brandenburg: III/7-71-026
| - - - - - - - - - - - - - - - - - - - - - - - - -
