1. DataX 简介：
DataX 是阿里巴巴集团内被广泛使用的离线数据同步工具/平台，实现包括 MySQL、Oracle、SQLServer、Postgre、HDFS、Hive、ADS、HBase、TableStore(OTS)、MaxCompute(ODPS)、DRDS 等各种异构数据源之间高效的数据同步功能。本例中将使用 DataX 实现 Hive 与MySQL之间的数据传输。
本例中所使用的资源为三台 2 核 4G 内存，40G SSD 硬盘的 DC2，EIP 带宽为 1M。
DataC：10.254.125.48
Hive：10.254.237.61
MySQL：10.254.116.249
此处 IP 为云主机内网 IP，方便三台主机之间内网通信，而下载文件或外部访问则需 EIP，即外网 IP 或弹性 IP。有关滴滴云 EIP 的使用请参考以下链接：https://help.didiyun.com/hc/kb/section/1035272/
2. 在 Hive 节点安装 Hadoop 2.7.7+Hive 2.3.4
-
滴滴云主机出于安全考虑，默认不能通过 root 用户直接登录，需要先用 dc2-user 登录，让后用 sudo su 切换至 root。本例中默认全部以 dc2-user 用户运行命令，Hadoop 默认用户同样为 dc2-user。
-
设置免密登录，为 dc2-user 生成公钥。
ssh-keygen -b 4096
Generating public/private rsa key pair.
Enter file in which to save the key (/home/hadoop/.ssh/id_rsa):
Created directory '/home/hadoop/.ssh'.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/hadoop/.ssh/id_rsa.
Your public key has been saved in /home/hadoop/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:zRhhVpEfSIZydqV75775sZB0GBjZ/f7nnZ4mgfYrWa8 hadoop@10-254-149-24
The key's randomart image is:
+---[RSA 4096]----+
| ++=*+ . |
| .o+o+o+. . |
| +...o o .|
| = .. o .|
| S + oo.o |
| +.=o .|
| . +o+..|
| o +.+O|
| .EXO=|
+----[SHA256]-----+
输入以下命令将生成的公钥复制到本机：
ssh-copy-id -i $HOME/.ssh/id_rsa.pub dc2-user@localhost
- 配置 Java 环境
- 下载 JDK
cd /home/dc2-user
wget --no-check-certificate --no-cookies --header "Cookie: oraclelicense=accept-securebackup-cookie" http://download.oracle.com/otn-pub/java/jdk/8u191-b12/2787e4a523244c269598db4e85c51e0c/jdk-8u191-linux-x64.tar.gz
tar -zxf jdk-8u191-linux-x64.tar.gz
- 配置 Java 变量
sudo vi /etc/profile.d/jdk-1.8.sh
export JAVA_HOME=/home/dc2-user/jdk1.8.0_191
export JRE_HOME=${JAVA_HOME}/jre
export CLASSPATH=.:${JAVA_HOME}/lib:${JRE_HOME}/lib
export PATH=${JAVA_HOME}/bin:$PATH
- 使环境变量生效
source /etc/profile
- 查看 Java 版本
java -version
java version "1.8.0_191"
Java(TM) SE Runtime Environment (build 1.8.0_191-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.191-b12, mixed mode)
出现以上输出，说明 Java 环境已经配置成功。
- 安装 Hadoop
节点下载 Hadoop 2.7.7 并解压
cd /home/dc2-user
wget http://mirrors.shu.edu.cn/apache/hadoop/common/hadoop-2.7.7/hadoop-2.7.7.tar.gz<br/>
tar zxf hadoop-2.7.7.tar.gz<br/>
在 /home/dc2-user/hadoop-2.7.7/etc/hadoop 下需要配置的5个文件分别是 hadoop-env.sh、core-site.xml、hdfs-site.xml、yarn-site.xml、mapred-site.xml
- hadoop-env.sh添加如下内容
export JAVA_HOME=/home/dc2-user/jdk1.8.0_191
export HDFS_NAMENODE_USER="dc2-user"
export HDFS_DATANODE_USER="dc2-user"
export HDFS_SECONDARYNAMENODE_USER="dc2-user"
export YARN_RESOURCEMANAGER_USER="dc2-user"
export YARN_NODEMANAGER_USER="dc2-user"
- core-site.xml
<configuration>
<property>
<name>fs.default.name</name>
<value>hdfs://10.254.237.61:9000</value>
</property>
</configuration>
- hdfs-site.xml
<configuration>
<property>
<name>dfs.namenode.name.dir</name>
<value>/home/dc2-user/data/nameNode</value>
</property>
<property>
<name>dfs.datanode.data.dir</name>
<value>/home/dc2-user/data/dataNode</value>
</property>
<property>
<name>dfs.replication</name>
<value>1</value>
