Chapter 10 Protecting Virtual Environments

Chapter 10 Protecting Virtual Environments

164 - Protecting Virtual Environments As more datacenters move to virtualize their environments and the number of virtual machines and the physical hosts they run on grows, a comprehensive protection strategy is required to ensure proper protection. This is a complex problem as the number of virtual machines continues to increase and their backup windows continue to shrink. The following chapter describes various strategies for protecting virtual environments using the Simpana Virtual Server Agent (VSA) and standard file system and application agents. Note: This is a guide for planning and designing strategies for protecting virtual environments. This is not a detailed engineering guide and CommVault STRONGLY recommends working with CommVault to properly plan, implement, and optimize Simpana for your virtual environment. Simpana Virtual Protection Methods There are two primary methods CommVault software can use to protect virtual environments: 1. Virtual Server Agent (VSA) 2. idataagents installed within virtual machines Which method is best to use depends on the virtual infrastructure, type of virtual machines being protected and the data contained within the virtual machines. In most cases using the Virtual Server Agent will be the preferred protection method. For specific virtual machines using an idataagent inside the VMs will be the preferred method. In other cases using a combination of both the VSA and idataagents in the VMs could be used.

Protecting Virtual Environments - 165 The following table highlights basic capabilities and limitations for using the Virtual Server Agent and idataagents. Feature / Capability Virtual Server Agent idataagent in VM Overview Provides disk level protection with granular browse and recovery. For VMware backups volume and file/folder protection is also supported. Backs up data using agent communication directly to file system or application. This method for protecting VMs operates just like a physical client in a CommCell environment. Recovery performance of virtual machine Provides fast recovery performance by recovering entire disk files. Using full system restore or 1-Touch for VM recovery. This process would be slower than restoring virtual disks with VSA since it would be an object level restore. Recovery of virtual disk volumes Volume level restores only in VMware. For Xen and Hyper-V file level browse and recovery would be used to recover full volumes. Browse and restore or restore by job if volume was defined as separate subclient. Granular browse capability Granular browse is possible by indexing virtual machines at time of backup. Indexing VM backups is enabled by default. Provides the same browse and recovery features as a physical client. All agent capabilities are supported when installed in VM. Application Protection Only provides crash consistent protection of application data. Scripts can be used to quiesce application data prior to VSA backup for application consistent protection. Provides application consistent protection for database and log files by directly communicating with application to properly quiesce data. Application protection with SnapProtect option Provides application consistent snapshot and backup protection for MS-SQL and Exchange. Provides full integration with SnapProtect feature for application consistent snapshot and backup protection on all supported idataagents.

166 - Protecting Virtual Environments Crash Consistent and Application Consistent Protection When choosing to use the Virtual Server Agent and/or idataagents inside of VMs it is important to consider what is being protected. The state of the data at the time of backup is critical to be able to properly restore the data. There are two possible states that data can be in at the time of backup, Crash Consistent or Application Consistent. Crash Consistent Crash Consistent backups are based on point-in-time snapshot and backup operations of a virtual machine that allows the VM to be restored to the point in which it was snapped. When the snapshot occurs all blocks on the virtual disks are frozen for a consistent point-in-time view. There are several issues when performing crash consistent snapshot and backup operations. The first issue is that if an application is running on the virtual machine it is not aware the snapshot is being taken. VSA communicates with the hosting hypervisor to initiate snapshots at the VM level and there is no communication with the application. Any I/O processes being conducted by the application will continue without any knowledge that the snap has been performed. This may cause issues if a VM hosting an application has high disk I/O activity at the time the snap occurred. The other issue is data integrity. Crash consistent means when a snap occurs, a logical view of the virtual disk block structure is preserved for the backup operation. The crash consistent view would be the same as if you turned the power off on an application server without properly shutting down the application. In this case, maintenance may need to be performed on the application databases before they would be usable and there is the possibility of data corruption. Crash consistent backups can work well for disk volumes containing file data but this is not recommended for protecting application databases. Crash Consistent backup performs a snapshot and backup of the disk at a point in time. The application is not aware that this is being performed and data integrity is not guaranteed.

