Understanding EMC Avamar with EMC Data Protection Advisor Applied Technology Abstract EMC Data Protection Advisor provides a comprehensive set of features to reduce the complexity of managing data protection environments, improve compliance with business and regulatory requirements, and reduce the risk of data loss. This white paper outlines how Data Protection Advisor helps you gain control of your Avamar backup environment, by better understanding what is working well and what it not, enabling a proactive approach to managing your environment. March 2010
Copyright 2010 EMC Corporation. All rights reserved. EMC believes the information in this publication is accurate as of its publication date. The information is subject to change without notice. THE INFORMATION IN THIS PUBLICATION IS PROVIDED AS IS. EMC CORPORATION MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND WITH RESPECT TO THE INFORMATION IN THIS PUBLICATION, AND SPECIFICALLY DISCLAIMS IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Use, copying, and distribution of any EMC software described in this publication requires an applicable software license. For the most up-to-date listing of EMC product names, see EMC Corporation Trademarks on EMC.com All other trademarks used herein are the property of their respective owners. Part Number h6108 Applied Technology 2
Table of Contents Executive summary...4 Introduction...4 Audience... 4 DPA licensing with Avamar... 4 EMC Avamar...4 How Avamar works... 5 Data Protection Advisor and Avamar...6 Data collection from Avamar... 6 Improved deduplication reporting... 7 Performance reports... 9 Avamar Replication operations... 10 Avamar Maintenance Jobs... 11 Predictive job scheduling and reconciliation... 12 Deduplication ROI Trend and Cost Savings reports... 13 Conclusion...15 References...15 Applied Technology 3
Executive summary EMC Data Protection Advisor (DPA) collects, monitors, analyzes, and reports on information from the entire data protection infrastructure, providing a unified data protection management window. When EMC Avamar is introduced into an environment, typically there are two or more backup solutions being managed, so DPA eliminates the need for multiple interfaces. EMC Avamar Data Store is a fully integrated, software/hardware, backup and recovery solution that also includes data deduplication. Avamar s deduplication begins at the client to be backed up. Avamar detects subfile-level data changes and backs them up only if they have not already been backed up. This results in only the changed data being moved, enabling savings on time, processing, bandwidth, and storage requirements. The use of EMC Data Protection Advisor enhances the abilities of Avamar monitoring and reporting, through its central historical repository, analysis engine, and robust reporting. Introduction This white paper describes the EMC Avamar technology, including its architecture and various components. It then details how EMC Data Protection Advisor can extend Avamar, showing some of the different options available. Audience This white paper is intended for Data Protection Advisor professionals to provide insight into what Avamar is all about and how Data Protection Advisor reports on it. DPA licensing with Avamar As of DPA 5.0.1, DPA licenses Avamar environments based on the capacity of each grid. Existing DPA/Avamar customers will need to exchange existing client licenses to obtain the needed capacity licenses when they upgrade to Data Protection Advisor 5.0 Service Pack 1. Customers, who use DPA to monitor a variety of backup applications, including Avamar, will require both a DPA Backup Capacity license and Client license. For example, a customer with a 2 TB Avamar grid will require a corresponding 2 TB DPA Backup Capacity license, regardless of the number of Avamar clients. It is not necessary to include any Avamar systems that are managed through an EMC NetWorker server (that is, Avamar defined as a Dedupe node to NetWorker). Avamar clients managed through NetWorker do not require a DPA Backup Capacity license as they are included as clients of the NetWorker server. EMC Avamar As mentioned previously, Avamar s source-based deduplication begins at the client, detecting subfile-level data changes and backing up only changed blocks of data. This results in only the changed data being transmitted over the network for backup and in huge savings on both the time taken to back up and on network bandwidth requirements. A backup client needs to be backed up in full once, and thereafter only changes are backed up to the Avamar Data Store. Each backup job is treated as a full-level backup as Avamar has the ability to recover the client in its entirety from any backup, even though only incremental changes are saved from each backup. Applied Technology 4
Besides deduplicating at the backup client level, Avamar also deduplicates across clients and sites, a process that is also known as Global Deduplication. This means that duplicate data/subfile chunks of data will only be stored once by Avamar. A typical example would be the C:\WINDOWS subdirectory and its contents. This will mainly and wholly be exactly the same across all Windows backup clients and thus Avamar needs to store this only once but allow any client to restore from it. In environments where clients have been virtualized using VMware, Avamar also provides the same significant savings. With traditional backup solutions, virtual machines need to move weekly full and daily incremental backups through the VMware host s physical resources (NIC, CPU memory, and so on), which could then be overloaded and cause backup overruns and breached SLAs. With Avamar, only sending changed segments of data daily can potentially provide a 300 percent daily reduction in network resource usage compared to traditional backups. Avamar also does remote replication over standard WAN connections, thus doing disaster recovery replication without needing to transport tapes from one site to another. For full virtual machine backups, Avamar can also deduplicate data stored in virtual disks (VMware *.vmdk files), significantly reducing storage consumption and enabling replication of virtual disk across congested WANs. How Avamar works Avamar solves the challenge of redundancy in backup data at the source, that is, before transfer across the LAN or WAN during backups. Avamar agents are deployed on the systems to be protected (servers, desktops, laptops) to identify and filter repeated data segments stored in files within a single system and across multiple systems over time. This ensures that each unique data segment is backed up only once across the enterprise. As a result, copied or edited files, shared applications, embedded