ptg6432687 370 12 Application-Level Failover and Disaster Recovery in a Hyper-V Environment FIGURE 12.5 Displaying the network adapters in a cluster network. FIGURE 12.6 Configuring a network to be excluded from cluster use. 7. Right-click Cluster Network 1 and select Rename. Rename the cluster to match the network adapter name. 8. For this example, right-click the renamed iSCSI network and select Properties. 9. Select the Do Not Allow the Cluster to Use This Network radio button, and then click OK, as shown in Figure 12.6. Download at www.wowebook.com ptg6432687 371 Deploying a Failover Cluster for Hyper-V Hosts 12 10. Back in the Failover Cluster Management console, rename the remaining cluster networks and verify that each network is configured for the proper cluster only or cluster and client communication. 11. When all the networking changes are complete, close the Failover Cluster Management console and log off of the server. Adding Nodes to the Hyper-V Host Cluster After the first node of a Hyper-V host cluster has been installed and configured, additional nodes need to be added to the cluster to provide the failover server for the initial node. To add additional nodes after the initial cluster creation process, follow these steps: 1. Log on to one of the Windows Server 2008 cluster nodes with an account with administrator privileges over all nodes in the cluster. 2. Click Start, All Programs, Administrative Tools, and select Failover Cluster Management. 3. When the Failover Cluster Management console opens, if necessary type in the name of the local cluster node to connect to the cluster. 4. When the Failover Cluster Management console connects to the cluster, select and expand the cluster name. 5. Select and expand Nodes in the tree pane. 6. Right-click Nodes and select Add Node. 7. When the Add Node Wizard opens, click Next on the Before You Begin page. 8. In the Select Server page, type in the name of the cluster node and click the Add button. When the node is added to the list, click Next to continue. 9. In the Confirmation page, review the names of the node or nodes that will be added and click Next to continue. 10. When the process completes, review the results in the Summary page, and then click Finish to close the wizard. 11. Close the Failover Cluster Management console and log off of the server. Adding Storage to the Cluster When shared storage is used with failover clusters, all the LUNs or targets presented to the cluster hosts may not have been added to the cluster during the initial configuration. When this is the case, and additional storage needs to be added to the cluster, perform the following steps: 1. Log on to one of the Windows Server 2008 cluster nodes with an account with administrator privileges over all nodes in the cluster. 2. Click Start, All Programs, Administrative Tools, and select Failover Cluster Management. 3. When the Failover Cluster Management console opens, if necessary type in the name of the local cluster node to connect to the cluster. Download at www.wowebook.com ptg6432687 372 12 Application-Level Failover and Disaster Recovery in a Hyper-V Environment FIGURE 12.7 Displaying the local and cluster disks on a cluster node. 4. In the tree pane, select Storage, right-click Storage, and select Add a Disk. 5. If suitable storage is ready to be added to the cluster, it will be listed in the Add Disks to a Cluster window. If a disk is listed, check the box next to the desired disk or disks and click OK to add the disks to the cluster. 6. Once the process completes, if necessary change the drive letter of the new disk. 7. Close the Failover Cluster Management console. 8. Click the Start button and select Computer. 9. Review the list of disks on the cluster node and note that disks managed by the cluster are listed as clustered disks rather than local disks, as shown in Figure 12.7. This is a distinct change from server clusters in Windows Server 2003. 10. Close the Explorer windows and log off of the server. Cluster Quorum Configuration If all of the cluster nodes and the shared storage were available during the creation of the cluster, the best suited quorum model was automatically selected during the cluster- creation process. When the existing cluster quorum is need to be validated or changed, perform the following steps: 1. Log on to one of the Windows Server 2008 cluster nodes with an account with administrator privileges over all nodes in the cluster. 2. Click Start, All Programs, Administrative Tools, and select Failover Cluster Management. 3. When the Failover Cluster Management console opens, if necessary type in the name of the local cluster node to connect to the cluster. 4. In the tree pane, select the cluster name, and in the Tasks pane, the current quorum model will be listed. Download at www.wowebook.com ptg6432687 373 Deploying a Failover Cluster for Hyper-V Hosts 12 FIGURE 12.8 Configuring the cluster quorum mode for a failover cluster. 5. Review the current quorum model. If it is correct, close the Failover Cluster Management console. 6. If the current Quorum model is not the desired model, right-click the cluster name in the tree pane, click More Actions, and select Configure Cluster Quorum Settings. 