Application Consistent Protecting Virtual Environments - 167 With Application Consistent protection, the application itself is aware that it is being snapped. This awareness allows for the data to be protected and restored in a consistent and usable state. Application aware protection works by communicating with the application to quiesce data or by using scripts to properly quiesce the data. Application consistent protection is not critical for file data but is absolutely critical for application databases. There are three methods to provide application consistent protection: Simpana application idataagents An idataagent installed in the VM will directly communicate with application running in the VM. Prior to the snap operation the agent will communicate with the application to properly quiesce databases. For large databases this is the preferred method for providing application consistent point in time snap and backup operations. Using application agents in the VM also provide database and log backup operations and a simplified restore method using the standard browse and recovery options in the CommCell GUI. Scripting database shutdowns Using external scripts which can be inserted in the Pre/Post processes of a subclient, application data can be placed in an offline state to allow for a consistent point-in-time snap and backup operation. This will require the application to remain in the offline state for the entire time of the snapshot operation. When the VM is recovered the application will have to be restarted after the restore operation completes. This method is only recommended when Simpana agents are not available for the application. VSA and SnapProtect For Microsoft SQL and Exchange virtual machines, application aware protection can be performed using the VSA agent and Simpana SnapProtect feature. This concept requires additional configurations and is covered in detail in the SnapProtect chapter. Application Consistent backup performs a snapshot and backup of the application data at a specified point in time. The application is aware that this is being performed and will quiesce data.

168 - Protecting Virtual Environments Agent Based Protection Agent based protection uses Simpana idataagents installed directly in the virtual machine. When an agent is installed in the VM, it will appear in the CommCell console just like a regular client and the functionality will be exactly the same as an agent installed on a physical host. The main advantage with this configuration is that all the features available with Simpana agents can be used to protect data on the VM. For applications, using idataagents provide complete application awareness of all data protection operations. When using idataagents in VMs, data will be backed up through a Media Agent to protected storage. The Media Agent can be locally installed on the virtual machine if the machine has direct access to storage or data can be moved over the network to a dedicated Media Agent. Agent based VM protection installs Simpana agents directly in the VM. This allows file systems and applications to be protected using all the features Simpana agents offer.

Protecting Virtual Environments - 169 One issue when using idataagents in virtual machines is when the virtual machine needs to be restored. Since the idataagent protects all data at the object level, the machine will need to be restored object by object. Compare this method to using the VSA backup process which can restore the entire virtual machine at the disk level. When protecting large databases which are backed up as single objects, idataagents can be a good solution. When backing up file servers with large amounts of smaller objects, idataagents within the virtual machine would not be a good solution. With Simpana v9 Client Side Deduplication, data moved over the network is dramatically reduced once the first full backup is completed. This provides an efficient method of backing up large amounts of data and is recommended to improve backup performance when using agents inside of VMs. It s important to note that when using client side deduplication in a virtual machine, all blocks will be hashed on the client. This processing will be done using the hosting server s resources which may negatively impact performance when too many VMs are being backed up concurrently. Carefully consider on which VMs you want to use idataagents and schedule backup operations during off-peak hours when physical hosts have adequate resources to process and protect data. File System idataagents To protect an entire virtual machine or specific volumes on a VM, using the VSA is the preferred protection method. If the VM only requires specific files or folders to be protected, or if specific data on the VM requires special protection requirements such as scripting or filtering, a File System idataagent can be used. In the following example a mission critical subclient has been defined to protect a small amount of data on a virtual machine. The virtual machine is not required for protection since a template can be used to recreate the VM in the event of full system failure. Using this method on VMs with small amounts of data requiring protection can improve overall performance by reducing the total amount of data that must be protected. Granular Application Agents Granular application agents provide the ability to protect objects within an application database providing granular processing of application data. For example, Exchange data can be protected at the mailbox level by

