如何设计和配置MySQL主从数据库以支持LDAP认证的主从复制？

MySQL主从数据库设计_配置ldap主从

背景介绍

在现代企业应用中，数据存储和访问的可靠性、可扩展性和安全性是至关重要的，为了实现高可用性、负载均衡和容灾，许多企业采用MySQL主从复制技术，轻量目录访问协议（LDAP）作为一种集中式的身份认证及目录服务，可以与MySQL结合使用，提供更加安全和便捷的用户管理，本文将详细介绍如何设计和配置MySQL主从复制，并集成LDAP进行用户身份验证。

一、MySQL主从复制简介

1 什么是MySQL主从复制？

MySQL主从复制是指一台MySQL服务器（称为主服务器，Master）将其数据更改（如插入、更新和删除操作）复制到另一台或多台MySQL服务器（称为从服务器，Slave），这种架构可以提高数据的可用性和读取性能，同时还能减轻主服务器的压力。

2 主从复制的作用与优点

数据冗余与恢复：通过主从复制，可以实现数据的冗余备份，当主服务器发生故障时，可以快速切换到从服务器，减少停机时间。

读写分离：主服务器处理写操作，从服务器处理读操作，提高系统的并发处理能力。

负载均衡：将查询请求分配到多个从服务器，降低单个服务器的负载。

数据同步：确保主从服务器之间的数据一致性。

3 主从复制的原理

MySQL的主从复制主要依赖于二进制日志（Binary Log），主服务器将所有修改数据的SQL语句记录到二进制日志中，从服务器通过读取这些日志并将它们在自己的数据库中执行，以保持与主服务器的数据一致。

二、MySQL主从复制的搭建步骤

1 准备工作

在进行主从复制配置之前，需要做好以下准备工作：

确保主服务器和从服务器的MySQL版本一致。

确保主服务器和从服务器之间网络通畅，能够相互通信。

在主服务器和从服务器上创建用于复制的用户，并授予适当的权限。

备份主服务器和从服务器的数据，以防出现错误。

2 配置主服务器

2.2.1 修改配置文件

在主服务器上，打开MySQL配置文件my.cnf，通常位于/etc/my.cnf或/etc/mysql/my.cnf，添加或修改以下内容：

[mysqld]
serverid = 1         # 设置服务器ID，主服务器必须有一个唯一的ID
logbin = mysqlbin   # 启用二进制日志
binlogdodb = your_database_name # 指定需要记录二进制日志的数据库

>your_database_name为需要复制的数据库名称，如果需要对所有数据库进行复制，可以使用alldatabases选项。

2.2.2 重启MySQL服务

保存配置文件后，重启MySQL服务以使配置生效：

sudo systemctl restart mysqld

或者

sudo service mysqld restart

2.2.3 创建复制用户并授权

登录到MySQL控制台，创建一个用于从服务器连接的复制用户，并授予相应的权限：

CREATE USER 'replica_user'@'%' IDENTIFIED BY 'password';
GRANT REPLICATION SLAVE, REPLICATION CLIENT ON *.* TO 'replica_user'@'%';
FLUSH PRIVILEGES;

2.2.4 锁定表并备份数据

为确保数据一致性，在导出数据之前锁定表：

FLUSH TABLES WITH READ LOCK;

使用mysqldump工具备份数据：

mysqldump u root p alldatabases masterdata > master_backup.sql

备份完成后，释放锁：

UNLOCK TABLES;

3 配置从服务器

2.3.1 修改配置文件

在从服务器上，同样打开MySQL配置文件my.cnf，并添加或修改以下内容：

[mysqld]
serverid = 2         # 设置服务器ID，从服务器必须有一个唯一的ID
relaylog = relaybin  # 启用中继日志
logbin = mysqlbin    # 启用二进制日志
readonly = 1          # 设置为只读

