篇首语：本文由小编为大家整理，主要介绍了hive的hiveserver2模式启动不起来，发现Hadoop一直处于安全模式相关的知识，希望对你有一定的参考价值。

hive的hiveserver2模式启动不起来，发现Hadoop一直处于安全模式

命令介绍

命令hadoop fs –safemode get 查看安全模式状态
命令hadoop fs –safemode enter 进入安全模式状态
命令hadoop fs –safemode leave 离开安全模式状态

用Hadoop fsck查看破坏丢失的文件位置

hadoop  fsckUsage: DFSck  [-move | -delete | -openforwrite] [-files [-blocks [-locations | -racks]]]                     检查这个目录中的文件是否完整        -move               破损的文件移至/lost+found目录        -delete             删除破损的文件        -openforwrite   打印正在打开写操作的文件        -files                 打印正在check的文件名        -blocks             打印block报告 （需要和-files参数一起使用）        -locations         打印每个block的位置信息（需要和-files参数一起使用）        -racks               打印位置信息的网络拓扑图 （需要和-files参数一起使用）

第一步：检查hadoop文件系统hadoop fsck /

[root@node03 export]# hadoop fsck /.................................................................................................................Status: CORRUPT                    #Hadoop状态：不正常 Total size:    273821489 B Total dirs:    403 Total files:   213 Total symlinks:        0 Total blocks (validated):  201 (avg. block size 1362295 B)  ********************************  UNDER MIN REPL"D BLOCKS:  2 (0.99502486 %)  dfs.namenode.replication.min: 1  CORRUPT FILES:    2                           #损坏了两个文件  MISSING BLOCKS:   2                           #丢失了两个块  MISSING SIZE:     6174 B  CORRUPT BLOCKS:   2  ******************************** Minimally replicated blocks:   199 (99.004974 %) Over-replicated blocks:    0 (0.0 %) Under-replicated blocks:   0 (0.0 %) Mis-replicated blocks:     0 (0.0 %) Default replication factor:    3 Average block replication: 2.8208954 Corrupt blocks:        2 Missing replicas:      0 (0.0 %) Number of data-nodes:      3 Number of racks:       1FSCK ended at Fri Aug 23 10:43:11 CST 2019 in 12 milliseconds

看到这些代表hadoop集群不正常，有文件丢失：

? .............Status: CORRUPT #Hadoop状态：不正常

CORRUPT FILES: 2 #损坏了两个文件
MISSING BLOCKS: 2 #丢失了两个块

第二步：将hadoop文件状态信息打印到文件中

内容太多，截取了一部分信息

hadoop fsck / -files -blocks -locations -racks >/export/missingFile.txt 将检查到的内容打印到/export/missingFile.txt文件中

[root@node03 export]# hadoop fsck /  -files -blocks -locations  -racks >/export/missingFile.txt/flink-checkpoint/11748bc079799f330078967fbf018a48/chk-74/_metadata 452 bytes, 1 block(s):  OK0. BP-2135962035-192.168.52.100-1562110398602:blk_1073742825_2005 len=452 Live_repl=1 [/default-rack/192.168.52.110:50010]/flink-checkpoint/11748bc079799f330078967fbf018a48/shared /flink-checkpoint/11748bc079799f330078967fbf018a48/taskowned /flink-checkpoint/42d81db182771fe71932120fa8933612 /flink-checkpoint/42d81db182771fe71932120fa8933612/chk-950 /flink-checkpoint/42d81db182771fe71932120fa8933612/chk-950/_metadata 337 bytes, 1 block(s):  OK0. BP-2135962035-192.168.52.100-1562110398602:blk_1073745657_4837 len=337 Live_repl=1 [/default-rack/192.168.52.120:50010]/flink-checkpoint/42d81db182771fe71932120fa8933612/chk-950/f59c63a0-a35d-4d4b-8e73-72c2aa1dd383 5657 bytes, 1 block(s):  OK0. BP-2135962035-192.168.52.100-1562110398602:blk_1073745656_4836 len=5657 Live_repl=1 [/default-rack/192.168.52.100:50010]/flink-checkpoint/42d81db182771fe71932120fa8933612/shared /flink-checkpoint/42d81db182771fe71932120fa8933612/taskowned /flink-checkpoint/50aebc9e7aac85fd33bff905972a6e01 /flink-checkpoint/50aebc9e7aac85fd33bff905972a6e01/chk-9 /flink-checkpoint/50aebc9e7aac85fd33bff905972a6e01/chk-9/_metadata 451 bytes, 1 block(s):  OK0. BP-2135962035-192.168.52.100-1562110398602:blk_1073742843_2023 len=451 Live_repl=1 [/default-rack/192.168.52.100:50010]/flink-checkpoint/50aebc9e7aac85fd33bff905972a6e01/chk-9/c58c8c49-8782-41b4-a3df-2fa7ff1d1eba 5663 bytes, 1 block(s):  OK0. BP-2135962035-192.168.52.100-1562110398602:blk_1073742842_2022 len=5663 Live_repl=1 [/default-rack/192.168.52.120:50010]/flink-checkpoint/50aebc9e7aac85fd33bff905972a6e01/shared /flink-checkpoint/50aebc9e7aac85fd33bff905972a6e01/taskowned /flink-checkpoint/626ea65de810a2ec3b1799b605a6a995 /flink-checkpoint/626ea65de810a2ec3b1799b605a6a995/chk-175 /flink-checkpoint/626ea65de810a2ec3b1799b605a6a995/chk-175/19195239-a205-4462-921d-09e0483a4080 5663 bytes, 1 block(s): /flink-checkpoint/626ea65de810a2ec3b1799b605a6a995/chk-175/19195239-a205-4462-921d-09e0483a4080: CORRUPT blockpool BP-2135962035-192.168.52.100-1562110398602 block blk_1073743749 MISSING 1 blocks of total size 5663 B0. BP-2135962035-192.168.52.100-1562110398602:blk_1073743749_2929 len=5663 MISSING!/flink-checkpoint/626ea65de810a2ec3b1799b605a6a995/chk-175/_metadata 511 bytes, 1 block(s): /flink-checkpoint/626ea65de810a2ec3b1799b605a6a995/chk-175/_metadata: CORRUPT blockpool BP-2135962035-192.168.52.100-1562110398602 block blk_1073743750 MISSING 1 blocks of total size 511 B0. BP-2135962035-192.168.52.100-1562110398602:blk_1073743750_2930 len=511 MISSING!

