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SailFin at JavaOne

Tomorrow (Wednesday) morning at 9.30am, me and Kristoffer talk about SailFin architecture. The Venue is Hall E 134. This session gives the details about the project architecture, features and roadmap. Kristoffer and Ola have another session on Friday at 12.10 about End to End Communication Services with Java ME and Java EE. This is at Esplanade 303.

There is a hands on lab that demonstrates how to develop applications on SailFin. This is at 9.30am on Thursday at Hall E 130/131.

Then there is another hands on lab that shows performance analysis of SIP applications. This is at 1.00pm on Thursday, again at Hall E 130/131.

Many developers and architects from Sun and Ericsson are available in the SailFin booth in the Pavilion. Please do come and meet us!

FInally.... There is a Sun-Ericsson Application Competition that is launched this week. Please participate to win $5000 or a Sony Ericsson Phone.

GlassFish and Windows Firewall

One of my Sun collegues (Bobby) noticed that glassfish web server stops responding soon after the startup. The most interesting thing he found was that he can access the webserver using http://localhost:8080 where as accessing it using IP address (http://x.x.x.x:8080) wasnt working. The plot thickened when we found that the webserver can be accessed once using the IP address and from second time onwards it started failing. Two web browsers and a wget.exe showed the same behaviour.

Bobby is located in Santa Clara and I am located in Bangalore office of Sun Microsystems. Bobby setup a VNC Server on the laptop during his night so that I can look at whats happening during my day. Global engineering certainly certainly has advantages :-)

Debugging spell was quite longer than usual. Finally, we found that the issue was because of a firewall setting in the norton windows firewall.

As explained here symantec firewall has a setting called "Default Inbound loopback" which is configured to allow only 127.0.0.1. When this configuration is changed to allow any IP address (well bobby was using DHCP) the server started working.

This is not the first firewall related issue glassfish team has faced. Another one is with the Windows java.nio Selector implementation. Windows selector implementation in JDK use a loopback socket to handle the wakeup mechanism. But some firewalls are particularly strict against loopback sockets. Typically the issue will surface with the following stacktrace

java.io.IOException: Unable to establish loopback connection
at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:106)
at java.security.AccessController.doPrivileged(Native Method)
at sun.nio.ch.PipeImpl.(PipeImpl.java:122)
at sun.nio.ch.SelectorProviderImpl.openPipe(SelectorProviderImpl.java:27)

There are so many reports about this issue. Here are some links where people faced it outside glassfish [apache, limeware]

A neat explanation about this issue can be found in this sun forum link on socket programming.

Thats all for today. Now that I have started working from home for 2 days a week, hopefully I will get time to write next blog soon.

Thanks to Bobby for his excellent support on debugging some of these issues.

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