2.3.2 重启MySQL服务

保存配置文件后，重启MySQL服务：

sudo systemctl restart mysqld

或者

sudo service mysqld restart

2.3.3 导入数据备份

将从主服务器导出的备份文件复制到从服务器，并导入：

mysql u root p < master_backup.sql

2.3.4 配置复制关系

登录到从服务器的MySQL控制台，执行以下命令以启动复制进程：

CHANGE MASTER TO
    MASTER_HOST='主服务器IP',
    MASTER_USER='replica_user',
    MASTER_PASSWORD='password',
    MASTER_LOG_FILE='mysqlbin.00000X',
    MASTER_LOG_POS= XXX;

主服务器IP、replica_user、password、mysqlbin.00000X和XXX需要根据实际情况替换，可以通过以下命令查看主服务器的状态以获取相关信息：

SHOW MASTER STATUS;

2.3.5 启动复制线程并检查状态

启动从服务器的复制线程，并检查复制状态：

START SLAVE;
SHOW SLAVE STATUS G;

如果Slave_IO_Running和Slave_SQL_Running都显示Yes，则表示复制配置成功。

三、集成LDAP进行用户身份验证

1 安装OpenLDAP

在集成LDAP之前，需要在服务器上安装OpenLDAP，以下是安装步骤：

sudo aptget update
sudo aptget install slapd ldaputils

2 配置OpenLDAP

3.2.1 添加对象类模块

编辑LDAP配置文件ldap.conf，通常位于/etc/ldap/ldap.conf，添加以下内容以支持MySQL用户映射：

moduleload back_hdb.la
moduleload syncprov.la

3.2.2 配置后台数据库HDB

编辑hdb.ldif文件，定义后台数据库的配置：

dn: olcDatabase={1}mdb, objectClass: top objectClass: olcDatabaseConfig objectClass: olcHdbConfig
olcDatabase: {1}mdb
olcDbDirectory: /var/lib/ldap/mdb
olcSuffix: "dc=example,dc=com"
olcRootDN: cn=admin,dc=example,dc=com
olcRootPW: secret
olcDbIndex: uid eq, entryCSN eq:dn presence
olcLastModified: TRUE
olcSyncUseSoft: FALSE
olcSyncRepl: TRUE
olcSyncNoLocal: FALSE

3.2.3 初始化后台数据库

运行以下命令以初始化后台数据库：

sudo ldapadd Y EXTERNAL H ldapi:/// f db.ldif
sudo ldapadd x D cn=admin,dc=example,dc=com W f hdb.ldif

