重點在 namespaceId 的值，它是 hash( host+port )。
如果其他的 namenode 不合會怎樣？
不能啟動嗎？
總不可能每次 connect 都檢查這個值吧？

just do it!!!

TODO:
namenode namesystem.blockReceived

整理 code ？
1. prologue 及 epilogue。
2. indirect branch -> direct brance
3. code cache memory manager
4.

build hadoop

2010/06/03 build hadoop, problem:
ivy-download:
/home/tk/Software/hadoop/hadoop-svn-0.20.2/build.xml:1630: java.net.SocketException: Network is unreachable
mentioned in this post that :

Setting bindv6only to 0 in /etc/sysctl.d/bindv6only.conf on my debian squeeze installation seems to have fixed the problem. Sorry for littering the list.

This actually is a special issue in Debina squeeze/sid version as explained in another post.
So what to do is:
1. Setting bindv6only to 0 in /etc/sysctl.d/bindv6only.conf
2. restart procps: sudo invoke-rc.d procps restart

now we have problem for java version

debug

目前想改 repz 的instruction，讓它們跟 qemu 的行為一樣，這樣比較好debug，這很重要，雖然implement 上會比較慢，但開發速度可以快很多，確定都ok了之後就可以改回來。