【正文】 ............................................. 17 管理界面與命令 .................................................................................................... 19 hdfs 運(yùn)行狀態(tài)界面 ........................................................................................... 19 Mapreduce 的運(yùn)行狀態(tài)界面 ........................................................................... 20 直接的命令行查看 .......................................................................................... 20 運(yùn)行的進(jìn)程查看 .............................................................................................. 21 5 架構(gòu)分析 ..................................................................................................................... 23 HDFS .................................................................................................................... 23 HDFS 的三個(gè)重要角色 .................................................................................... 24 HDFS 設(shè)計(jì)特點(diǎn) ............................................................................................... 25 MapReduce .......................................................................................................... 26 北京寬連十方數(shù)字技術(shù)有限公司 公開(kāi) 絕密 算法介紹 ......................................................................................................... 26 Hadoop 框架下的 mapreduce .......................................................................... 28 綜合架構(gòu)分析 ........................................................................................................ 29 6 Hadoop 的應(yīng)用 ............................................................................................................ 38 7 系統(tǒng)維護(hù) ..................................................................................................................... 39 Hadoop 的系統(tǒng)監(jiān)控 ............................................................................................... 39 Hadoop 中的命令（ Command）總結(jié) ...................................... 錯(cuò)誤！未定義書簽。 NameNode 與 JobTracker 單點(diǎn)故障說(shuō)明 ............................................................... 40 經(jīng)驗(yàn)總結(jié) ............................................................................................................... 40 如何在一個(gè) hadoop 集群新增或刪除一些機(jī)器而不重啟 ........................................ 41 新增節(jié)點(diǎn) ......................................................................................................... 41 刪除節(jié)點(diǎn) ......................................................................................................... 41 其它日常問(wèn)題說(shuō)明 ................................................................................................ 43 datanode 啟動(dòng)失敗，各 slave 節(jié)點(diǎn)的 namespaceIDs 與 masters不同 ............... 43 taskTracker 和 jobTracker 啟動(dòng)失敗 ............................................................... 44 Shuffle Error: Exceeded MAX_FAILED_UNIQUE_FETCHES。 bailingout ... 45 Too many fetchfailures .................................................................................. 45 能夠啟動(dòng) datanode，但 無(wú)法訪問(wèn)，也無(wú)法結(jié)束的錯(cuò)誤 ................................... 45 : Could not obtain block: ................................................. 46 : Java heap space ........................................... 46 解決 hadoop OutOfMemoryError 問(wèn)題： ......................................................... 46 Hadoop : ......................................................................... 46 防火墻的端口開(kāi)放要求 ......................................................................................... 47 與 HDFS 有關(guān)的地址及端口屬性 .............................................................