3.2.4 配置syncrepl模块

编辑syncrepl.ldif文件，定义syncrepl的配置：

dn: olcOverlay={0}syncrepl objectClass: olcOverlayConfig objectClass: olcSyncreplConfig olcOverlay: {0}syncrepl olcSyncreplLog: /var/log/ldap/syncrepl.log olcSyncreplProvider: ldap://localhost:389/ ou=syncrepl,cn=admin,dc=example,dc=com olcSyncreplMode: refreshOnly olcSyncreplScope: subtree olcSyncreplScheme: simple olcSyncreplRwUserDN: cn=admin,dc=example,dc=com olcSyncreplRwUserPassword: secret olcSyncreplRwAttrs: ["uid"] olcSyncreplRwOptions: allowreplacespecifyattrs olcSyncreplConsumerTimeout: 60 olcSyncreplDetectObjectClass: both olcSyncreplDetectAddAttributes: entryUUID objectClass olcSyncreplDetectConflicts: ignore olcSyncreplDetectDelete: yes olcSyncreplDetectDeleteConflicts: ignore olcSyncreplDetectModify: yes olcSyncreplDetectModifyConflicts: ignore olcSyncreplDetectSearchBases: yes olcSyncreplRefreshInterval: 60 olcSyncreplRefreshOnly: TRUE olcSyncreplRefreshDelete: TRUE olcSyncreplIgnoreErrors: ignore olcSyncreplFailHard: no olcSyncreplFailSoft: no olcSyncreplFailFast: no olcSyncreplUIDNumber: uidNumber olcSyncreplGIDNumber: gidNumber olcSyncreplGECOSuffix: gecosuffix olcSyncreplUIDRange: uidRange olcSyncreplGIDRange: gidRange olcSyncreplEntryDN: entryDN olcSyncreplEntryCSN: entryCSN olcSyncreplEntryUUID: entryUUID olcSyncreplEntrySeeAlso: entrySeeAlso olcSyncreplMetaCN: metaCN olcSyncreplMetaCSN: metaCSN olcSyncreplMetaSeeAlso: metaSeeAlso olcSyncreplMetaUID: metaUID olcSyncreplMetaGID: metaGID olcSyncreplMetaDescription: metaDescription olcSyncreplMetaGECOSuffix: metaGECOSuffix olcSyncreplMetaUIDNumber: metaUIDNumber olcSyncreplMetaGIDNumber: metaGIDNumber olcSyncreplMetaNCName: metaNCName olcSyncreplMetaRelAuxiliaryObjectClass: metaRelAuxiliaryObjectClass olcSyncreplMetaStructuralObjectClass: metaStructuralObjectClass olcSyncreplMetaEntryUUID: metaEntryUUID olcSyncreplMetaSeeAlso: metaSeeAlso olcSyncreplMetaOwner: metaOwner olcSyncreplMetaGeneration: metaGeneration olcSyncreplMetaHostedOrganization: metaHostedOrganization olcSyncreplMetaHasChildOrganizationalUnit: metaHasChildOrganizationalUnit olcSyncreplMetaSupportsTerminalRenaming: metaSupportsTerminalRenaming olcSyncreplMetaSupportsPagination: metaSupportsPagination olcSyncreplMetaSupportsDynamicGroups: metaSupportsDynamicGroups olcSyncreplMetaSupportsExtensions: metaSupportsExtensions olcSyncreplMetaSupportsSAMLBasedAuthzDecisions: metaSupportsSAMLBasedAuthzDecisions olcSyncreplMetaSupportsSASLBasedAuthzDecisions: metaSupportsSASLBasedAuthzDecisions olcSyncreplMetaSupportsAuthorizationPolicies: metaSupportsAuthorizationPolicies olcSyncreplMetaSupportsAuthorizationPolicyDecisionPoint: metaSupportsAuthorizationPolicyDecisionPoint olcSyncreplMetaSupportsAuthorizationPolicyEnforcementPoint: metaSupportsAuthorizationPolicyEnforcementPoint olcSyncreplMetaSupportsAuthorizationPolicyDecisionPointAssertion: metaSupportsAuthorizationPolicyDecisionPointAssertion olcSyncreplMetaSupportsAuthorizationPolicyEnforcementPointAssertion: metaSupportsAuthorizationPolicyEnforcementPointAssertion olcSyncreplMetaSupportsAuthorizationPolicyAuditLogging: metaSupportsAuthorizationPolicyAuditLogging olcSyncreplMetaSupportsAuthorizationPolicyAuditProvenance: metaSupportsAuthorizationPolicyAuditProvenance olcSyncreplMetaSupportsAuthorizationPolicyAuditAccountability: metaSupportsAuthorizationPolicyAuditAccountability olcSyncreplMetaSupportsAuthorizationPolicyAuditChainOfCustody: