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读写分离及分布式架构

读写分离及分布式架构

作者: 学Linux的小子 | 来源:发表于2019-08-22 08:45 被阅读0次

    1.atlas 实现读写分离

    1.1 安装ATLAS

    [root@db03 ~]# rpm -ivh Atlas-2.2.1.el6.x86_64.rpm 
    

    1.2 配置

    cd /usr/local/mysql-proxy/conf
    mv test.cnf test.cnf.bak
    
    cat > test.cnf <<EOF
    [mysql-proxy]
    admin-username = user
    admin-password = pwd
    proxy-backend-addresses = 10.0.0.55:3306
    proxy-read-only-backend-addresses = 10.0.0.52:3306,10.0.0.53:3306
    pwds = repl:3yb5jEku5h4=,mha:O2jBXONX098=
    daemon = true
    keepalive = true
    event-threads = 8
    log-level = message
    log-path = /usr/local/mysql-proxy/log
    sql-log=ON
    proxy-address = 0.0.0.0:33060
    admin-address = 0.0.0.0:2345
    charset=utf8
    EOF
    

    1.3 启动atlas

    /usr/local/mysql-proxy/bin/mysql-proxyd test start
    ps -ef |grep proxy
    
    

    1.4 测试读写分离

    [root@db03 ~]# mysql -umha -pmha -h 10.0.0.53 -P 33060
    读: 
    db03 [(none)]>select @@server_id;
    写:
    db03 [(none)]>begin;select @@server_id; commit;
    
    

    1.5 生产授权用户

    例子: root@'10.0.0.%'
    (1) 业务主库中
    db01 [(none)]>grant all on *.* to root@'10.0.0.%' identified by '123';
    
    (2) 将密码加密处理
    cd /usr/local/mysql-proxy/bin
    [root@m01 /usr/local/mysql-proxy/bin]# ./encrypt 123
    3yb5jEku5h4=
    
    (3) 修改配置文件
    vim /usr/local/mysql-proxy/conf/test.cnf 
    pwds = repl:3yb5jEku5h4=,mha:O2jBXONX098=,root:3yb5jEku5h4=
    
    (4) 重启atlas 
    /usr/local/mysql-proxy/bin/mysql-proxyd test restart
    
    
    (5) 用户测试
    [root@db03 ~]# mysql -uroot -p123 -h 10.0.0.61 -P 33060
    
    

    1.6 atlas基础管理

    [root@db03 ~]# mysql -uuser -ppwd -h 10.0.0.61 -P 2345
    [root@db03 ~]# mysql -uuser -ppwd -h 10.0.0.53 -P 2345
    
    db03 [(none)]>select * from help;
    
    (1) 查帮助:
     SELECT * FROM help
    
    (2) 查看节点信息
    
    SELECT * FROM backends ;
    
    (3) 上线和下线节点
    SET OFFLINE $backend_id;
    SET ONLINE $backend_id 
    
    (4) 删除和添加节点
    db03 [(none)]> REMOVE BACKEND 3;
    db03 [(none)]> ADD SLAVE 10.0.0.53:3306;
    
    
    (5) 添加用户和删除用户
    SELECT * FROM pwds;
    REMOVE PWD root;
    ADD PWD root:123
    ADD ENPWD root:3yb5jEku5h4=
    
    
    (6) 持久化配置
    SAVE CONFIG 
    

    =======================================================================

    2. MyCAT基础架构准备

    2.1 环境准备:

    两台虚拟机 db01 db02
    每台创建四个mysql实例:3307 3308 3309 3310
    

    2.2 删除历史环境:

    pkill mysqld
    rm -rf /data/330* 
    mv /etc/my.cnf /etc/my.cnf.bak
    

    2.3 创建相关目录初始化数据

    mkdir /data/33{07..10}/data -p
    mysqld --initialize-insecure  --user=mysql --datadir=/data/3307/data --basedir=/application/mysql
    mysqld --initialize-insecure  --user=mysql --datadir=/data/3308/data --basedir=/application/mysql
    mysqld --initialize-insecure  --user=mysql --datadir=/data/3309/data --basedir=/application/mysql
    mysqld --initialize-insecure  --user=mysql --datadir=/data/3310/data --basedir=/application/mysql
    