170 - Protecting Virtual Environments using the Simpana Mailbox idataagent, Mailbox Archiving idataagent, or Compliance Archiving idataagent. Each one of these agents provides object level protection that provides individual object recovery, content indexing, or ediscovery search capabilities. Data protected by these agents can also be independently managed by subclients providing data lifecycle management capabilities that are not possible with the VSA agent. Database Application Agents Simpana database agents provide advanced protection features that would not be available when using VSA. Separate protection of database and logs can be performed. Options to truncate logs or replay logs to a specific point in time can be used to better manage database protection. Using database idataagents in virtual machines provides application consistent database protection and is a preferred protection method. The following diagram illustrates the use of agents in a virtual machine to provide application consistent database and log backups. Using this method can allow for shorter Recovery Point Objectives (RPOs) since log files can frequently be backed up throughout the day. This level of granular protection is not possible when using the VSA agent alone. Virtual Server Agent (VSA)

Protecting Virtual Environments - 171 The Simpana Virtual Server Agent (VSA) interacts with the hosting hypervisor to provide protection at the virtual machine level. This means agents do not need to be installed directly on the virtual machines, although installing restore-only idataagents will provide a simplified method for restoring data back to the VM. Simpana software currently supports VMware, Hyper-V, and Xen server with the Virtual Server Agent. Depending on the hypervisor application being used and the virtual machine s operating system, different features and capabilities will be available. The Simpana VSA interfaces with the hypervisor s APIs and provides capabilities inherent to the application. As hypervisor capabilities improve, the Simpana VSA agent will be enhanced to take advantage of new capabilities. Backup Levels Virtual machines are protected by VSA by invoking the hypervisor application to snap the VM. When the snapshot is taken the VM can be backed up in a crash consistent point it time state. The VSA can backup machines at the disk, volume, or file level depending on the hypervisor s capabilities. The following table shows support at various backup levels: Application Disk Level Volume Level File Level VMware YES YES YES Hyper-V YES NO NO XEN Server YES NO NO Disk Level Disk level backups will protect all disks for a virtual machine and VM boot data. The entire VM can be recovered and optionally automatically turned on after recovery. For VMware, disk volumes can also be independently recovered. If Enable Granular Recovery is selected in Advanced Backup Options, files and folders can be browsed and recovered. Volume Level Volume level backups allow you to select which virtual disks to backup. This is currently only supported with VMware. This is best used when only specific data volumes need to be protected. System drives backed up at the volume level will not be bootable with a direct restore of the volume. To select which volumes will be backed up, use the subclient Filters tab to filter out volumes not to be backed up. File Level File level backups allow individual folders or files to be protected. Consider using this on virtual machines where a base image can be retained and only small amounts of data changes on a regular basis. Use the Filter tab to filter out all data that does not require protection. Use the Filter exceptions to define data that does require

172 - Protecting Virtual Environments protection. For example: Filter the C:\ drive and set an exception rule for C:\Users. This will only backup the Users folder on the C drive. When a file level backup is configured, the entire volume that contains the files or folders is snapped. During the data movement process the VSA will filter out data that does not require protection. Because of this process, it would be recommended to install a File System idataagent on the VM if only a small portion of a large volume requires protection. How VSA Works VSA works by communicating with the hosting hypervisor to initiate software snapshots of virtual machines. Once the VMs are snapped, VSA will back them up to protected storage. The following steps are used to protect VMs in a virtual environment: 1. CommServe server communicates with VSA to initiate a data protection job. 2. VSA communicates with the hypervisor application to request software snapshots for virtual machines defined in the subclient. 3. The hypervisor will quiesce the virtual machines and perform software snapshots of the VMs. 4. The virtual application will communicate back to VSA that the VMs have been quiesced. 5. VSA will back up the virtual machines to CommVault protected storage. 6. If configured the virtual machines will be indexed for granular browse and recovery of objects in the virtual disks. 7. VSA will then communicate back to the hosting virtual application that the backup process has completed. 8. The VMs snapshots will then be released.