</property>
<property>
<name>dfs.http.address</name>
<value>10.254.237.61:50070</value>
</property>
</configuration>
- yarn-site.xml
<configuration>
<property>
<name>yarn.nodemanager.auxservices.mapreduce_shuffle.class</name>
<value>org.apache.hadoop.mapred.ShuffleHandler</value>
</property>
<property>
<name>yarn.nodemanager.aux-services</name>
<value>mapreduce_shuffle</value>
</property>
</configuration>
- mapred-site.xml
<configuration>
<property>
<name>mapreduce.framework.name</name>
<value>yarn</value>
</property>
</configuration>
- 配置 Hadoop 环境变量
sudo vi /etc/profile.d/hadoop-2.7.7.sh
export HADOOP_HOME="/home/dc2-user/hadoop-2.7.7"
export PATH="$HADOOP_HOME/bin:$PATH"
export HADOOP_CONF_DIR=$HADOOP_HOME/etc/hadoop
export YARN_CONF_DIR=$HADOOP_HOME/etc/hadoop
使环境变量生效
source /etc/profile
输入 haoop version 看是否有输出，验证环境变量是否生效
hadoop version
Hadoop 2.7.7
Subversion Unknown -r c1aad84bd27cd79c3d1a7dd58202a8c3ee1ed3ac
Compiled by stevel on 2018-07-18T22:47Z
Compiled with protoc 2.5.0
From source with checksum 792e15d20b12c74bd6f19a1fb886490
This command was run using /home/dc2-user/hadoop-2.7.7/share/hadoop/common/hadoop-common-2.7.7.jar
- 格式化 HDFS
/home/dc2-user/hadoop-2.7.7/bin/hdfs namenode -format testCluster
- 开启服务
/home/dc2-user/hadoop-2.7.7/sbin/start-dfs.sh
/home/dc2-user/hadoop-2.7.7/sbin/start-yarn.sh
- 查看服务是否已启动
jps
13680 Jps
13268 ResourceManager
13367 NodeManager
12956 DataNode
13117 SecondaryNameNode
12830 NameNode
出现以上输出，说明服务已经正常启动，可以通过 Hive 的公网 IP 访问 DFS 的 web 页面，注意要打开安全组的 50070 端口，关于滴滴云安全组的使用请参考以下链接：https://help.didiyun.com/hc/kb/article/1091031/
注：公网开放 50070 端口可能会被黑客利用植入木马，因此建议在安全组中限制可访问的来源 IP，或者不在安全组中开放此端口。
3. Hive 2.3.4 安装和配置
Hive 是基于 Hadoop 的一个数据仓库，可以将结构化的数据文件映射为一张表，并提供类 SQL 查询功能，Hive 底层将SQL 语句转化为 MapReduce 任务运行。
- 下载 Hive 2.3.4 到 Master 的 /home/dc2-user 并解压
wget http://mirror.bit.edu.cn/apache/hive/hive-2.3.4/apache-hive-2.3.4-bin.tar.gz
tar zxvf apache-hive-2.3.4-bin.tar.gz
- 设置 Hive 环境变量
编辑 /etc/profile.d/hive.sh 文件, 在其中添加以下内容：
sudo vi /etc/profile.d/hive.sh
export HIVE_HOME=/home/dc2-user/apache-hive-2.3.4-bin
export PATH=$PATH:$HIVE_HOME/bin
使环境变量生效：
source /etc/profile
- 配置 Hive
重命名以下配置文件:
cd apache-hive-2.3.4-bin/conf/
cp hive-env.sh.template hive-env.sh
cp hive-default.xml.template hive-site.xml
cp hive-log4j2.properties.template hive-log4j2.properties
cp hive-exec-log4j2.properties.template hive-exec-log4j2.properties
修改 hive-env.sh:
export JAVA_HOME=/home/dc2-user/jdk1.8.0_191
export HADOOP_HOME=/home/dc2-user/hadoop-2.7.7
export HIVE_HOME=/home/dc2-user/apache-hive-2.3.4-bin
export HIVE_CONF_DIR=$HIVE_HOME/conf
修改 hive-site.xml
修改对应属性的 value 值
vi hive-site.xml
<configuration>
<property>
<name>hive.exec.scratchdir</name>
<value>/tmp/hive-${user.name}</value>
</property>
<property>
<name>hive.exec.local.scratchdir</name>
<value>/tmp/${user.name}</value>
</property>
<property>
<name>hive.downloaded.resources.dir</name>
<value>/tmp/hive/resources</value>
</property>
<property>
<name> hive.querylog.location</name>
<value>/tmp/${user.name}</value>
