1.检查Standby Namenode 的状态。
[hadoop@big82 current]$
hdfs dfs -ls /
—我的Hdfs上有一个目录：/test1
Found 1 items
drwxr-xr-x – hadoop supergroup 0 2022-04-16 18:47 /test1
[hadoop@big82 current]$
hdfs haadmin -getAllServiceState
big81:9000 active
big82:9000 standby –状态正常。
2.模拟Standby namenode 损坏。
[hadoop@big82 current]$ pwd
/data02/current
[hadoop@big82 current]$ ll
total 16
-rw-rw-r– 1 hadoop hadoop 388 Apr 17 09:50 fsimage_0000000000000000000
-rw-rw-r– 1 hadoop hadoop 62 Apr 17 09:50 fsimage_0000000000000000000.md5
-rw-rw-r– 1 hadoop hadoop 2 Apr 17 09:50 seen_txid
-rw-rw-r– 1 hadoop hadoop 216 Apr 17 09:50 VERSION
[hadoop@big82 current]$
rm -rf * 将Standby Namenode里面的数据全部删除。
此时系统尚未感知到standby namenode 挂了，我们重启standby namenode ,让集群知道Standby namenode 不在了。
3.重启Standby namenode ;
[hadoop@big82 current]$ hdfs –daemon stop namenode
[hadoop@big82 current]$ hdfs –daemon start namenode
[hadoop@big82 current]$ jps
18594 ResourceManager
22088 Jps
17803 DFSZKFailoverController
[hadoop@big82 current]$ hdfs haadmin -getAllServiceState
big81:9000 active
2022-04-17 10:12:43,122 INFO ipc.Client: Retrying connect to server: big82/192.168.1.82:9000. Already tried 0 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=1, sleepTime=1000 MILLISECONDS)
big82:9000 Failed to connect: Call From big82/192.168.1.82 to big82:9000 failed on connection exception: java.net.ConnectException: Connection refused; For more details see: http://wiki.apache.org/hadoop/ConnectionRefused
可以看到Standby Namenode 无法启动。同时Datanode节点的日志中出现：ipc连接异常的报错
2022-04-17 10:12:38,881 INFO org.apache.hadoop.ipc.Client: Retrying connect to server: big82/192.168.1.82:9000. Already tried 3 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1000 MILLISECONDS)
2022-04-17 10:15:30,301 WARN org.apache.hadoop.hdfs.server.datanode.DataNode: IOException in offerService
java.net.ConnectException: Call From big91/192.168.1.91 to big82:9000 failed on connection exception: java.net.ConnectException: Connection refused; For more details see: http://wiki.apache.org/hadoop/ConnectionRefused
at sun.reflect.GeneratedConstructorAccessor11.newInstance(Unknown Source)
4.修复Standby namenode
[hadoop@big82 current]$
hdfs namenode -bootstrapStandby —格式化Standby Namenode;
Java HotSpot(TM) 64-Bit Server VM warning: Cannot open file /data02/logs/hadoop/gc.log due to No such file or directory
log4j:ERROR Could not find value for key log4j.appender.DRFAAUDIT
log4j:ERROR Could not instantiate appender named “DRFAAUDIT”.