    2.4 准备配置文件和启动脚本

    ========db01==============
    cat >/data/3307/my.cnf<<EOF
    [mysqld]
    basedir=/application/mysql
    datadir=/data/3307/data
    socket=/data/3307/mysql.sock
    port=3307
    log-error=/data/3307/mysql.log
    log_bin=/data/3307/mysql-bin
    binlog_format=row
    skip-name-resolve
    server-id=7
    gtid-mode=on
    enforce-gtid-consistency=true
    log-slave-updates=1
    EOF
    
    cat >/data/3308/my.cnf<<EOF
    [mysqld]
    basedir=/application/mysql
    datadir=/data/3308/data
    port=3308
    socket=/data/3308/mysql.sock
    log-error=/data/3308/mysql.log
    log_bin=/data/3308/mysql-bin
    binlog_format=row
    skip-name-resolve
    server-id=8
    gtid-mode=on
    enforce-gtid-consistency=true
    log-slave-updates=1
    EOF
    
    cat >/data/3309/my.cnf<<EOF
    [mysqld]
    basedir=/application/mysql
    datadir=/data/3309/data
    socket=/data/3309/mysql.sock
    port=3309
    log-error=/data/3309/mysql.log
    log_bin=/data/3309/mysql-bin
    binlog_format=row
    skip-name-resolve
    server-id=9
    gtid-mode=on
    enforce-gtid-consistency=true
    log-slave-updates=1
    EOF
    cat >/data/3310/my.cnf<<EOF
    [mysqld]
    basedir=/application/mysql
    datadir=/data/3310/data
    socket=/data/3310/mysql.sock
    port=3310
    log-error=/data/3310/mysql.log
    log_bin=/data/3310/mysql-bin
    binlog_format=row
    skip-name-resolve
    server-id=10
    gtid-mode=on
    enforce-gtid-consistency=true
    log-slave-updates=1
    EOF
    
    cat >/etc/systemd/system/mysqld3307.service<<EOF
    [Unit]
    Description=MySQL Server
    Documentation=man:mysqld(8)
    Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
    After=network.target
    After=syslog.target
    [Install]
    WantedBy=multi-user.target
    [Service]
    User=mysql
    Group=mysql
    ExecStart=/application/mysql/bin/mysqld --defaults-file=/data/3307/my.cnf
    LimitNOFILE = 5000
    EOF
    
    cat >/etc/systemd/system/mysqld3308.service<<EOF
    [Unit]
    Description=MySQL Server
    Documentation=man:mysqld(8)
    Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
    After=network.target
    After=syslog.target
    [Install]
    WantedBy=multi-user.target
    [Service]
    User=mysql
    Group=mysql
    ExecStart=/application/mysql/bin/mysqld --defaults-file=/data/3308/my.cnf
    LimitNOFILE = 5000
    EOF
    
    cat >/etc/systemd/system/mysqld3309.service<<EOF
    [Unit]
    Description=MySQL Server
    Documentation=man:mysqld(8)
    Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
    After=network.target
    After=syslog.target
    [Install]
    WantedBy=multi-user.target
    [Service]
    User=mysql
    Group=mysql
    ExecStart=/application/mysql/bin/mysqld --defaults-file=/data/3309/my.cnf
    LimitNOFILE = 5000
    EOF
    cat >/etc/systemd/system/mysqld3310.service<<EOF
    [Unit]
    Description=MySQL Server
    Documentation=man:mysqld(8)
    Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
    After=network.target
    After=syslog.target
    
    [Install]
    WantedBy=multi-user.target
    [Service]
    User=mysql
    Group=mysql
    ExecStart=/application/mysql/bin/mysqld --defaults-file=/data/3310/my.cnf
    LimitNOFILE = 5000
    EOF
    
