簡介：
在不需要重灌作業系統的情況下完全解除安裝HDP，並準備好自動安裝HDP2.6的環境。

文章：
升級HDP失敗後，我被迫徹底清除HDP 2.4，Ambari 2.5並安裝HDP 2.6。 我想避免重新安裝作業系統，所以執行了如下的步驟。

1、停止在Ambari中的所有服務或殺死他們
可以通過ambari控制檯停止所有服務。在我的情況下，Ambari在降級時損壞了他的資料庫，無法啟動。 所以我手動殺死所有節點上的所有程序：

ps−uhdfs(可以看到所有服務列表) kill PID

2、在所有叢集節點上執行python指令碼

$ python /usr/lib/python2.6/site-packages/ambari_agent/HostCleanup.py –silent –skip=users
3、刪除所有節點上的Hadoop包
yum remove hive*
yum remove oozie*
yum remove pig*
yum remove zookeeper*
yum remove tez*
yum remove hbase*
yum remove ranger*
yum remove knox*
yum remove storm*
yum remove accumulo*
yum remove falcon*
yum remove ambari-metrics-hadoop-sink
yum remove smartsense-hst
yum remove slider_2_4_2_0_258
yum remove ambari-metrics-monitor
yum remove spark2_2_5_3_0_37-yarn-shuffle
yum remove spark_2_5_3_0_37-yarn-shuffle
yum remove ambari-infra-solr-client
4、刪除ambari-server（在Ambari主機上）和ambari-agent（在所有節點上）
ambari-server stop
ambari-agent stop
yum erase ambari-server
yum erase ambari-agent
5、刪除所有節點上的儲存庫
rm -rf /etc/yum.repos.d/ambari.repo /etc/yum.repos.d/HDP*
yum clean all
6、刪除所有節點上的日誌資料夾
rm -rf /var/log/ambari-agent
rm -rf /var/log/ambari-metrics-grafana
rm -rf /var/log/ambari-metrics-monitor
rm -rf /var/log/ambari-server/
rm -rf /var/log/falcon
rm -rf /var/log/flume
rm -rf /var/log/hadoop
rm -rf /var/log/hadoop-mapreduce
rm -rf /var/log/hadoop-yarn
rm -rf /var/log/hive
rm -rf /var/log/hive-hcatalog
rm -rf /var/log/hive2
rm -rf /var/log/hst
rm -rf /var/log/knox
rm -rf /var/log/oozie
rm -rf /var/log/solr
rm -rf /var/log/zookeeper
7、刪除所有節點上的Hadoop資料夾，包括HDFS資料
rm -rf /hadoop/*
rm -rf /hdfs/hadoop
rm -rf /hdfs/lost+found
rm -rf /hdfs/var
rm -rf /local/opt/hadoop
rm -rf /tmp/hadoop
rm -rf /usr/bin/hadoop
rm -rf /usr/hdp
rm -rf /var/hadoop
8、刪除所有節點上的配置資料夾
rm -rf /etc/ambari-agent
rm -rf /etc/ambari-metrics-grafana
rm -rf /etc/ambari-server
rm -rf /etc/ams-hbase
rm -rf /etc/falcon
rm -rf /etc/flume
rm -rf /etc/hadoop
rm -rf /etc/hadoop-httpfs
rm -rf /etc/hbase
rm -rf /etc/hive
rm -rf /etc/hive-hcatalog
rm -rf /etc/hive-webhcat
rm -rf /etc/hive2
rm -rf /etc/hst
rm -rf /etc/knox
rm -rf /etc/livy
rm -rf /etc/mahout
rm -rf /etc/oozie
rm -rf /etc/phoenix
rm -rf /etc/pig
rm -rf /etc/ranger-admin
rm -rf /etc/ranger-usersync
rm -rf /etc/spark2
rm -rf /etc/tez
rm -rf /etc/tez_hive2
rm -rf /etc/zookeeper