Protecting Virtual Environments - 173 The following diagram illustrates the VSA software snapshot and backup process in a VMware environment using a VSA proxy server. Hypervisor and VSA Architecture Depending on the hypervisor application various methods can be used to deploy the VSA agent. VMware & VSA When protecting VMware environments different Transport Modes can be used to move VMs to protected storage. There are three primary Transport Modes that can be used: SAN Mode Hot Add Mode NBD (Network Based) Mode Each of these modes has their advantages and disadvantages. Variables such as physical architecture, source data location, ESX resources, network resources and VSA proximity to Media Agents and storage will all have an effect on determining which mode is best to use. It is also recommended to consult with CommVault for design guidance when deploying Simpana software in a VMware environment.

174 - Protecting Virtual Environments SAN Transport Mode can be used on a VSA proxy with direct access to snapshot VMs in the source storage location. This mode can provide a major advantage regarding performance and load reduction on the ESX server. Virtual machines will be backed up through the VSA and to the Media Agent. If the VSA is installed on a proxy server configured as a Media Agent with direct access to storage, LAN-Free backups can be performed. This eliminates data movement through the ESX server and if there is a LAN-Free path to storage, data traffic over the network is eliminated. The following diagram illustrates the ability to use a VSA proxy using SAN Transport Mode when protecting VMware environments. This allows the backup process of virtual machines to be conducted on the proxy server eliminating the load on the ESX servers. If the VSA has direct access to protected storage installing a Media Agent on the proxy will provide LAN-Free backups. Hot Add Mode uses a virtual VSA in the VMware environment. This will require all data to be processed and moved through the VM on the ESX server. Depending on the storage target the Media Agent can also be installed on the virtual machine. Some disk storage and tape libraries in SAN environments cannot be zoned to virtual machines. This configuration would require data to be moved from the virtual VSA to a physical Media Agent during data protection jobs. In certain environments with enough processing power on ESX hosts and a need to consolidate physical hardware using a virtual VSA method could be used. By implementing this method with client side deduplication bandwidth consumption will be greatly reduced after the initial protection of virtual machines. This method will require all data blocks to be hashed and processes on the virtual VSA proxy which will require significant CPU and memory resources. To reduce memory and disk requirements a dedicated LAN based Media Agent can be used for the deduplication database.

Protecting Virtual Environments - 175 The following diagram shows Hot Add Mode VSA proxy being installed as a VM. This method will require all protection processing to be conducted on the virtual machines placing the load on the ESX server.

176 - Protecting Virtual Environments NBD Network Mode will use a VSA proxy installed on a physical host. VSA will connect to VMware and snapshots will be moved from the VMware environment over the network and to the VSA proxy. This method will require adequate network resources and it is recommended to use a dedicated backup network when using the NBD mode. The following diagram illustrates the NBD Transport Mode using a physical VSA proxy to move VM data over the network to protected storage.

Microsoft Hyper-V VSA Protecting Virtual Environments - 177 Microsoft Hyper-V allows the VSA to be installed directly on the hosting server. Data is processed and moved to a Media Agent. If the Hyper-V server has direct access to protected storage, a Media Agent can be installed to provide LAN-Free backups. The following diagram shows the VSA being installed directly on the Hyper-V physical server.

178 - Protecting Virtual Environments Xen Server VSA The VSA agent is installed on a dedicated virtual machine hosted on the Xen server. Data is processed by the VSA and moved to a Media Agent. The following diagram shows the VSA installed on a virtual machines in the Xen environment.