    ========db02===============
    cat >/data/3307/my.cnf<<EOF
    [mysqld]
    basedir=/application/mysql
    datadir=/data/3307/data
    socket=/data/3307/mysql.sock
    port=3307
    log-error=/data/3307/mysql.log
    log_bin=/data/3307/mysql-bin
    binlog_format=row
    skip-name-resolve
    server-id=17
    gtid-mode=on
    enforce-gtid-consistency=true
    log-slave-updates=1
    EOF
    cat >/data/3308/my.cnf<<EOF
    [mysqld]
    basedir=/application/mysql
    datadir=/data/3308/data
    port=3308
    socket=/data/3308/mysql.sock
    log-error=/data/3308/mysql.log
    log_bin=/data/3308/mysql-bin
    binlog_format=row
    skip-name-resolve
    server-id=18
    gtid-mode=on
    enforce-gtid-consistency=true
    log-slave-updates=1
    EOF
    cat >/data/3309/my.cnf<<EOF
    [mysqld]
    basedir=/application/mysql
    datadir=/data/3309/data
    socket=/data/3309/mysql.sock
    port=3309
    log-error=/data/3309/mysql.log
    log_bin=/data/3309/mysql-bin
    binlog_format=row
    skip-name-resolve
    server-id=19
    gtid-mode=on
    enforce-gtid-consistency=true
    log-slave-updates=1
    EOF
    
    
    cat >/data/3310/my.cnf<<EOF
    [mysqld]
    basedir=/application/mysql
    datadir=/data/3310/data
    socket=/data/3310/mysql.sock
    port=3310
    log-error=/data/3310/mysql.log
    log_bin=/data/3310/mysql-bin
    binlog_format=row
    skip-name-resolve
    server-id=20
    gtid-mode=on
    enforce-gtid-consistency=true
    log-slave-updates=1
    EOF
    
    cat >/etc/systemd/system/mysqld3307.service<<EOF
    [Unit]
    Description=MySQL Server
    Documentation=man:mysqld(8)
    Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
    After=network.target
    After=syslog.target
    [Install]
    WantedBy=multi-user.target
    [Service]
    User=mysql
    Group=mysql
    ExecStart=/application/mysql/bin/mysqld --defaults-file=/data/3307/my.cnf
    LimitNOFILE = 5000
    EOF
    
    cat >/etc/systemd/system/mysqld3308.service<<EOF
    [Unit]
    Description=MySQL Server
    Documentation=man:mysqld(8)
    Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
    After=network.target
    After=syslog.target
    [Install]
    WantedBy=multi-user.target
    [Service]
    User=mysql
    Group=mysql
    ExecStart=/application/mysql/bin/mysqld --defaults-file=/data/3308/my.cnf
    LimitNOFILE = 5000
    EOF
    
    cat >/etc/systemd/system/mysqld3309.service<<EOF
    [Unit]
    Description=MySQL Server
    Documentation=man:mysqld(8)
    Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
    After=network.target
    After=syslog.target
    [Install]
    WantedBy=multi-user.target
    [Service]
    User=mysql
    Group=mysql
    ExecStart=/application/mysql/bin/mysqld --defaults-file=/data/3309/my.cnf
    LimitNOFILE = 5000
    EOF
    cat >/etc/systemd/system/mysqld3310.service<<EOF
    [Unit]
    Description=MySQL Server
    Documentation=man:mysqld(8)
    Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
    After=network.target
    After=syslog.target
    [Install]
    WantedBy=multi-user.target
    [Service]
    User=mysql
    Group=mysql
    ExecStart=/application/mysql/bin/mysqld --defaults-file=/data/3310/my.cnf
    LimitNOFILE = 5000
    EOF
    
    

    2.5 修改权限,启动多实例

    chown -R mysql.mysql /data/*
    systemctl start mysqld3307
    systemctl start mysqld3308
    systemctl start mysqld3309
    systemctl start mysqld3310
    
    mysql -S /data/3307/mysql.sock -e "show variables like 'server_id'"
    mysql -S /data/3308/mysql.sock -e "show variables like 'server_id'"
    mysql -S /data/3309/mysql.sock -e "show variables like 'server_id'"
    mysql -S /data/3310/mysql.sock -e "show variables like 'server_id'"
    
    

    2.6 节点主从规划

    箭头指向谁是主库
        10.0.0.51:3307    <----->  10.0.0.52:3307
        10.0.0.51:3309    ------>  10.0.0.51:3307
        10.0.0.52:3309    ------>  10.0.0.52:3307
    