2022-04-17 10:17:00,047 INFO namenode.NameNode: STARTUP_MSG:
/************************************************************
STARTUP_MSG: Starting NameNode
STARTUP_MSG: host = big82/192.168.1.82
STARTUP_MSG: args = [-bootstrapStandby]
STARTUP_MSG: version = 3.1.1
………………………………………………………………………………
STARTUP_MSG: build = https://github.com/apache/hadoop -r 2b9a8c1d3a2caf1e733d57f346af3ff0d5ba529c; compiled by ‘leftnoteasy’ on 2018-08-02T04:26Z
STARTUP_MSG: java = 1.8.0_261
************************************************************/
2022-04-17 10:17:00,059 INFO namenode.NameNode: registered UNIX signal handlers for [TERM, HUP, INT]
2022-04-17 10:17:00,066 INFO namenode.NameNode: createNameNode [-bootstrapStandby]
2022-04-17 10:17:00,279 INFO ha.BootstrapStandby: Found nn: fgedunn1, ipc: big81/192.168.1.81:9000
=====================================================
About to bootstrap Standby ID fgedunn2 from:
Nameservice ID: fgeduns
Other Namenode ID: fgedunn1
Other NN’s HTTP address: http://big81:50070
Other NN’s IPC address: big81/192.168.1.81:9000
Namespace ID: 166178331
Block pool ID: BP-1145621526-192.168.1.81-1650104239176
Cluster ID: CID-6e446eb6-01fa-4f97-9e08-9f5842bf335a
Layout version: -64
isUpgradeFinalized: true
=====================================================
Re-format filesystem in Storage Directory root= /data02; location= null ? (Y or N)
y –确认重新格式化
2022-04-17 10:17:34,117 INFO common.Storage: Will remove files: []
2022-04-17 10:17:34,129 INFO common.Storage:
Storage directory /data02 has been successfully formatted. –格式化成功。
2022-04-17 10:17:34,760 INFO
namenode.FSEditLog: Edit logging is async:true –同步完成。
2022-04-17 10:17:35,015 INFO namenode.TransferFsImage: Opening connection to http://big81:50070/imagetransfer?getimage=1&txid=0&storageInfo=-64:166178331:1650104239176:CID-6e446eb6-01fa-4f97-9e08-9f5842bf335a&bootstrapstandby=true
2022-04-17 10:17:35,060 INFO common.Util: Combined time for file download and fsync to all disks took 0.00s. The file download took 0.00s at 0.00 KB/s. Synchronous (fsync) write to disk of /data02/current/fsimage.ckpt_0000000000000000000 took 0.00s.
2022-04-17 10:17:35,060 INFO namenode.TransferFsImage: Downloaded file fsimage.ckpt_0000000000000000000 size 388 bytes.
2022-04-17 10:17:35,077 INFO namenode.NameNode: SHUTDOWN_MSG:
/************************************************************
SHUTDOWN_MSG: Shutting down NameNode at big82/192.168.1.82
************************************************************/
5.启动Standby namenode;
[hadoop@big82 data02]$ cd current
[hadoop@big82 current]$ ll —可以看到格式之后，重新生成了fsimage
total 16
-rw-rw-r– 1 hadoop hadoop 388 Apr 17 10:17 fsimage_0000000000000000000
-rw-rw-r– 1 hadoop hadoop 62 Apr 17 10:17 fsimage_0000000000000000000.md5
-rw-rw-r– 1 hadoop hadoop 2 Apr 17 10:17 seen_txid
-rw-rw-r– 1 hadoop hadoop 216 Apr 17 10:17 VERSION
[hadoop@big82 current]$
hdfs –daemon start namenode
[hadoop@big82 current]$ jps
18594 ResourceManager
17803 DFSZKFailoverController
22475 Jps
22396 NameNode –Standby namenode 又启动了。
[hadoop@big82 current]$ hdfs haadmin -getAllServiceState
big81:9000 active
big82:9000 standby –备Standby namenode;
6.检查Datanode 是否还有报错。
2022-04-17 10:19:20,659 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: Block pool Block pool BP-1145621526-192.168.1.81-1650104239176 (Datanode Uuid 31d0fd01-959e-434b-998e-016345cf3d7e) service to big82/192.168.1.82:9000 successfully registered with NN
2022-04-17 10:19:20,687 INFO org.apache.hadoop.hdfs.server.datanode.
DataNode: Successfully sent block report 0x95b5123c058e9e1f, containing 3 storage report(s), of which we sent 3.
The reports had 0 total blocks and used 1 RPC(s). This took 1 msec to generate and 19 msecs for RPC and
NN processing
. Got back no commands
说明Standby namenode可以正常处理了。
7.检查我们hadoop 目录。
[hadoop@big82 current]$ hdfs dfs -ls /
Found 1 items
drwxr-xr-x – hadoop supergroup 0 2022-04-16 18:47 /test1
至此，修复完成。