Protecting Virtual Environments - 179 Hardware Snapshots with SnapProtect The Simpana v9 SnapProtect feature provides integration with hardware vendors or Simpana s Continuous Data Replicator (CDR) to conduct, manage, and backup snapshots. This technology can be used to snap VMs at the data store level and back them up to protected storage. The process for protecting virtual machines is similar to performing snapshots with the VSA agent directly interfacing with the hosting hypervisor application. VSA will first quiesce the virtual machine and then the SnapProtect feature will use vendor API s to perform a hardware snapshot of the data store. The data store will then be mounted on an ESX proxy and all VMs registered. The VMs can then be backed up and indexes generated for granular level recovery. The snapshots can also be maintained for live browse and recovery. The backup copies can be used for longer term retention and granular browse and recovery. The following diagram illustrates SnapProtect and VSA integration. VSA will communicate with the hypervisor to quiesce VMs that will be protected. After the VMs are in quiescent state the SnapProtect feature will initiate a hardware snapshot by communicating with hardware through APIs. Once the snap process is complete the ESX proxy will mount the snap and the VSA agent will backup VMs.

180 - Protecting Virtual Environments Using the VSA and SnapProtect agent provides a high availability, disaster recovery, and data recovery solution. Specific configuration and hardware are required to implement this solution method. For more information on SnapProtect configurations and VSA see the SnapProtect chapter. Application Data on Raw Device Mapping (RDM) Volumes When the VSA agent protects VMware virtual machines it can perform disk, volume, or file level software snapshots of VMDK files. It will not protect any volumes using RDM. This can be used as an advantage when designing solutions for protecting large databases. A VSA agent will be used to snap and backup the virtual disks as VMDK files but will skip RDM volumes. An application agent can then be installed in the VM and subclients can be configured to protect databases on RDM volumes. The application idataagent will provide communication to provide consistent point-in-time backups of application data. Configuring the Virtual Server Agent Once the Virtual Server Agent is installed on the physical or virtual host, there are several components that need to be configured: Instances are used to connect to the virtual environment. Depending on the hypervisor application, different instance options will be available. Backup Sets are used to define how virtual machines will be discovered and managed. The available options will be based on the hypervisor application being used. Subclients are used to define which virtual machines will be protected and depending on the hypervisor application different subclient settings will be available. Instances When the Virtual Serve Agent is initially installed, instances will have to be configured. The VSA can be configured with different instances to manage multiple virtual environments through a single master VSA client. Using a master VSA will provide greater flexibility and simplified administration in large virtual environments. One or more instances can be configured for Hyper-V, Xen, or VMware. For VMware the instance can be configured for VCenter or an ESX host. Multiple instances can be defined for each of the three hypervisors.

Protecting Virtual Environments - 181 The following diagram shows three VSA instances. Two instances are for VMware VCenter and the third is for Hyper-V. Backup Set The backup set is used to configure the discovery methods for virtual machines. For VMware it can also be used to select vstorage or VCB for protection types depending on the version of VMware being used. By default the protection mode will automatically be detected. This process will first attempt to use vstorage APIs and will fail back to VCB if vstorage is not available.

182 - Protecting Virtual Environments Backup sets can be configured for VMware, Hyper-V and Xen. Depending on the hypervisor defined in the instance specific options will be available in the backup set properties.

Discovery Rules for VMware Protecting Virtual Environments - 183 For VMware discovery rules can be configured based on how virtual machines will be grouped when configuring subclients. When a discovery rule is selected an Auto Discover tab will be enabled in the subclient to correspond to the rule selected. For example, if the discovery rules are set to data store affinity, the Auto Discover tab will allow the selection of specific data stores the subclient can use when discovering and protecting virtual machines. Depending on the VMware infrastructure and methods used to protect VMs, proper configuration of discovery rules and subclients will provide greater scalability and backup performance. In the following example the SnapProtect feature is being used to mount data stores to back up virtual machines. A subclient is used to define VMs from different data stores requiring all data stores to be mounted prior to VM backup operations. This design can have a negative impact on backup performance and may degrade performance in the production environment.

184 - Protecting Virtual Environments This illustration shows multiple data stores, each defined in a separate subclient. When a backup job runs for the subclient only one data store will require mounting.