</property>
<property>
<name>hive.server2.logging.operation.log.location</name>
<value>/tmp/${user.name}/operation_logs</value>
</property>
</configuration>
- 配置 Hive Metastore
Hive Metastore 是用来获取 Hive 表和分区的元数据，本例中使用 MariaDB 来存储此类元数据。
下载 mysql-connector-java-5.1.40-bin.jar 放入 $HIVE_HOME/lib 下并在 hive-site.xml 中添加 MySQL 数据库连接信息。
<configuration>
<property>
<name>javax.jdo.option.ConnectionURL</name>
<value>jdbc:mysql://localhost:3306/hive?createDatabaseIfNotExist=true</value>
</property>
<property>
<name>javax.jdo.option.ConnectionDriverName</name>
<value>com.mysql.jdbc.Driver</value>
</property>
<property>
<name>javax.jdo.option.ConnectionUserName</name>
<value>hive</value>
</property>
<property>
<name>javax.jdo.option.ConnectionPassword</name>
<value>hive</value>
</property>
</configuration>
安装 MySQL，本例中使用的是 MariaDB。
sudo yum install -y mariadb-server
sudo systemctl start mariadb
登录 MySQL，初始无密码，创建 Hive 用户并设置密码。
mysql -uroot
MariaDB [(none)]> create user'hive'@'localhost' identified by 'hive';
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]> grant all privileges on *.* to hive@localhost identified by 'hive';
Query OK, 0 rows affected (0.00 sec)
- 运行 Hive
运行 Hive 之前必须保证 HDFS 已经启动，可以使用 start-dfs.sh 来启动，如果之前安装 Hadoop 已启动，此步骤可略过。
从 Hive 2.1 版本开始, 在启动 Hive 之前需运行 SchemaTool 命令来执行初始化操作。
schematool -dbType mysql -initSchema
SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/home/dc2-user/apache-hive-2.3.4-bin/lib/log4j-slf4j-impl-2.6.2.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/home/dc2-user/hadoop-2.7.7/share/hadoop/common/lib/slf4j-log4j12-1.7.10.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
SLF4J: Actual binding is of type [org.apache.logging.slf4j.Log4jLoggerFactory]
Metastore connection URL: jdbc:mysql://localhost:3306/hive?createDatabaseIfNotExist=true
Metastore Connection Driver : com.mysql.jdbc.Driver
Metastore connection User: hive
Starting metastore schema initialization to 2.3.0
Initialization script hive-schema-2.3.0.mysql.sql
Initialization script completed
schemaTool completed
启动 Hive,输入命令 Hive
hive
which: no hbase in (/home/dc2-user/java/jdk1.8.0_191/bin:/home/dc2-user/hadoop-2.7.7/bin:/usr/local/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/usr/local/bin:/home/dc2-user/apache-hive-2.3.4-bin/bin:/home/dc2-user/.local/bin:/home/dc2-user/bin)
SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/home/dc2-user/apache-hive-2.3.4-bin/lib/log4j-slf4j-impl-2.6.2.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/home/dc2-user/hadoop-2.7.7/share/hadoop/common/lib/slf4j-log4j12-1.7.10.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
SLF4J: Actual binding is of type [org.apache.logging.slf4j.Log4jLoggerFactory]
Logging initialized using configuration in file:/home/dc2-user/apache-hive-2.3.4-bin/conf/hive-log4j2.properties Async: true
Hive-on-MR is deprecated in Hive 2 and may not be available in the future versions. Consider using a different execution engine (i.e. spark, tez) or using Hive 1.X releases.
