ManagingReplication•Chapter9 427 6. Select the Warnings tab (see Figure 9.16). 7. Click the Configure Alerts… button and you will see the screen in Figure 9.17. Figure 9.17 Configure Replication Alerts Figure 9.16 Replication Monitor Warnings 428 Chapter9•ManagingReplication 8. Select the alert you want to configure and click the Configure button. 9. You will be taken to the Alert configuration windows. 10. In the General page you can configure the Error Message and enable the alert. 11. In the Response tab, you can configure the operation, who should receive this alert, and the means of the notification, whether it is an email, pager, or net-sent message. Performance Monitor Most DBAs are using Performance Monitor (perfmon) as a monitoring tool. Perfmon is a not only a SQL Server but also a Windows monitoring tool that has counter objects to monitor various SQL Server counters. The important thing about the Performance Monitor is that you have the option of using integrating with Profiler. There are five performance counter objects to monitor SQL Server replication using perfmon: Replication Agents, Replication Distribution, Replication Log Read, Replication Merge, and Replication Snapshot. Replication Agents There is only one counter in this counter object—Running. Running can be used to measure the number of replication agents currently running. You can select the specific agent as shown in Figure 9.18. Figure 9.18 Replication Agent Counter Object ManagingReplication•Chapter9 429 You can see from the image in Figure 9.18 that you have the option of selecting the following replication agents: Distribution, Logreader, Merge, Queuereader, and Snapshot. This counter is important when you want to measure whether all the replication agents are running. Replication Distribution This counter object provides information about the data delivery between distribution and subscriber (Figure 9.19). Figure 9.19 Replication Distribution Counter Object There are three counters for the Replication Distribution. Delivered Cmds measures the number of commands per second delivered to the subscriber. Delivered Trans/Sec measures the number of transactions per second delivered to the subscriber. Delivery Latency measures current amount of time, in milliseconds, elapsed from when transactions are delivered to the Distributor to when they are applied at the Subscriber. You can select the needed subscriber from the instance list. This counter is important to measure the performance between distributor and subscriber. Replication Logread This counter group is to monitor transactional replication. This counter has the same counters as the Replication Distribution Counter group but it measures from Publisher to Distributor. Replication Merge This counter group consists of three counters, Conflicts/Sec, Downloaded Changes/Sec, and Uploaded Changes/Sec. Conflicts/Sec measures the number of conflicts per second occurring during the merge process. Conflicts will happen if you haven’t configured 430 Chapter9•ManagingReplication conflict resolution. This counter is to measure the conflicts. Downloaded Changes/Sec measures the number of rows per second merged from the Publisher to the Subscriber, and Uploaded Changes/Sec measures the number of rows per second merged from the Subscriber to the Publisher. The last two counters are to measure the load of the merge replication. By integrating Performance Monitor with profiler, you can find the queries from when the merge replication load was high. Replication Snapshot This counter group consists of two counters, Delivered Cmds/Sec and Delivered Trans/ Sec. Delivered Cmds/Sec measures the number of commands per second delivered to the Distributor and Delivered Trans/Sec measures the number of transactions per second delivered to the Distributor. DMVs DMVs were introduced with SQL Server 2005. There are few DMVs that are related to Replication. The sys.dm_os_performance_counters DMV will list the performance counters with their current values. By including a like operator to object_name field as listed here, you can view the current values for all replication counters and for their instances. SELECT * FROM sys.dm_os_performance_counters WHERE object_name LIKE '%replication%' There are four DMVs that are related to replication. They are sys.dm_repl_articles, sys.dm_repl_schemas, sys.dm_repl_tranhash, and sys.dm_repl_traninfo. You can use these DMVs to gather information about replication. Te s T Da y Tip When you need to select the monitoring option between Performance Monitor and Replication Monitor for replication, you need to choose perfmon when you want to gather data for some duration. Also, in Replication Monitor you don’t have an option for logging data, which is available with perfmon. ManagingReplication•Chapter9 431 Summary of Exam Objectives In this chapter we discussed Replication in SQL Server 2008. We covered the roles of Publisher, Subscriber, and Distributor. There are three main different types of replication, Snapshot, Transactional, and Merge. We compare them with the features and usages of each replication type. Replication monitoring is important because you need to monitor whether your replication is responding to your configurations. Exam Objectives Fast Track Replication Scenarios Publication consists of articles that are database objects that need to Ü publish. Distributor is responsible for distributing data between Publisher and Ü Subscriber. Subscriber can be considered as the end user who will receive the data of Ü the article that Publisher publishes. Replication Types There are three main types of replication; Snapshot, Transactional, and Ü Merge replication are used in different situations. Peer-to-Peer Replication is a transactional replication that can be used Ü when you need to replicate the entire contents of the database. With SQL Server 2008, Peer-to-Peer Replication has the feature of conflict resolution. Replication Configuration You need to create an initial snapshot for all replications. Ü All the main configuration for replication is almost identical; each has Ü minor changes. When you are configuring Peer-to-Peer Replication, first you have to Ü configure Transactional Replication and enable the Peer-to-Peer Replication. . only a SQL Server but also a Windows monitoring tool that has counter objects to monitor various SQL Server counters. The important thing about the Performance Monitor is that you have the option. Error Message and enable the alert. 11. In the Response tab, you can configure the operation, who should receive this alert, and the means of the notification, whether it is an email, pager,. merged from the Subscriber to the Publisher. The last two counters are to measure the load of the merge replication. By integrating Performance Monitor with profiler, you can find the queries