7. In the Select Quorum Configuration page, select the desired quorum model radio button or select the radio button of the recommended model, and then click Next to continue, as shown in Figure 12.8. 8. If a quorum model contains a witness disk or file share, select the designated disk or specify the path to the file share and click Next. 9. In the Confirmation page, review the settings and click Next to update the cluster quorum model for the failover cluster. 10. Review the results in the Summary page, and then click Finish to return to the Failover Cluster Management console. 11. Close the Failover Cluster Management console and log off of the server. Creating a Virtual Guest Session on the Host Cluster Once the desired cluster configuration is achieved, the cluster is ready for virtual guest sessions to be installed on the host cluster configuration. Follow the steps covered in Chapter 5, “Installing a Guest Session on Hyper-V,” to build the guest session. The steps for creating the guest session on Hyper-V are identical, with the exception of the following areas to note: . Make sure that when the guest session is created, the guest session image is stored on the shared storage of the Hyper-V failover cluster environment. Download at www.wowebook.com ptg6432687 374 12 Application-Level Failover and Disaster Recovery in a Hyper-V Environment . Ensure that the network adapter chosen for the guest session is tied to a physical network adapter, not on a virtual switch specific to the host server system. The virtual guest operating system and application can be installed, and after the guest session is booted and running, install the integration tools for the operating system to make sure the latest drivers and options specific to the operating system have been prop- erly installed. Configuring Start Actions and Making the Virtual Guest Highly Available After the virtual guest session has been installed and configured to operate properly, certain settings need to be configured on the Hyper-V host server to make the virtual guest session highly available, and to set the proper start actions on the guest session. The first step is to configure the automatic start action on the Hyper-V host. The auto- matic start action identifies whether a guest session will automatically start when the host server is started, or whether the guest session will wait until the guest session is manually started after a Hyper-V host server reboot. Normally, if the Hyper-V host server reboots, the administrator wants to make sure the guest sessions also automatically start so that someone does not have to manually intervene to get guest sessions running. With Hyper- V, h o w e v e r, t h e h i g h - a v a i l a b i l i t y f u n c t i o n o f t h e H y p e r - V h o s t s e r v e r c o n f i g u r a t i o n a u t o - matically starts managed guest sessions, because the cluster needs to choose which host node is managing the guest session. You don’t want both hosts trying to turn on or manage the guest session. Therefore, in the case of Hyper-V host failover clustering, the guest session automatic start action is disabled. To configure the automatic start action for a virtual guest session, complete the following steps: 1. Log on to one of the Windows Server 2008 cluster nodes with an account with administrator privileges over all nodes in the cluster. 2. Click Start, All Programs, Administrative Tools, and select Hyper-V Administration to launch the Hyper-V management tool. 3. In the Hyper-V management tool, under Virtual Machines, right-click Failover Test, and then click Settings. 4. In the leftmost pane, click Automatic Start Action. 5. Under What Do You Want This Virtual Machine to Do When the Physical Computer Starts?, click Nothing, and then click Apply. The next step is to make the virtual machines highly available. This is specific to Hyper-V and is the overall failover cluster control that determines which Hyper-V host server is in control of the guest sessions. Windows Server 2008 provides several out-of-box cluster resources that can be used to deploy Windows services and applications using failover clusters for services beyond Hyper-V (including cluster high availability for DHCP servers, file servers, DFS servers, and the like, as shown in Figure 12.9). Download at www.wowebook.com ptg6432687 375 Deploying a Failover Cluster for Hyper-V Hosts 12 FIGURE 12.9 Windows Server 2008 built-in cluster services and applications resources. To select and configure the services or application settings, run the High Availability Wizard as follows: 1. Log on to one of the Windows Server 2008 cluster nodes with an account with administrator privileges over all nodes in the cluster. 2. Click Start, All Programs, Administrative Tools, and select Failover Cluster Management. 3. When the Failover Cluster Management console opens, if necessary type in the name of the local cluster node to connect to the cluster. 4. In the tree pane, select the cluster name, expand it, and select Services and Applications. 