ManagingHighAvailability•Chapter6 207 Once you get the Database Mirroring page on the screen, the first thing you must do is click the Configure Security button. This button will present you with a wizard, which will walk you through the process. The key screens will be shown here, the others merely described. After clicking Next on the introduction page, you are asked if you wish to configure security to include a witness server instance. After clicking Next you are prompted with a page with the Principal and Mirror checked and grayed out with the Witness server either checked or grayed out. If you select No on the first page then this page is skipped. On the next page you are asked to configure the Database Mirroring Endpoint as shown in Figure 6.5. This is the endpoint that will be created on the Principal server that the Mirror instance (and Witness instance) will use to contact the Principal instance. Port 5022 is the default TCP port number, however this port number can be changed to another port number if required. You can also change the Endpoint name if you so desire. Figure 6.4 Database Mirroring Menu 208 Chapter6•ManagingHighAvailability The next page asks you to select the Mirror server instance and set its port number and Endpoint name. If the instances are on different physical servers it is recommended that you use the same port number because this keeps your configuration less complex. If the instances are on the same physical server then you will need to select different port numbers since only one instance at a time can use a single port number. If you have selected to use a Witness then the next page lets you select the instance to use as the Witness instance as well as the port number and name of the endpoint. The same rules about port numbers apply. The next page asks you for the service accounts of the SQL Servers. If the machines are on the same domain, or the domains are trusted, then fill out these fields. If the machines are not on trusted domains, or the machines are not on a domain then leave the fields all blank. If the instances are all on the same machine and are running under a local machine account enter the machine account here. Because our lab machines are on a Windows 2003 domain and the instances are Figure 6.5 Database Mirroring Principle Server Endpoint Configuration ManagingHighAvailability•Chapter6 209 running under domain accounts we enter these accounts in the boxes as shown in Figure 6.6. If you are not configuring a Witness then that field will not appear. From this screen you can click Next or Finish since you have completed the wizard. Doing so will configure the Endpoints and grant the remote instances accounts rights to connect to that Endpoint. Confirm any messages that the wizard gives you. Since you will have the SQL Servers connecting to each other it is recommended that you run the SQL Servers and SQL Server Agents under a domain account. Although this is not required it is recommended, and it makes database mirroring easier to set up and manage. Figure 6.6 Database Mirroring Service Accounts Page After completing the wizard you will be prompted with a screen similar to the one shown in Figure 6.7. 210 Chapter6•ManagingHighAvailability If you select the Do Not Start Mirroring button then database mirroring will not be configured and you will need to reconfigure the Mirror and Partner connection information before you can start database mirroring. If everything goes correctly you should be greeted with a screen like the one shown in Figure 6.8. Figure 6.7 Database Mirroring Confirmation Window Figure 6.8 Database Mirroring Running Correctly ManagingHighAvailability•Chapter6 211 EXERCISE 6.2 SE t t I n g Up Da t a b a S E MI R R o R I n g 1. Set up a database in one instance of SQL Server. 2. Configure database mirroring in High Performance mode. Once database mirroring is running you will notice some additional information in the object explorer when you are connected to the servers that are being mirrored. The Principal database will show the word Principal, and the Mirror will show “Restoring…” next to it. The Principal will also tell you the status of the mirror. In Figure 6.9 we can see that the mirror is synchronized to the Principal. If the mirror is receiving its log updates the principle will report this as well. Figure 6.9 Object Explorer Showing Mirrored Databases . for the service accounts of the SQL Servers. If the machines are on the same domain, or the domains are trusted, then fill out these fields. If the machines are not on trusted domains, or the. Confirm any messages that the wizard gives you. Since you will have the SQL Servers connecting to each other it is recommended that you run the SQL Servers and SQL Server Agents under a domain. Witness then the next page lets you select the instance to use as the Witness instance as well as the port number and name of the endpoint. The same rules about port numbers apply. The next