I've been following Australian Open recently and watched the coverage of the semifinal between Murray and Cilic today. At the same time I thought what will happen in the other semifinal between Federer and Tsonga tomorrow.

At this level most of the matches are won by the player psychology. Not by his tennis skills. Sure the skills play a role when the time comes to hit certain trick shot, or to catch a tough ball. But the outcome comes from what happens in players' minds.

All this mental pressure. All these guys being so serious. Is it for the money ? Is it for the glory ? Is it for the victory ? Sure its different for each player but in the end it's just a game.

When I thought about all this a curious question came to my mind.

Hey Roger, what if I give you the tournament prize before it starts ? I would just ask you to play for fun. To show us the best of your bag of tricks.

How do you think, will we enjoy the game more ? Will Federer still be able to win ? ...

java.net.SocketException: Network is unreachable

I hit this about a week ago . First time I saw it was on my office desktop running Debian unstable. Since I was not doing too much Java on it I decided it was a problem with JConsole. I nearly lost a bet out of this:

I was pretty sure JConsole was able to attach to local processes even when they were started without any JMX options enabled. Borislav Tonchev was pretty sure it wasn't. I quickly wrote a Java class with its main method sleeping for 100 seconds and tried to attach to its process. Unfortunately I wasn't able to do so. At that point Borislav walked away with 10 bucks coming out of my pocket.

I was curious enough to check this stuff and at first appeared that Java didn't like the bsdgroups option my ext3 /tmp file system was mounted with. Trying the same thing on my home PC, with bsdgroups disabled showed this java.net.SocketException: Network is unreachable. At this point I was starting to loose ground. I decided to check the docs ( http://java.sun.com/javase/6/docs/technotes/guides/management/jconsole.html ) and they confirmed my point. I checked the documented behavior in a JVM running inside an Windows XP installation I have ( VirtualBox image for the corporate stuff in the office ) and Borislav unhappily brought my money back.

At this point I decided the exception under Debian was caused by a bug in JConsole - probably it was not maintained too much in recent releases as a similar tool appeared - VisualVM.

Several days after this long background, on Saturday, I've also hit the same exception on a production server running Tomcat. Pretty damn strange. I was not able to figure it out immediately. The actual problem was introduced in Debian in the beginning of December last year, with the netbase package setting:

# cat /etc/sysctl.d/bindv6only.conf
net.ipv6.bindv6only=1

This did not showed up on the server immediately, since the netbase upgrade did not apply the new setting. The exception appeared after a restart almost two months after the upgrade.

The workaround is to set the above to "0" as it was before, or to add the option -Djava.net.preferIPv4Stack=true to each Java process you start. I prefer the former as I did not want to configure every Java program (e.g. I use azureus/vuze) manually.

More information could be found in Debian bug #560044

I was unable to access my E-banking at https://e-fibank.bg. It first happened on my Debian unstable box in the office. A few weeks later it also showed on my home PC running Debian testing.

My observations also showed that all the browsers stopped working at once. I'm using Iceweasel (Firefox) for the e-banking itself. Google chrome also showed some weird (unknown) SSL error.

This was enough for me to decide that the problem has been caused by recent package upgrade. I was pretty sure this was caused by the SSL libraries, especially with some recent Bugraq posts about SSL vulnerabilities.

So what I did was:

• remembered when was the last time I successfully used the e-banking
• checked which packages I upgraded recently (only one date showed after the last successful e-banking use - 2010-01-02 )
• looked at browser dependencies ( google-chrome-unstable deps were easier to use since iceweasel is deeply integrated within Debian with many chained dependencies )
• and put the results against each other

So the command I came up with was:

ls -rtl /var/lib/dpkg/info/*.list | \
    grep 2010-01-02 | awk '{print $8}' | \
    cut -d / -f 6 | \
    cut -d . -f 1 | \
    sort | \
    egrep \
       `dpkg -s google-chrome-unstable | \
          grep Depends | \
          tr ',' '\n' | \
          grep '^ ' | \
          awk '{print $1}' | \
          xargs echo | tr ' ' '|'`

So this showed two things only:

libfontconfig1
libnss3-1d

I was not familiar with libnss3 but looking at its package description(SSL related) was enough for me to blame it. So I've checked the aptitude logs:

# grep libnss /var/log/aptitude
[UPGRADE] libnss3-1d 3.12.4-1 -> 3.12.5-1

and have seen which was the older version I used. Then checked /var/cache/apt/archives and it was just sitting there waiting to be restored:

dpkg -i /var/cache/apt/archives/libnss3-1d_3.12.4-1_i386.deb

Then restarted Iceweasel and voila ..

I've then also checked the Debian bug reports to see if this has already been reported or was waiting for me to do that. This bug report showed up:

http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=561918

Hope this saves you some time ..

Бая отдавна се каня да си инсталирам Wiki.

Играя си сега с [[ikiwiki]] и се питам: Временните работи най-постоянни ли са ?