5. Right-click Services and Applications and select Configure a Service or Application. 6. In the High Availability Wizard that opens, click Next in the Before You Begin page. 7. Select the Virtual Machine option from the Service or Application page, and click Next to continue. If the Hyper-V role has not been installed yet on each node prior to selecting the desired entry, an error will display, and the process cannot continue. 8. Review the settings in the Confirmation page, and then click Next to deploy the service on the failover cluster. 9. When prompted, click Finish to close the wizard. 10. In the tree pane, expand Services and Applications to reveal the new group, right- click the virtual machine name, and click Bring This Service or Application Online. Doing so brings the virtual machine online and starts the guest session. Download at www.wowebook.com ptg6432687 376 12 Application-Level Failover and Disaster Recovery in a Hyper-V Environment Configuring Failover and Failback Clusters that contain two or more nodes automatically have failover configured for each service or application group as long as each node has the Hyper-V role installed and supports running the group locally. Failback is never configured by default and needs to be manually configured for each service or application group if desired. Failback allows a designated preferred server or “preferred owner” to always run a particular cluster group when it is available. When the preferred owner fails and the affected groups fail over to an alternate node, once the preferred node is back online and functioning as desired the fail- back configuration options are used to determine whether the group will automatically fail back immediately or after a specified period. Also, with regard to failover and failback configuration, the failover and failback properties define how many failures in a specified number of hours will be tolerated before the group is taken offline and remains offline. To review and if necessary change the failover and failback configuration options on a partic- ular service or application group, perform the following steps: 1. Log on to one of the Windows Server 2008 cluster nodes with an account with administrator privileges over all nodes in the cluster. 2. Click Start, All Programs, Administrative Tools, and select Failover Cluster Management. 3. When the Failover Cluster Management console opens, if necessary type in the name of the local cluster node to connect to the cluster. 4. In the tree pane, select the cluster name, expand it, and select Services and Applications. 5. Expand Services and Applications and right-click the desired group and select Properties. For this example, the ABC-CLUSTER-P5 Hyper-V cluster group is used. 6. In the ABC-CLUSTER-P5 group properties on the General tab, in the Preferred Owner section, check the box next to the desired node if failback will be configured. Do not close the group property window. 7. Select the Failover tab and review the number of allowed failures in a specified number of hours. The default is two group failures allowed in six hours. 8. In the lower section of the page, if desired enable failback and configure whether failback will be allowed and whether it will occur immediately when the preferred node is online or if the failback can occur only during after hours, such as between the hours of 9 p.m. and 6 a.m. or 17 and 6, as shown in Figure 12.10. NOTE To reduce the chance of having a group failing back to a node during regular business hours after a failure, configure the failback schedule to allow failback only during non- peak times or after hours using settings similar to those made in Figure 12.10 and based on the organization’s work hours and automated backup schedule. Download at www.wowebook.com ptg6432687 377 Deploying a Failover Cluster for Hyper-V Hosts 12 FIGURE 12.10 Configuring a services or application failover threshold and failback configuration. Testing Failover Clusters After all the desired cluster nodes are added to the failover cluster and failover and fail- back configuration options are set for each service or application group, each group should be verified for proper operation on each cluster node. For these tests to be complete, failover and, when applicable, failback of cluster groups need to be tested. They can be tested by simulating a cluster resource failure or by manually moving the service or application groups between nodes. Testing Ser vices and Applications Groups Using Manual Failover To manually fail over or move a service or application group between failover cluster nodes, perform the following steps: 1. Log on to one of the Windows Server 2008 cluster nodes with an account with administrator privileges over all nodes in the cluster. 2. Click Start, All Programs, Administrative Tools, and select Failover Cluster Management. 3. When the Failover Cluster Management console opens, if necessary type in the name of the local cluster node to connect to the cluster. 4. In the tree pane, select the cluster name, expand it, and select Services and Applications. 