        10.0.0.52:3308  <----->    10.0.0.51:3308
        10.0.0.52:3310  ----->     10.0.0.52:3308
        10.0.0.51:3310  ----->     10.0.0.51:3308
    

    2.7 分片规划

    shard1:
        Master:10.0.0.51:3307
        slave1:10.0.0.51:3309
        Standby Master:10.0.0.52:3307
        slave2:10.0.0.52:3309
    shard2:
        Master:10.0.0.52:3308
        slave1:10.0.0.52:3310
        Standby Master:10.0.0.51:3308
        slave2:10.0.0.51:3310
    

    2.8 开始配置

    shard1
    10.0.0.51:3307    <----->  10.0.0.52:3307
    db02
    mysql  -S /data/3307/mysql.sock -e "grant replication slave on *.* to repl@'10.0.0.%' identified by '123';"
    mysql  -S /data/3307/mysql.sock -e "grant all  on *.* to root@'10.0.0.%' identified by '123'  with grant option;"
    
    db01
    mysql  -S /data/3307/mysql.sock -e "CHANGE MASTER TO MASTER_HOST='10.0.0.52', MASTER_PORT=3307, MASTER_AUTO_POSITION=1, MASTER_USER='repl', MASTER_PASSWORD='123';"
    mysql  -S /data/3307/mysql.sock -e "start slave;"
    mysql  -S /data/3307/mysql.sock -e "show slave status\G"
    
    db02
    mysql  -S /data/3307/mysql.sock -e "CHANGE MASTER TO MASTER_HOST='10.0.0.51', MASTER_PORT=3307, MASTER_AUTO_POSITION=1, MASTER_USER='repl', MASTER_PASSWORD='123';"
    mysql  -S /data/3307/mysql.sock -e "start slave;"
    mysql  -S /data/3307/mysql.sock -e "show slave status\G"
    
    10.0.0.51:3309    ------>  10.0.0.51:3307
    db01
    mysql  -S /data/3309/mysql.sock  -e "CHANGE MASTER TO MASTER_HOST='10.0.0.51', MASTER_PORT=3307, MASTER_AUTO_POSITION=1, MASTER_USER='repl', MASTER_PASSWORD='123';"
    mysql  -S /data/3309/mysql.sock  -e "start slave;"
    mysql  -S /data/3309/mysql.sock  -e "show slave status\G"
    
    10.0.0.52:3309    ------>  10.0.0.52:3307
    db02
    mysql  -S /data/3309/mysql.sock -e "CHANGE MASTER TO MASTER_HOST='10.0.0.52', MASTER_PORT=3307, MASTER_AUTO_POSITION=1, MASTER_USER='repl', MASTER_PASSWORD='123';"
    mysql  -S /data/3309/mysql.sock -e "start slave;"
    mysql  -S /data/3309/mysql.sock -e "show slave status\G"
    
    shard2
    10.0.0.52:3308  <----->    10.0.0.51:3308
    db01
    mysql  -S /data/3308/mysql.sock -e "grant replication slave on *.* to repl@'10.0.0.%' identified by '123';"
    mysql  -S /data/3308/mysql.sock -e "grant all  on *.* to root@'10.0.0.%' identified by '123'  with grant option;"
    
    db02
    mysql  -S /data/3308/mysql.sock -e "CHANGE MASTER TO MASTER_HOST='10.0.0.51', MASTER_PORT=3308, MASTER_AUTO_POSITION=1, MASTER_USER='repl', MASTER_PASSWORD='123';"
    mysql  -S /data/3308/mysql.sock -e "start slave;"
    mysql  -S /data/3308/mysql.sock -e "show slave status\G"
    
    db01
    mysql  -S /data/3308/mysql.sock -e "CHANGE MASTER TO MASTER_HOST='10.0.0.52', MASTER_PORT=3308, MASTER_AUTO_POSITION=1, MASTER_USER='repl', MASTER_PASSWORD='123';"
    mysql  -S /data/3308/mysql.sock -e "start slave;"
    mysql  -S /data/3308/mysql.sock -e "show slave status\G"
    