hive>
- 测试 Hive
在 Hive中创建一个数据库并在数据库中创建一个表：
hive> create database hive_datax;
OK
Time taken: 4.137 seconds
hive> use hive_datax;
OK
Time taken: 0.017 seconds
hive> create table hive_datax(id int, name string);
OK
Time taken: 0.5 seconds
可以看到表已经创建成功，向表中输入数据。
hive> insert into hive_datax values(1,'tom');
WARNING: Hive-on-MR is deprecated in Hive 2 and may not be available in the future versions. Consider using a different execution engine (i.e. spark, tez) or using Hive 1.X releases.
Query ID = dc2-user_20181204110438_eb16f016-a5e2-46bf-ad45-123d7f87e727
Total jobs = 3
Launching Job 1 out of 3
Number of reduce tasks is set to 0 since there's no reduce operator
Job running in-process (local Hadoop)
2018-12-04 11:04:43,296 Stage-1 map = 100%, reduce = 0%
Ended Job = job_local1630301164_0001
Stage-4 is selected by condition resolver.
Stage-3 is filtered out by condition resolver.
Stage-5 is filtered out by condition resolver.
Moving data to directory hdfs://10.254.237.61:9000/user/hive/warehouse/hive_datax.db/hive_datax/.hive-staging_hive_2018-12-04_11-04-38_784_3010010078484421565-1/-ext-10000
Loading data to table hive_datax.hive_datax
MapReduce Jobs Launched:
Stage-Stage-1: HDFS Read: 6 HDFS Write: 89 SUCCESS
Total MapReduce CPU Time Spent: 0 msec
OK
Time taken: 5.107 seconds
查看表中数据：
hive> select * from hive_datax;
OK
1 tom
Time taken: 0.191 seconds, Fetched: 1 row(s)
可以看到数据插入成功并且可以正常查询。
4. 在 MySQL 节点安装 MariaDB
MySQL 的安装可以参照 Hive 节点中安装 MariaDB 的步骤，启动完成后，设置 root 密码并开启远程登录：
mysql -uroot
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 2
Server version: 5.5.56-MariaDB MariaDB Server
Copyright (c) 2000, 2017, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MariaDB [(none)]> set password for 'root'@'localhost'=password('******');
MariaDB [(none)]> GRANT ALL PRIVILEGES ON *.* TO 'root'@'%'IDENTIFIED BY '********' WITH GRANT OPTION;
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]> flush privileges;
Query OK, 0 rows affected (0.00 sec)
接下来在创建数据库和将要导入数据的表：
MariaDB [(none)]> create database mysql_datax;
Query OK, 1 row affected (0.00 sec)
MariaDB [(none)]> use mysql_datax;
Database changed
MariaDB [mysql_datax]> create table mysql_datax(id int(10), name varchar(20),primary key(id));
Query OK, 0 rows affected (0.00 sec)
5. DataX 数据同步
在 DataX 节点的操作比较简单，首先要配置 Java 环境变量，可参照前文中的介绍，然后下载 DataX 并解压。
cd /home/dc2-user
wget http://datax-opensource.oss-cn-hangzhou.aliyuncs.com/datax.tar.gz
tar zxvf datax.tar.gz
cd datax
- Hive 到 MySQL 的数据同步，编辑 job 文件：
cd job
vi hive2mysql
{
"job": {
"content": [
{
"reader": {
"parameter": {
"path": "/user/hive/warehouse/hive_datax.db/hive_datax/*",
"defaultFS": "hdfs://10.254.237.61:9000",
"column": [
{
"index": 0,
"type": "long"
},
{
"index": 1,
"type": "string"
}
],
"fileType": "text",
"encoding": "UTF-8",
"fieldDelimiter": "\u0001"
},
"name": "hdfsreader"
},
"writer": {
"parameter": {
"password": "********",
"column": [
"id",
"name"
],
"connection": [
{
"jdbcUrl": "jdbc:mysql://10.254.116.249:3306/mysql_datax",
"table": [
"mysql_datax"
]
}
],
"writeMode": "insert",
"batchSize": 1024,
"username": "root"
},
"name": "mysqlwriter"
}
}
],
"setting": {
"speed": {
"channel": "1"
}
}
}
}
运行 DataX 开始同步数据
python /home/dc2-user/datax/bin/datax.py /home/dc2-user/datax/job/hive2mysql
2018-12-04 16:37:28.809 [job-0] INFO JobContainer - PerfTrace not enable!