Protecting Virtual Environments - 185 Subclients Subclients are used to define the virtual machines that will be protected. Virtual machines are defined within a specific subclient by discovering virtual machines within the backup set. This is done in the Content tab by selecting the Discover button. Virtual machines can be assigned to different subclients using the Subclient Name drop down box. The virtual machines can also be set to Do not back up. Depending on the hypervisor application, different methods can be used to configure subclient content for virtual machines. The following diagram shows three subclients. The default subclient will discover and manage any virtual machines not associated with any custom subclients. A mission critical and an IT system subclient will be used to group and manage virtual machines. Auto Discover for VMware Based on the discovery rules in a VMware backup set, the Auto Discover tab will be used to determine the source for virtual machine discovery. The Auto Discover tab can be defined with one or more sources for the VMs. Sources such as data store affinity, ESX server affinity, or match host name by regular expressions, etc can be configured. Using auto discovery modes will allow VM groupings into different subclients to provide better organization and scalability of VM protection. Depending on the VMware architecture specific modes are recommended to provide the best overall performance. In large VMware environments CommVault professional services should be involved to ensure proper configuration and scaling.

186 - Protecting Virtual Environments Data Readers Data readers determine the number of concurrent VM backups that will run for a subclient. The default number of readers is 1. Each virtual machine will back up as a single stream so increasing the data readers will allow multiple VMs to be snapped and backed up concurrently. Consider disk performance, disk I/O and network bandwidth before modifying this setting. Setting this number too high could result in poor backup performance and may cause snapshots to fail. The following example shows three subclients each set to use three data readers. If the subclients are backed up at the same time, a total number of nine concurrent streams will be used.

Use Proxy (VMware) Protecting Virtual Environments - 187 VMware VSA allows physical proxy servers to be used when backing up virtual machines. This provides for greater scalability in larger virtual environments by using multiple VSA proxies to protect VMs. The subclient option Use Proxy is used to assign a specific proxy to the subclient. This allows the CommVault administrator to configure an entire VMware environment from a single spot when multiple VSA proxies are being used. When a VSA agent is installed on a proxy, each proxy will appear in the CommCell console. By using a master VSA, a single configuration point can be used to configure the entire virtual environment. This greatly simplifies administration since a single backup set can be used on the master VSA preventing virtual machines from being defined in multiple subclients. This is based on the CommVault coded rule that data is mutually exclusive to the subclient in which it is defined within a backup set. If configurations were done on each VSA proxy individually they would all contain their own backup sets which could result VMs being protected multiple time. The following diagram shows three Media Agent / VSA proxies being used to protect virtual machines. Three subclients are being used, each one directed to use a different proxy.

188 - Protecting Virtual Environments Backup Type For Hyper-V and Xen server all virtual machines are snapped and protected at the disk level. For VMware protection can be provided at the disk, volume, or file level. VMware backup type selection for disk, volume or file level can be set for each subclient. Consider the following before configuring this option: Only disk level snapshots are bootable immediately after restore. For volume level snapshots us the Filters tab to exclude volumes from backup. File level snapshots will snap the entire volume but only back up selected files/folder. In this case it may be preferred to use a file system agent in the virtual machine to back up just the required data. Only virtual disk files will be protected with the VSA backup. Raw Device Mapping (RDM) volumes will not be backed up. Transport Mode for VMware Depending on the location of the VSA a subclient allows specific transport modes to be selected. For a virtual VSA the Hot Add mode will be used, for a physical VSA with SAN access to snapshots the SAN mode will be used and for a network based VSA the NBD (network) mode will be used.

Protecting Virtual Environments - 189 The following diagram illustrates the three primary transport modes that can be configured for a subclient. Depending on access to storage Media Agent software can also be installed on the VSA server. SnapProtect Operations When integrating the SnapProtect feature with supported hardware snapshot disk technologies, the VSA, SnapProtect and supported hardware all integrate for virtual machine protection. Select the snap engine to be used in the SnapProtect Operations tab. Once the hardware snap has been taken it can be mounted on an ESX proxy and backed up to protected storage. This method is used when performing application consistent backups of Exchange or SQL virtual machines. The proxy is specified in the Proxy ESX Server configuration box. The Application aware backup for granular recovery option can be enabled and the option to truncate exchange logs can also be selected to provide full application awareness and log truncation for Exchange virtual servers. For more information on snapshots in virtual environments see the SnapProtect Technology chapter.