    10.0.0.52:3310    ----->       10.0.0.52:3308
    db02
    mysql  -S /data/3310/mysql.sock -e "CHANGE MASTER TO MASTER_HOST='10.0.0.52', MASTER_PORT=3308, MASTER_AUTO_POSITION=1, MASTER_USER='repl', MASTER_PASSWORD='123';"
    mysql  -S /data/3310/mysql.sock -e "start slave;"
    mysql  -S /data/3310/mysql.sock -e "show slave status\G"
    
    10.0.0.51:3310  ----->     10.0.0.51:3308
    db01
    mysql  -S /data/3310/mysql.sock -e "CHANGE MASTER TO MASTER_HOST='10.0.0.51', MASTER_PORT=3308, MASTER_AUTO_POSITION=1, MASTER_USER='repl', MASTER_PASSWORD='123';"
    mysql  -S /data/3310/mysql.sock -e "start slave;"
    mysql  -S /data/3310/mysql.sock -e "show slave status\G"
    

    2.9 检测主从状态

    mysql -S /data/3307/mysql.sock -e "show slave status\G"|grep Running:
    mysql -S /data/3308/mysql.sock -e "show slave status\G"|grep Running:
    mysql -S /data/3309/mysql.sock -e "show slave status\G"|grep Running:
    mysql -S /data/3310/mysql.sock -e "show slave status\G"|grep Running:
    

    2.10 如果中间出现错误,在每个节点进行执行以下命令(2.9 状态正确,忽略此步骤)

    mysql -S /data/3307/mysql.sock -e "stop slave; reset slave all;"
    mysql -S /data/3308/mysql.sock -e "stop slave; reset slave all;"
    mysql -S /data/3309/mysql.sock -e "stop slave; reset slave all;"
    mysql -S /data/3310/mysql.sock -e "stop slave; reset slave all;"
    

    3. Mycat的安装

    3.1 安装java环境

    yum install -y java
    

    3.2 上传到/application 并解压

    3.3 软件介绍

    conf: 
    schema.xml    主配置文件
    rule.xml      分片策略定义文件
    server.xml    mycat服务有关的配置
    xxxx.txt      分片参数功能有关
    

    3.4 启动mycat

    [root@db02 ~]# vim /etc/profile 
    export PATH=/application/mycat/bin:$PATH
    source /etc/profile
    
    [root@db02 ~]# mycat start 
    [root@db02 ~]# mysql -uroot -p123456 -h 10.0.0.52 -P8066
    
    

    4. 测试数据准备

    db01:

    mysql -S /data/3307/mysql.sock 
    grant all on *.* to root@'10.0.0.%' identified by '123';
    source /root/world.sql
    
    mysql -S /data/3308/mysql.sock 
    grant all on *.* to root@'10.0.0.%' identified by '123';
    source /root/world.sql
    

    5. 核心配置文件使用介绍(schema.xml)

    5.1 逻辑库定义

    <schema name="TESTDB" checkSQLschema="false" sqlMaxLimit="100" dataNode="sh1"> 
    </schema>  
    ##5.2 数据节点定义
            <dataNode name="sh1" dataHost="oldguo1" database= "world" />    
    ##5.3 数据主机定义
            <dataHost name="oldguo1" maxCon="1000" minCon="10" balance="1"  writeType="0" dbType="mysql"  dbDriver="native" switchType="1">    
                    <heartbeat>select user()</heartbeat>  
            <writeHost host="db1" url="10.0.0.51:3307" user="root" password="123"> 
                            <readHost host="db2" url="10.0.0.51:3309" user="root" password="123" /> 
            </writeHost> 
            </dataHost>  
    

    6. Mycat实现读写分离功能

    [root@db02 /application/mycat/conf]# cat schema.xml
    <?xml version="1.0"?>
    <!DOCTYPE mycat:schema SYSTEM "schema.dtd">  
    <mycat:schema xmlns:mycat="http://io.mycat/">
    <schema name="TESTDB" checkSQLschema="false" sqlMaxLimit="100" dataNode="sh1"> 
    </schema>  
            <dataNode name="sh1" dataHost="oldguo1" database= "world" />         
            <dataHost name="oldguo1" maxCon="1000" minCon="10" balance="1"  writeType="0" dbType="mysql"  dbDriver="native" switchType="1">    
                    <heartbeat>select user()</heartbeat>  
            <writeHost host="db1" url="10.0.0.51:3307" user="root" password="123"> 
                            <readHost host="db2" url="10.0.0.51:3309" user="root" password="123" /> 
            </writeHost> 
            </dataHost>  
    </mycat:schema>
    

