The latest Ubuntu release is out, and as its the Long Term Support version both my home media machine and work laptop received the full treatment, both are complete rebuilds (new harddrives) so an ideal upgrade path. For me its a worth while upgrade removing many of the irritations that i had with 8.04 on my work laptop, such as the integrated support for 3G mobilebroadband sticks, which just work with the simplest of wizards, faster bootup times and possibly the greatest relief, the fact that vmware workstation 7 worked flawlessly straight off.

I’m still using the 32bit version, but swapped out the kernel for the server one for the 3gb+ memory support with the simple commands

$ sudo apt-get update
$ sudo sudo apt-get install linux-headers-server linux-image-server linux-server

A lot of my settings came over just fine when I copied the contents of my ‘Home’ directory from the old hard drive to the new, and I’m well on my way removing all the eye candy that they have added, I’m not going to review anymore as there are no doubt a thousand reviews of it out there already. but well done Canonical, real progress and feels like more and more like a real contender

If your running JBoss or another Java server locally and you occasionally get the error

java.net.SocketException: IP_ADD_MEMBERSHIP failed (out of hardware filters?)

and suddenly nothing works, ie you cant reach your local server anymore via http, you may have found that it nearly always goes away after a reboot, but sometimes not, if you have a repeat offender for this and your are on a corporate VPN, then that may be your problem, if your VPN is set to “route all traffic through gateway”*, ‘all traffic’ often means even local (127.0.0.1), if you cant disable the setting, then the only work around i have found until now is to start your server with the VPN client disconnected, then connect once you are running (or if you have data-sources or mbeans, wait till they attempt to reach the database, then connect)

sad little tip for Easter Sunday, but it cant be helped

* This setting is found on checkpoint VPN-1 for windows, by going to the status tray when its not connected, and ‘right click’ –> ‘Settings’ , then on the ‘Connections’ tab, select your profile, and click the ‘properties’ button, then go to the ‘Advanced’ tab, it is the checkbox at the bottom.

This is a very old bug but affects at least Java 1.4 though 1.6 so pretty much hits all versions of domino, the problem is:

“Once an application has performed network access (i.e. urlconnection, parsing of xml document with external references, etc), the DNS settings get cached so any subsequent operation will use the old settings even if the real settings have changed. To reset everything, you have to restart the server since the default setting JVM setting is to cache forever.”

I.E., if any of your Java on domino makes a call to a website or network resource, and that resource changes its IP address, you have restart your JVM and therefore your whole Domino box, most people will restart a server to try and fix an unknown problem anyway so the problem will seem to have fixed its self, but some times its good to know why (i just hit it on my use of reCAPTCHA as provided by Chris Brandlehner)

sources:

http://stackoverflow.com/questions/1835421/java-dns-cache-viewer
http://www.rgagnon.com/javadetails/java-0445.html
http://www.mattryall.net/blog/2005/03/javas-awful-dns-caching