2018-12-04 16:37:28.810 [job-0] INFO StandAloneJobContainerCommunicator - Total 1 records, 4 bytes | Speed 0B/s, 0 records/s | Error 0 records, 0 bytes | All Task WaitWriterTime 0.000s | All Task WaitReaderTime 0.000s | Percentage 100.00%
2018-12-04 16:37:28.812 [job-0] INFO JobContainer -
任务启动时刻 : 2018-12-04 16:37:17
任务结束时刻 : 2018-12-04 16:37:28
任务总计耗时 : 11s
任务平均流量 : 0B/s
记录写入速度 : 0rec/s
读出记录总数 : 1
读写失败总数 : 0
如果输出结尾为以上内容，说明数据同步完成，查看 MySQL 中是否有数据。
MariaDB [(none)]> use mysql_datax;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
MariaDB [mysql_datax]> select * from mysql_datax;
+----+------+
| id | name |
+----+------+
| 1 | tom |
+----+------+
1 row in set (0.00 sec)
说明数据同步成功。
- MySQL 到 Hive 的数据同步
首先在 MySQL 节点的 mysql_datax 表插入一条新记录：
MariaDB [mysql_datax]> insert into mysql_datax values(2,'jerry');
Query OK, 1 row affected (0.00 sec)
MariaDB [mysql_datax]> select * from mysql_datax;
+----+-------+
| id | name |
+----+-------+
| 1 | tom |
| 2 | jerry |
+----+-------+
2 rows in set (0.00 sec)
在 DataX 节点编辑 mysql2hive
{
"job": {
"setting": {
"speed": {
"channel": 3
},
"errorLimit": {
"record": 0,
"percentage": 0.02
}
},
"content": [
{
"reader": {
"name": "mysqlreader",
"parameter": {
"writeMode": "insert",
"username": "root",
"password": "********",
"column": [
"id",
"name"
],
"splitPk": "id",
"connection": [
{
"table": [
"mysql_datax"
],
"jdbcUrl": [
"jdbc:mysql://10.254.116.249:3306/mysql_datax"
]
}
]
}
},
"writer": {
"name": "hdfswriter",
"parameter": {
"defaultFS": "hdfs://10.254.237.61:9000",
"fileType": "text",
"path": "/user/hive/warehouse/hive_datax.db/hive_datax/",
"fileName": "test",
"column": [
{
"name": "id",
"type": "int"
},
{
"name": "name",
"type": "string"
}
],
"writeMode": "append",
"fieldDelimiter": "\u0001",
"compress":"gzip"
}
}
}
]
}
}
运行 DataX 同步数据：
python /home/dc2-user/datax/bin/datax.py /home/dc2-user/datax/job/mysql2hive
2018-12-04 20:50:16.375 [job-0] INFO JobContainer - PerfTrace not enable!
2018-12-04 20:50:16.376 [job-0] INFO StandAloneJobContainerCommunicator - Total 2 records, 10 bytes | Speed 1B/s, 0 records/s | Error 0 records, 0 bytes | All Task WaitWriterTime 0.000s | All Task WaitReaderTime 0.000s | Percentage 100.00%
2018-12-04 20:50:16.378 [job-0] INFO JobContainer -
任务启动时刻 : 2018-12-04 20:50:04
任务结束时刻 : 2018-12-04 20:50:16
任务总计耗时 : 11s
任务平均流量 : 1B/s
记录写入速度 : 0rec/s
读出记录总数 : 2
读写失败总数 : 0
如果输出结尾与以上内容一样，说明同步成功，注意这里读出 2 条记录，会把第一条记录再同步一遍。
查看 Hive 表中的内容：
hive> select * from hive_datax;
OK
1 tom
1 tom
2 jerry
可以看到新记录与旧记录都被写入。