5. Expand Services and Applications and select the desired group. For this example, the ABC-CLUSTER-PS Hyper-V server group is used. 6. In the Tasks pane, note the current owner of the group. Download at www.wowebook.com ptg6432687 378 12 Application-Level Failover and Disaster Recovery in a Hyper-V Environment FIGURE 12.11 Moving a service or application group to another available node. 7. In the tree pane, right-click the desired group, select Move This Service or Application to Another Node, and select any of the desired available nodes, as shown in Figure 12.11, for use to move the group to node 2. 8. The group will be moved to the chosen node, and when the group is back online it will be reflected as Status: Online in the Tasks pane. Close the Failover Cluster Management console and log off of the server. Simulating the Failure of a Cluster Resource Simulating a cluster resource failure can be easily accomplished using the Failover Cluster Management console. Each resource will have its own properties, and simulating a failure will usually just initiate the startup or restoration of the resource back to an online state. When the failure threshold is reached, the service or application group will be taken offline, moved to another available node, and brought back online. To simulate the failure of a cluster resource and test the failover of a group, perform the following steps: 1. Log on to one of the Windows Server 2008 cluster nodes with an account with administrator privileges over all nodes in the cluster. 2. Click Start, All Programs, Administrative Tools, and select Failover Cluster Management. 3. When the Failover Cluster Management console opens, if necessary type in the name of the local cluster node to connect to the cluster. 4. In the tree pane, select the cluster name, expand it, and select Nodes. 5. Select More Actions, and then click Stop Cluster Service. Doing so stops the cluster service on the Hyper-V Host server system. Download at www.wowebook.com ptg6432687 379 Deploying a Failover Cluster for Hyper-V Hosts 12 6. The virtual machine service will be moved to the other node of the Hyper-V cluster, with user services remaining operational. Failover Cluster Maintenance Services and applications are deployed on failover cluster based on the fact that they are critical to business operations. The reliability of each cluster node is very important, and making any changes to the software or hardware configuration of each node can compro- mise this reliability. Before any changes are implemented on a production failover cluster, a few premaintenance tasks should be performed. Premaintenance Tasks Before maintenance is run on a cluster node or the entire failover cluster, several tasks should be completed. To prepare a cluster node for maintenance, complete the following steps: 1. Whether you’re planning a software or hardware upgrade, research to see whether the changes will be supported on Windows Server 2008 failover clusters. 2. Log on to one of the Windows Server 2008 cluster nodes with an account with administrator privileges over all nodes in the cluster. 3. Click Start, All Programs, Administrative Tools, and select Failover Cluster Management. 4. When the Failover Cluster Management console opens, if necessary type in the name of the local cluster node to connect to the cluster. 5. In the tree pane, select the cluster name, and in the tree pane note the current host server. If the current host server is the node that will be taken offline for mainte- nance, the cluster will be automatically moved to an alternate node if the mainte- nance node is rebooted. 6. In the tree pane, select and expand Services and Applications to reveal each of the groups. 7. Select each group, and in the Tasks pane, note which node is the current owner of the move. Manually move each group to the node that will remain online if any of the groups are currently running on the node that will be taken offline for maintenance. 8. After all the groups have been moved to a node that will remain online, in the tree pane expand Nodes to reveal all the nodes in the failover cluster. 9. Locate the node that will be taken offline for maintenance, right-click the node, and select Pause. 10. When the node is paused, resources cannot fail over and come online and the system can have the software and hardware configuration or updates applied and, if necessary, rebooted. 11. When the maintenance tasks are complete, the node can be configured to be active in the failover cluster by right-clicking the node in the Failover Cluster Management console and selecting Resume. Download at www.wowebook.com . Expand Services and Applications and right-click the desired group and select Properties. For this example, the ABC-CLUSTER -P5 Hyper-V cluster group is used. 6. In the ABC-CLUSTER -P5 group properties. Applications. 5. Expand Services and Applications and select the desired group. For this example, the ABC-CLUSTER-PS Hyper-V server group is used. 6. In the Tasks pane, note the current owner of the group. . determines which Hyper-V host server is in control of the guest sessions. Windows Server 2008 provides several out-of-box cluster resources that can be used to deploy Windows services and applications