metaSupportsAuthorizationPolicyAuditChainOfCustody olcSyncreplMetaSupportsAuthorizationPolicyAuditNonRepudiation: metaSupportsAuthorizationPolicyAuditNonRepudiation olcSyncreplMetaSupportsAuthorizationPolicyAuditDelegatedProofOfControl: metaSupportsAuthorizationPolicyAuditDelegatedProofOfControl olcSyncreplMetaSupportsAuthorizationPolicyAuditBindingOfDuty: metaSupportsAuthorizationPolicyAuditBindingOfDuty olcSyncreplMetaSupportsAuthorizationPolicyAuditObligationOfCare: metaSupportsAuthorizationPolicyAuditObligationOfCare olcSyncreplMetaSupportsAuthorizationPolicyAuditSeparationOfDuty: metaSupportsAuthorizationPolicyAuditSeparationOfDuty olcSyncreplMetaSupportsAuthorizationPolicyAuditPriorNoticeOfCollection: metaSupportsAuthorizationPolicyAuditPriorNoticeOfCollection olcSyncreplMetaSupportsAuthorizationPolicyAuditPriorConsentToCollection: metaSupportsAuthorizationPolicyAuditPriorConsentToCollection olcSyncreplMetaSupportsAuthorizationPolicyAuditOnwardTransfer: metaSupportsAuthorizationPolicyAuditOnwardTransfer olcSyncreplMetaSupportsAuthorizationPolicyAuditSubjectNotification: metaSupportsAuthorizationPolicyAuditSubjectNotification olcSyncreplMetaSupportsAuthorizationPolicyAuditAccessRequestEntitySet: metaSupportsAuthorizationPolicyAuditAccessRequestEntitySet olcSyncreplMetaSupportsAuthorizationPolicyAuditAccessRequestEntityDisclosureSet: metaSupportsAuthorizationPolicyAuditAccessRequestEntityDisclosureSet olcSyncreplMetaSupportsAuthorizationPolicyAuditAccessRequestEntityEaselSet: metaSupportsAuthorizationPolicyAuditAccessRequestEntityEaselSet olcSyncreplMetaSupportsAuthorizationPolicyAuditAccessRequestEntityDPIASet: metaSupportsAuthorizationPolicyAuditAccessRequestEntityDPIASet olcSyncreplMetaSupportsAuthorizationPolicyAuditAccessRequestEntityDPIPSet: metaSupportsAuthorizationPolicyAuditAccessRequestEntityDPIPSet olcSyncreplMetaSupportsAuthorizationPolicyAuditAccessRequestEntityDPISSet: metaSupportsAuthorizationPolicyAuditAccessRequestEntityDPISSet olcSyncreplMetaSupportsAuthorizationPolicyAuditAccessRequestEntityDPITSet: metaSupportsAuthorizationPolicyAuditAccessRequestEntityDPITSet olcSyncreplMetaSupportsAuthorizationPolicyAuditAccessRequestEntityDPIUSet: metaSupportsAuthorizationPolicyAuditAccessRequestEntityDPIUSet olcSyncreplMetaSupportsAuthorizationPolicyAuditAccessRequestEntityDPIUUSet: metaSupportsAuthorizationPolicyAuditAccessRequestEntityDPIUUSet olcSyncreplMetaSupportsAuthorizationPolicyAuditAccessRequestEntityDPOSet: metaSupportsAuthorizationPolicyAuditAccessRequestEntityDPOSet olcSyncreplMetaSupportsAuthorizationPolicyAuditAccessRequestEntityDPSSet: metaSupportsAuthorizationPolicyAuditAccessRequestEntityDPSSet og```
3.2.5 启动LDAP服务并测试
启动LDAP服务，并使用ldapsearch命令测试配置：

sudo systemctl start slapd

ldapsearch x LLL b "dc=example,dc=com" H ldap:///uid=admin

如果返回正确的信息，则表示LDAP配置成功。
3.3 配置MySQL使用LDAP进行身份验证
要使MySQL使用LDAP进行身份验证，需要安装MySQL的auth_ldap插件，并进行相应配置，以下是详细步骤：
3.3.1 下载并安装auth_ldap插件
下载auth_ldap插件源码：

wget https://github.com/mysql/mysqlsystools/archive/refs/heads/auth_ldap.zip O auth_ldap.zip

unzip auth_ldap.zip d /tmp/auth_ldap && cd /tmp/auth_ldap/plugin/auth_ldap/ra_ldap_sasl/auth_ldap.cc

编译插件：

g++ shared fPIC o auth_ldap.so I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr/include/openldap2.4 I/usr/include lldap_r lz lpthread lm ldl o auth_ldap.so shared fPIC I/usr/include/mysql I/usr/include/mysql/mast I/usr/include/mysql/zlib I/usr及以下包括的内容。