190 - Protecting Virtual Environments Enable Granular Recovery During the backup of the virtual machines, indexes can be generated from disk metadata. This allows for granular browse and recovery of objects within the virtual machine. The option Enable Granular Recovery in the Advanced Backup options is used to determine if indexes will be generated. This setting is enabled by default. CommVault recommends using the granular recovery option for all virtual machines. To provide in-place recovery of objects into the virtual machine, a Restore Only idataagent can be installed on the virtual machine. Enable Granular Recovery is used to generate indexes during backup operations of virtual machines. This setting is enabled by default.

Protecting Virtual Environments - 191 VSA Backup Performance Before discussing methods for improving virtual machine backups it is important to note that CommVault can only move data as fast as the physical environment will allow. The virtual architecture, network bandwidth, and storage performance all play key roles in VM backup performance. Ensure that the environment is adequately scaled to meet protection windows. Consult with CommVault prior to deploying Simpana software in a virtual environment. Consider the following key points as a basic starting point when addressing protection of a virtual environment: Does the VM require regular protection? How long will the VM be needed for? How often does data on the VM change? Is the data on the VM static or dynamic? Does the entire VM require protection or just specific data? Should the VM be protected with VSA or agents installed in the VM? Understanding Protection Needs Before you start designing your virtual protection strategies you first need to know what it is your protecting and what type of protection is needed. Details of each virtual machine should be documented. A strong Change Management policy is essential, and though IT administrators may dread the enormous amount of documentation they must create and maintain, this information can greatly affect your protection strategies. To properly inventory your virtual environment, consider different virtual machines and the functions they provide. Determine if servers are static or dynamic. Do they provide a unique service, or are there many instances of the same system (such as domain controllers or web servers). Determine if they are production or test and development systems. Documenting the different services these systems provide can later be used to determine protection strategies. Business Function What purpose does the virtual machine serve? Does it serve an IT function such as a Domain Controller or is it a business system such as a document server? If it s a business system, what business unit owns the machine? Is it a production, test, or development server? What other servers is it dependent on? This information will provide guidance on whether the entire VM requires protection using VSA or just specific data on the machine requires protection. Example 1: If a VM approximately 20GB in size only requires protection of a folder 500 MB in size, a file system idataagent may be used to protect the data. If the VM was created from a template it could quickly be recreated. In this case the 500 MB folder is the critical data that requires protection and not the entire VM.

192 - Protecting Virtual Environments Example 2: A business function is running on a VM that provides a service to a department within your organization. The VM is static and no user data is stored in the VM. In this case using the VSA to snap and backup the VM on a weekly or even monthly basis may provide adequate protection. Using a separate subclient to define this VM and other VMs requiring the same protection can be used to set a separate schedule using weekly or monthly intervals. IT Function For IT virtual machines consider its IT function. Is it a static box where data rarely changes? Is it a redundant box for scaling or high availability where other virtual machines provide the same functionality? If other systems depend on the virtual machine, how critical is it that this machine is available. Test & Development Very often when applications are being developed in house, virtual machines are requested for testing or development. This results in requests for machines that may be used for a short time, and then never used again. Keeping track of who requested the machine and how long they need it for is critical in determining whether the machine actually requires protection. CommVault Strategies for Improving VM Backups In most cases using the Virtual Server Agent will provide the best backup and recovery performance. When protecting applications running on virtual servers, application agents installed within the VM can provide better backup and restore performance as well as application consistent protection of database and log files. The following section covers several scenarios that can be used to optimize backup performance in a virtual environment. VSA Protection with Deduplication and DASH Full When using Client Side Deduplication, once an initial full backup is completed only changed blocks will be protected. During an incremental backup, all changed blocks are copied and deduplicated on the VSA server. During a subsequent full backup the entire VM is snapped and backed up through the VSA. Most of the blocks will already exist in storage so network bandwidth and storage requirements will be minimal. However, the entire VM will have to be processed by the VSA. This will require each block for the VM being hashed and compared in the deduplication database. A DASH-Full can be used to eliminate the snap and deduplication process on the VSA. A DASH-Full is actually a Read Optimized Synthetic Full backup. A traditional Synthetic Full would read backup chunks, verify the chunk and write it back to storage in a new location. With deduplication, reading and writing chunks is an unneeded step. Since the data blocks for the VM already exists in storage they would be discarded during the Synthetic Full operation. A DASH-Full updates record information in the deduplication database and generates a new index file to signify the start of a new cycle without actually reading the data. This can significantly reduce backup times when compared to traditional full or synthetic full backups.

