https://www.809508860.xyz/tags/replcation/ Recent content in Replcation on Colben Notes Hugo zh-cn Mon, 04 Nov 2019 02:09:29 +0800 https://www.809508860.xyz/post/postgresql-replication/ Mon, 04 Nov 2019 02:09:29 +0800 https://www.809508860.xyz/post/postgresql-replication/ <h2 id="主库配置">主库配置</h2> <ul> <li>修改 postgresql.conf <div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt">1 </span><span class="lnt">2 </span><span class="lnt">3 </span><span class="lnt">4 </span><span class="lnt">5 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-fallback" data-lang="fallback"><span class="line"><span class="cl">listen_address = &#39;*&#39; </span></span><span class="line"><span class="cl">wal_level = replica </span></span><span class="line"><span class="cl">wax_wal_senders = 10 </span></span><span class="line"><span class="cl">wal_keep_segments = 64 </span></span><span class="line"><span class="cl">hot_standby = on </span></span></code></pre></td></tr></table> </div> </div></li> <li>启动主库 postgresql-10 服务 <div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt">1 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-bash" data-lang="bash"><span class="line"><span class="cl">systemctl start postgresql-10 </span></span></code></pre></td></tr></table> </div> </div></li> <li>创建同步账户 <div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt">1 </span><span class="lnt">2 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-sql" data-lang="sql"><span class="line"><span class="cl"><span class="k">create</span><span class="w"> </span><span class="k">user</span><span class="w"> </span><span class="n">replica</span><span class="w"> </span><span class="n">superuser</span><span class="w"> </span><span class="n">password</span><span class="w"> </span><span class="s1">&#39;123456&#39;</span><span class="p">;</span><span class="w"> </span></span></span><span class="line"><span class="cl"><span class="w"></span><span class="c1">-- 这里可以只赋予 replication 权限，后面从库复制初始数据库时使用其他有权限帐号 </span></span></span></code></pre></td></tr></table> </div> </div></li> <li>修改 pg_hba.conf <div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt">1 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-fallback" data-lang="fallback"><span class="line"><span class="cl">host replication replica samenet md5 </span></span></code></pre></td></tr></table> </div> </div></li> </ul> <h2 id="从库配置">从库配置</h2> <ul> <li>停止从库 postgresql-10 服务，清空数据库目录 <div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt">1 </span><span class="lnt">2 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-bash" data-lang="bash"><span class="line"><span class="cl">systemctl stop postgresql-10 </span></span><span class="line"><span class="cl">rm -rf /var/lib/pgsql/10/data/* </span></span></code></pre></td></tr></table> </div> </div></li> <li>从主库复制初始数据库 <div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt">1 </span><span class="lnt">2 </span><span class="lnt">3 </span><span class="lnt">4 </span><span class="lnt">5 </span><span class="lnt">6 </span><span class="lnt">7 </span><span class="lnt">8 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-bash" data-lang="bash"><span class="line"><span class="cl">pg_basebackup <span class="se">\ </span></span></span><span class="line"><span class="cl"><span class="se"></span> -h &lt;主库ip&gt; <span class="se">\ </span></span></span><span class="line"><span class="cl"><span class="se"></span> -U replica <span class="se">\ </span></span></span><span class="line"><span class="cl"><span class="se"></span> -F p <span class="se">\ </span></span></span><span class="line"><span class="cl"><span class="se"></span> -X stream <span class="se">\ </span></span></span><span class="line"><span class="cl"><span class="se"></span> -P -R <span class="se">\ </span></span></span><span class="line"><span class="cl"><span class="se"></span> -D /var/lib/pgsql/10/data/ <span class="se">\ </span></span></span><span class="line"><span class="cl"><span class="se"></span> -l backup_20191104 </span></span></code></pre></td></tr></table> </div> </div><ul> <li>-h 指定连接的数据库的主机名或IP地址</li> <li>-U 指定连接的用户名</li> <li>-F 指定了输出的格式，支持p（原样输出）或者t（tar格式输出）</li> <li>-X 表示备份开始后，启动另一个流复制连接从主库接收WAL日志</li> <li>-P 表示允许在备份过程中实时的打印备份的进度</li> <li>-R 表示会在备份结束后自动生成recovery.conf文件</li> <li>-D 指定备份写入的数据目录,需要与数据库配置的数据库目录一致,初次备份之前从库的数据目录需要手动清空</li> <li>-l 表示指定一个备份的标识</li> </ul> </li> </ul> <h2 id="检查状态">检查状态</h2> <ul> <li>检查从库进程 <div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt">1 </span><span class="lnt">2 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-bash" data-lang="bash"><span class="line"><span class="cl">ps -ef<span class="p">|</span>grep postgres </span></span><span class="line"><span class="cl"><span class="c1"># 可以看到 wal sender 和 receiver process 两个进程</span> </span></span></code></pre></td></tr></table> </div> </div></li> <li>从库为只读模式,无法进行 增/删/改 操作</li> <li>主库查看 replication 客户端 <div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt">1 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-sql" data-lang="sql"><span class="line"><span class="cl"><span class="k">select</span><span class="w"> </span><span class="n">client_addr</span><span class="p">,</span><span class="n">sync_state</span><span class="w"> </span><span class="k">from</span><span class="w"> </span><span class="n">pg_stat_replication</span><span class="p">;</span><span class="w"> </span></span></span></code></pre></td></tr></table> </div> </div></li> </ul>