9、刪除所有節點上的PID

rm -rf /var/run/ambari-agent
rm -rf /var/run/ambari-metrics-grafana
rm -rf /var/run/ambari-server
rm -rf /var/run/falcon
rm -rf /var/run/flume
rm -rf /var/run/hadoop
rm -rf /var/run/hadoop-mapreduce
rm -rf /var/run/hadoop-yarn
rm -rf /var/run/hbase
rm -rf /var/run/hive
rm -rf /var/run/hive-hcatalog
rm -rf /var/run/hive2
rm -rf /var/run/hst
rm -rf /var/run/knox
rm -rf /var/run/oozie
rm -rf /var/run/webhcat
rm -rf /var/run/zookeeper
10、刪除所有節點上的庫資料夾
rm -rf /usr/lib/ambari-agent
rm -rf /usr/lib/ambari-infra-solr-client
rm -rf /usr/lib/ambari-metrics-hadoop-sink
rm -rf /usr/lib/ambari-metrics-kafka-sink
rm -rf /usr/lib/ambari-server-backups
rm -rf /usr/lib/ams-hbase
rm -rf /usr/lib/mysql
rm -rf /var/lib/ambari-agent
rm -rf /var/lib/ambari-metrics-grafana
rm -rf /var/lib/ambari-server
rm -rf /var/lib/flume
rm -rf /var/lib/hadoop-hdfs
rm -rf /var/lib/hadoop-mapreduce
rm -rf /var/lib/hadoop-yarn
rm -rf /var/lib/hive2
rm -rf /var/lib/knox
rm -rf /var/lib/smartsense
rm -rf /var/lib/storm

11、清除所有節點上的資料夾/var/tmp/*

rm -rf /var/tmp/*
12、從cron在所有節點上刪除HST
/usr/hdp/share/hst/bin/hst-scheduled-capture.sh sync
/usr/hdp/share/hst/bin/hst-scheduled-capture.sh

13、刪除資料庫。 刪除MySQL和Postgres的例項，以便Ambari安裝和配置新的資料庫。

yum remove mysql mysql-server
yum erase postgresql
rm -rf /var/lib/pgsql
rm -rf /var/lib/mysql
14、刪除所有節點上的符號連結。
尤其是檢查資料夾/usr/sbin和/usr/lib/python2.6/site-packages

cd /usr/bin
rm -rf accumulo
rm -rf atlas-start
rm -rf atlas-stop
rm -rf beeline
rm -rf falcon
rm -rf flume-ng
rm -rf hbase
rm -rf hcat
rm -rf hdfs
rm -rf hive
rm -rf hiveserver2
rm -rf kafka
rm -rf mahout
rm -rf mapred
rm -rf oozie
rm -rf oozied.sh
rm -rf phoenix-psql
rm -rf phoenix-queryserver
rm -rf phoenix-sqlline
rm -rf phoenix-sqlline-thin
rm -rf pig
rm -rf python-wrap
rm -rf ranger-admin
rm -rf ranger-admin-start
rm -rf ranger-admin-stop
rm -rf ranger-kms
rm -rf ranger-usersync
rm -rf ranger-usersync-start
rm -rf ranger-usersync-stop
rm -rf slider
rm -rf sqoop
rm -rf sqoop-codegen
rm -rf sqoop-create-hive-table
rm -rf sqoop-eval
rm -rf sqoop-export
rm -rf sqoop-help
rm -rf sqoop-import
rm -rf sqoop-import-all-tables
rm -rf sqoop-job
rm -rf sqoop-list-databases
rm -rf sqoop-list-tables
rm -rf sqoop-merge
rm -rf sqoop-metastore
rm -rf sqoop-version
rm -rf storm
rm -rf storm-slider
rm -rf worker-lanucher
rm -rf yarn
rm -rf zookeeper-client
rm -rf zookeeper-server
rm -rf zookeeper-server-cleanup

15、刪除所有節點上的服務使用者

userdel -r accumulo
userdel -r ambari-qa
userdel -r ams
userdel -r falcon
userdel -r flume
userdel -r hbase
userdel -r hcat
userdel -r hdfs
userdel -r hive
userdel -r kafka
userdel -r knox
userdel -r mapred
userdel -r oozie
userdel -r ranger
userdel -r spark
userdel -r sqoop
userdel -r storm
userdel -r tez
userdel -r yarn
userdel -r zeppelin
userdel -r zookeeper
16、在所有節點上執行find / -name **
你一定會找到更多的檔案/資料夾。 刪除它們

find / -name ambari
find / -name accumulo
find / -name atlas
find / -name beeline
find / -name falcon
find / -name flume
find / -name hadoop
find / -name hbase
find / -name hcat
find / -name hdfs
find / -name hdp
find / -name hive
find / -name hiveserver2
find / -name kafka
find / -name mahout
find / -name mapred
find / -name oozie
find / -name phoenix
find / -name pig
find / -name ranger
find / -name slider
find / -name sqoop
find / -name storm
find / -name yarn
find / -name zookeeper
17、重新啟動所有節點
reboot