Protecting Virtual Environments - 193 The following diagram illustrates using deduplication and DASH Full backups to greatly reduce backup windows and data movement. Once the initial full backup is done, only incremental backups will be run on production data, and DASH Full backups will be used to consolidate cycles for retention and aging purposes. This method provides the ability to protect large amounts of data in very short protection windows.

194 - Protecting Virtual Environments DR Protection Using DASH Copy A primary advantage of server virtualization is the hardware consolidation of data centers. This also makes disaster recovery hot sites more practical. New features in Simpana 9 provide the key components to provide a complete end to end DR solution. DASH-Copy provides the ability to selectively copy deduplicated data between site locations which dramatically reduces bandwidth required to copy data to an alternate site. This operation is more efficient than traditional site replication because only required data blocks at the DR site are copied. This is done by configuring secondary copies and using subclient Associations to copy only relevant data to the DR site. In addition to this functionality, separate retention can be configured for each site. The following diagram shows that using deduplication and DASH copies can provide for a sound disaster recovery solution. Once the initial full is copied to the off-site location, only change blocks will be copied during the DASH copy operations.

Stagger Schedule Subclients Protecting Virtual Environments - 195 In large virtual environments, hundreds or even thousands of virtual machines may require protection. This can make it impractical to meet backup windows. Spreading the backup windows for full and incremental backups over a longer time period can help meet operation windows. To do this create multiple subclients and set different schedules for each subclient to spread full and incremental backups throughout a backup cycle. The following diagram shows seven subclients being used to stagger schedule backups during a weekly cycle. A full backup will be conducted for each subclient based on the different days of the week. Incremental backups will be conducted on the other days of the week. Schedule VSA Agent Subclients FRI SAT SUN MON TUE WED Friday Saturday Sunday Monday Tuesday Wednesday Thursday FULL FULL FULL FULL FULL FULL THU FULL

196 - Protecting Virtual Environments Using Multiple VSA Proxies with VMware In large VMware environments, several VSA proxies can be used to load balance virtual machine backups. Installing VSA on multiple Media Agents will allow more virtual machines to be simultaneously backed up. Careful planning is required based on disk performance to determine how many virtual machines can be snapped and protected at any given time. With Simpana 9 all virtual machines and VSA proxies can be assigned from a master VSA in the CommCell Console. This allows large environments using multiple proxies to be configured in a single location. Each subclient can define its own virtual machines and a different proxy can be configured for each subclient. The following diagram shows three Media Agent / VSA proxies being used to protect virtual machines. Three subclients are being used, each one directed to use a different proxy.

Using an Application idataagent Protecting Virtual Environments - 197 Application agents in virtual machines can be used in certain cases to provide better backup and recovery performance. An application idataagent can be used to provide database and log backups where a VSA agent would backup the VM in its entirety. To limit the amount of data transmitted over the network and storage requirements for duplicate blocks, client side deduplication can be used. Using application agents within the VM will allow full database and log backups to be conducted based on RPO and RTO requirements. A DASH-Copy can be used to copy deduplicated data to an off-site location for disaster recovery purposes. The following diagram shows the use of idataagents inside of virtual machines to provide data protection. Although the VSA is a preferred method for protecting virtual machines, using idataagent in special situations can provide better protection.