可以看到正常文件后面都有ok字样，有MISSING!字样的就是丢失的文件。

/flink-checkpoint/626ea65de810a2ec3b1799b605a6a995/chk-175/19195239-a205-4462-921d-09e0483a4080: CORRUPT blockpool BP-2135962035-192.168.52.100-1562110398602 block blk_1073743749
MISSING 1 blocks of total size 5663 B

/flink-checkpoint/626ea65de810a2ec3b1799b605a6a995/chk-175/_metadata: CORRUPT blockpool BP-2135962035-192.168.52.100-1562110398602 block blk_1073743750
MISSING 1 blocks of total size 511 B

根据这个的路劲可以在hadoop浏览器界面中找到对应的文件路径，如下图：

第三步：修复两个丢失、损坏的文件

[root@node03 conf]# hdfs debug recoverLease -path /flink-checkpoint/626ea65de810a2ec3b1799b605a6a995/chk-175/19195239-a205-4462-921d-09e0483a4080 -retries 10

[root@node03 conf]# hdfs debug recoverLease -path /flink-checkpoint/626ea65de810a2ec3b1799b605a6a995/chk-175/_metadata -retries 10

[root@node03 conf]# hdfs debug recoverLease -path /flink-checkpoint/626ea65de810a2ec3b1799b605a6a995/chk-175/19195239-a205-4462-921d-09e0483a4080 -retries 10recoverLease SUCCEEDED on /flink-checkpoint/626ea65de810a2ec3b1799b605a6a995/chk-175/19195239-a205-4462-921d-09e0483a4080[root@node03 conf]# hdfs debug recoverLease -path /flink-checkpoint/626ea65de810a2ec3b1799b605a6a995/chk-175/_metadata -retries 10recoverLease SUCCEEDED on /flink-checkpoint/626ea65de810a2ec3b1799b605a6a995/chk-175/_metadata[root@node03 conf]# 

可以看到：

...........Status: HEALTHY Total size:    273815315 B Total dirs:    403 Total files:   211 Total symlinks:        0 Total blocks (validated):  199 (avg. block size 1375956 B) Minimally replicated blocks:   199 (100.0 %) Over-replicated blocks:    0 (0.0 %) Under-replicated blocks:   0 (0.0 %) Mis-replicated blocks:     0 (0.0 %) Default replication factor:    3 Average block replication: 2.8492463 Corrupt blocks:        0 Missing replicas:      0 (0.0 %) Number of data-nodes:      3 Number of racks:       1FSCK ended at Fri Aug 23 11:15:01 CST 2019 in 11 milliseconds

...........Status: HEALTHY 集群状态：健康

现在重新启动hadoop就不会一直处于安全模式了，hiveserver2也能正常启动了。。

第四：意外状况

如果修复不了，或者提示修复成功但是集群状态还是下面这样：

.............Status: CORRUPT                    #Hadoop状态：不正常 Total size:    273821489 B Total dirs:    403 Total files:   213 Total symlinks:        0 Total blocks (validated):  201 (avg. block size 1362295 B)  ********************************  UNDER MIN REPL"D BLOCKS:  2 (0.99502486 %)  dfs.namenode.replication.min: 1  CORRUPT FILES:    2                           #损坏了两个文件  MISSING BLOCKS:   2                           #丢失了两个块  MISSING SIZE:     6174 B  CORRUPT BLOCKS:   2  ******************************** Minimally replicated blocks:   199 (99.004974 %) Over-replicated blocks:    0 (0.0 %) Under-replicated blocks:   0 (0.0 %) Mis-replicated blocks:     0 (0.0 %) Default replication factor:    3 Average block replication: 2.8208954 Corrupt blocks:        2 Missing replicas:      0 (0.0 %) Number of data-nodes:      3 Number of racks:       1FSCK ended at Fri Aug 23 10:43:11 CST 2019 in 12 milliseconds

1、如果损坏的文件不重要

首先：将找到的损坏文件备份好

然后：执行[root@node03 export]# hadoop fsck / -delete将损坏文件删除

[root@node03 export]# hadoop fsck / -delete

此命令一次不成功可以多试几次，前提是丢失、损坏的文件不重要！！！！！！！！！！

2、如果损坏的文件很重要不能丢失

可以先执行此命令：hadoop fs –safemode leave 强制离开安全模式状态

[root@node03 export]# hadoop fs –safemode leave

此操作不能完全解决问题，只能暂时让集群能够工作！！！！

而且，以后每次启动hadoop集群都要执行此命令，直到问题彻底解决。

以上是关于hive的hiveserver2模式启动不起来，发现Hadoop一直处于安全模式的主要内容，如果未能解决你的问题，请参考以下文章