Rowanto Luo


Just another blog. or log.


  1. Docker and (Console) Logs Problem

    Anyone who used docker before and care about quality will have to deal with the logs problem. As we all know, docker runs in a container, and if we don't handle the logs in a special way, the logs will be lost when the container is restarted. In order to…

    on docker, logs, problem, solr, console log

  2. Broken Docker in Debian Jessie

    So after a few dist-upgrades, docker is not running anymore in my debian Jessie. A quick run of sudo service docker status shows me: ‚óŹ docker.service - Docker Application Container Engine Loaded: loaded (/lib/systemd/system/docker.service; disabled; vendor preset: enabled) Active: failed (Result: exit-code) since Wed 2015-09-02 00:…

    on debian, docker, aufs

  3. KDE is fully broken in Debian Jessie/Testing

    I use Debian Jessie, and I am the type who do this command frequently: sudo apt-get update && sudo apt-get dist-upgrade Now I am suffering from the consequences. The desktop is completely broken. I googled around, and there was nothing. So I thought something in my laptop is broken…

    on debian, jessie, kde, broken

  4. Why Datanode is Denied Communication With Namenode

    So for those trying to setup HDFS out there, and are struggling with this kind of error where it said datanode denied communication with namenode: 2015-05-07 08:04:19,694 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: Block pool BP-1184863888-172.17.0.3-1430984962919 (Datanode Uuid null) service to dockernamenode.…

    on hadoop, hdfs, datanode, namenode, error

  5. The Difference between For-Each Loop and forEach()

    People who have played enough with the brand new Java 8 will be familiar with the new forEach(fn(x)) loop in lambda. This syntax is quite popular among developers because it's easier and prettier to use than the normal For-Each loop. It is also popular in other languages, especially…

    on java, java8, foreach