事件起因:近期有研发反应,某数据库从08切换到12环境后,不定期出现写操作提交延迟的问题; 事件分析:在排除了系统资源争用等问题后,初步分析可能由于网络抖动导致同步模式alwayson节点经常出现会话超时等待提交的问题导致。 经过排查,扩展事件里发现不
事件起因:近期有研发反应,某数据库从08切换到12环境后,不定期出现写操作提交延迟的问题;
事件分析:在排除了系统资源争用等问题后,初步分析可能由于网络抖动导致同步模式alwayson节点经常出现会话超时等待提交的问题导致。
经过排查,扩展事件里发现不定期出现35202错误,这是一条副本连接恢复的消息。
由于机房网络环境复杂,数据库服务器和应用服务器混用一个交换机,在业务高峰期时,因上联端口流量打满而导致连接失败的情况屡有发生。
既然短期内无法改造网络环境,那就从SQLSERVER服务器自身出发,只对数据同步的部分进行改造;
现有环境:
SQL AG:为两节点的同步模式,两个节点各有一块网卡连接到交换机,没有直连心跳线(WSFC也不再要求有独立的心跳网络)
改造方案:
1、两个节点各启用一块网卡,采用直连方式进行通信,同时配置私有地址
Server_A:10.0.0.11
Server_B:10.0.0.12
2、删除两个节点的endpoint,手动重新创建Listener_IP为直连IP的endpoint
3、更改AG中,每个副本的endpoint_url
4、等待数据重新同步;
其中第三步的脚本如下,要在两个节点上分别操作,注意Listener_IP为直连网卡的IP
<span> 1</span> <span>/*</span><span>***** Object: Endpoint [Hadr_endpoint] Script Date: 2015/1/6 16:06:17 *****</span><span>*/</span> <span> 2</span> <span>DROP</span> ENDPOINT <span>[</span><span>Hadr_endpoint</span><span>]</span> <span> 3</span> <span>GO</span> <span> 4</span> <span> 5</span> <span>/*</span><span>***** Object: Endpoint [Hadr_endpoint] Script Date: 2015/1/6 16:06:17 *****</span><span>*/</span> <span> 6</span> <span>CREATE</span> ENDPOINT <span>[</span><span>Hadr_endpoint</span><span>]</span> <span> 7</span> STATE<span>=</span><span>STARTED </span><span> 8</span> <span>AS</span> TCP (LISTENER_PORT <span>=</span> <span>5022</span>, LISTENER_IP <span>=</span> (<span>10.0</span>.<span>0.11</span><span>)) </span><span> 9</span> <span>FOR</span> DATA_MIRRORING (ROLE <span>=</span> <span>ALL</span>, AUTHENTICATION <span>=</span><span> WINDOWS NEGOTIATE </span><span>10</span> , ENCRYPTION <span>=</span><span> REQUIRED ALGORITHM AES) </span><span>11</span> <span>GO</span>View Code
第四步的脚本如下,在主副本执行即可
<span>1</span> <span>ALTER</span> AVAILABILITY <span>GROUP</span> <span>[</span><span>Alwayson01</span><span>]</span> <span>2</span> MODIFY REPLICA <span>ON</span> N<span>'</span><span>Node_01</span><span>'</span> <span>WITH</span> (ENDPOINT_URL <span>=</span> N<span>'</span><span>TCP://10.0.0.11:5022</span><span>'</span><span>) </span><span>3</span> <span>4</span> <span>ALTER</span> AVAILABILITY <span>GROUP</span> <span>[</span><span>Alwayson01</span><span>]</span> <span>5</span> MODIFY REPLICA <span>ON</span> N<span>'</span><span>Node_02</span><span>'</span> <span>WITH</span> (ENDPOINT_URL <span>=</span> N<span>'</span><span>TCP://10.0.0.12:5022</span><span>'</span>)View Code
注意:删除endpoint后两副本即为未同步状态,但侦听器和AG组中的数据库不受影响,对应用而言,主副本的服务仍然正常;
参考文章:
http://blogs.msdn.com/b/alwaysonpro/archive/2013/11/01/configuring-a-dedicated-network-for-replicating-changes-from-primary-to-secondary-replica.aspx

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