    重启生效:

    [root@db02 /application/mycat/conf]# mycat restart
    

    测试:

    [root@db02 /application/mycat/conf]# mysql -uroot -p123456 -h 10.0.0.52 -P8066
    mysql> select @@server_id;
    mysql> begin; select @@server_id;commit;
    

    7. 读写分离+高可用功能

    [root@db01 conf]# mv schema.xml schema.xml.rw
    [root@db01 conf]# vim schema.xml
    <?xml version="1.0"?>  
    <!DOCTYPE mycat:schema SYSTEM "schema.dtd">  
    <mycat:schema xmlns:mycat="http://io.mycat/">
    <schema name="TESTDB" checkSQLschema="false" sqlMaxLimit="100" dataNode="sh1"> 
    </schema>  
        <dataNode name="sh1" dataHost="oldguo1" database= "world" />  
        <dataHost name="oldguo1" maxCon="1000" minCon="10" balance="1"  writeType="0" dbType="mysql"  dbDriver="native" switchType="1"> 
            <heartbeat>select user()</heartbeat>  
        <writeHost host="db1" url="10.0.0.51:3307" user="root" password="123"> 
                <readHost host="db2" url="10.0.0.51:3309" user="root" password="123" /> 
        </writeHost> 
        <writeHost host="db3" url="10.0.0.52:3307" user="root" password="123"> 
                <readHost host="db4" url="10.0.0.52:3309" user="root" password="123" /> 
        </writeHost>        
        </dataHost>  
    </mycat:schema>
    
    
    真正的 writehost:负责写操作的writehost  
    standby  writeHost  :和readhost一样,只提供读服务
    
    当写节点宕机后,后面跟的readhost也不提供服务,这时候standby的writehost就提供写服务,
    后面跟的readhost提供读服务
    
    测试:
    mysql -uroot -p123456 -h 127.0.0.1 -P 8066
    show variables like 'server_id';
    读写分离测试
    mysql -uroot -p -h 127.0.0.1 -P8066
    show variables like 'server_id';
    show variables like 'server_id';
    show variables like 'server_id';
    begin;
    show variables like 'server_id';
     
    对db01 3307节点进行关闭和启动,测试读写操作
    
    

    8. 配置中的属性介绍:(了解一下)

    balance属性
    负载均衡类型,目前的取值有3种: 
    1. balance="0", 不开启读写分离机制,所有读操作都发送到当前可用的writeHost上。 
    2. balance="1",全部的readHost与standby writeHost参与select语句的负载均衡,简单的说,
      当双主双从模式(M1->S1,M2->S2,并且M1与 M2互为主备),正常情况下,M2,S1,S2都参与select语句的负载均衡。 
    3. balance="2",所有读操作都随机的在writeHost、readhost上分发。
    
    writeType属性
    负载均衡类型,目前的取值有2种: 
    1. writeType="0", 所有写操作发送到配置的第一个writeHost,
    第一个挂了切到还生存的第二个writeHost,重新启动后已切换后的为主,切换记录在配置文件中:dnindex.properties . 
    2. writeType=“1”,所有写操作都随机的发送到配置的writeHost,但不推荐使用
    
    switchType属性
    -1 表示不自动切换 
    1 默认值,自动切换 
    2 基于MySQL主从同步的状态决定是否切换 ,心跳语句为 show slave status 
    
    datahost其他配置
    <dataHost name="localhost1" maxCon="1000" minCon="10" balance="1"  writeType="0" dbType="mysql"  dbDriver="native" switchType="1"> 
    
    maxCon="1000":最大的并发连接数
    minCon="10" :mycat在启动之后,会在后端节点上自动开启的连接线程
    
    tempReadHostAvailable="1"
    这个一主一从时(1个writehost,1个readhost时),可以开启这个参数,如果2个writehost,2个readhost时
    <heartbeat>select user()</heartbeat>  监测心跳
    

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