attachments, and even daily changing databases generate only a small amount of incremental backup data. By moving only new, unique subfile data segments, Avamar reduces the daily network bandwidth required and storage by up to 500x. By storing just a single instance of each subfile data segment globally, Avamar also reduces total back-end disk storage by up to 50x for cost-effective, long-term, disk-based recovery. A key factor for eliminating redundant data at a segment (or subfile) level is the method for determining segment size. Fixed-block or fixed-length segments are commonly employed by snapshot or replication technologies. Unfortunately, even small changes to a dataset (for example, inserting data at the head of the file) can change all fixed-length segments in a dataset. Avamar uses an intelligent method for determining segment size that looks at the data itself to determine logical boundary points, eliminating the inefficiency. Avamar s patented method for segment size determination is designed to yield optimal efficiency across all systems in an enterprise. Avamar s algorithm analyzes the binary structure of a dataset in order to determine segment boundaries that are context-dependent, so that Avamar s client agents will be able to identify the exact same segments for any dataset, no matter where that dataset is stored in the enterprise. Avamar s segments average 24 KB in size and are then compressed to an average of just 12 KB. By analyzing the binary structure, Avamar s method works for all file types and sizes. For each 24 KB segment, Avamar generates a unique 20-byte ID, using the SHA-1 encryption algorithm. This unique ID is like a fingerprint for that segment. Avamar software then uses this unique ID to determine whether a data segment has been stored before. Files, directories, entire file systems, and even databases can be quickly and efficiently stored with a hierarchical map of these unique IDs. In summary, the benefits of Avamar s efficiency translate into: Reduction in daily network bandwidth and backup storage by up to 500x Daily full level backups across existing LAN/WAN bandwidth Up to 10x faster backup performance Reduction in total back-end disk backup storage by up to 50 percent Up to 85 percent reduction in total client CPU utilization. Avamar clients are run in low priority (or nice mode in UNIX), so as to not contend with resources. While Avamar clients typically use 15 percent more CPU than traditional backup agents during backup operations, Avamar reduces the window required for backup operations by up to 10x, thus reducing overall CPU utilization. Applied Technology 5
Immediate single-step recovery. Avamar stores all backups as virtual full images, which can be immediately recovered in a single step. There is no need to restore from full and incremental backups to reach the desired recovery point. Data Protection Advisor and Avamar Data collection from Avamar To gather data from EMC Avamar, DPA connects directly to the Avamar database. It connects to the mcdb database on the default port for Avamar, which is 5555. If these parameters were modified, change the Avamar Config and Avamar Job Monitor requests to override these DPA defaults to match the new Avamar parameter settings. When DPA connects to the database, it uses the viewuser account to log in to the database. If the Avamar installation was modified so that this user does not have permission to log in to the database, or the password for this user has been modified, change the user and password in the Default Avamar Credentials to reflect the username and password that should be used to connect to the database. The Collector must be installed on a host that is in the same time zone as the Avamar server. In DPA we have the standard Client and Group Configuration reports and Data Protection reports. In particular, the Data Change Ratio reports can help identify whether Avamar is being used efficiently and appropriately for the environment, and conversely, whether a non-avamar environment would be a good candidate for Avamar technology. This allows you to compare the amount of data being protected with the amount being backed up. Figure 1 shows a Control Panel Data Change Ratio Overview that aggregates three reports into a single view. Figure 1. Data Change Rate Overview Applied Technology 6
And reviewing reports by Client and Save Set level can help ascertain the rate of data change in the environment. Figure 2. Backup Job Change Ratios by Client Figure 3. Backup Job Change Ratios There are new features in Data Protection Advisor 5.0 that enhance the reporting available for Avamar environments. Data Protection Advisor provides many other reporting capabilities for Avamar environments that exist in previous versions. Improved deduplication reporting Data Protection Advisor includes reports that can be used to view the deduplication rates of clients being backed up by Avamar. The deduplication rate is calculated in the following way: Deduplication Rate = 100 ((Average Daily Change / Data Protected) * 100) Average Daily Change is calculated by looking at the backups that have taken place over the reporting period, and calculating the average amount of data transferred from a client to the Avamar Server on a daily Applied Technology 7
basis. The Data Protected number is the amount of data being protected on the client, and is taken from the last set of backups of that client, that is, it is not cumulative. A good starting point to review the deduplication rates of various clients is the Client De-Dupe Overview shown in Figure 4. This Control Panel consists of three reports: Backup Client De-Dupe Rate Distribution This report shows the number of clients with different deduplication rates. It is shown in an order that it is easy to see at a glance the most common deduplication rate you are getting in your environment, and how many clients might be getting poor deduplication rates, for example, < 10%. Top 10 Clients with Worst De-Dupe Rate This report displays the 10 clients with the worst deduplication rates in your environment. Top 10 Clients with Greatest Daily Change This report displays the 10 clients that on average are transferring the most data to Avamar Data Store on a daily basis. These clients are the ones that are likely to be causing capacity-related issues on Avamar Data Store. Figure 4. Client De-Dupe Overview A detailed report can be run from the menu that shows all clients configured on the Avamar Server, and displays the total amount of data protected, the average amount of data that has changed on a daily basis, and the deduplication rate. This is useful if you want to analyze more than just the worst 10 offenders detailed in the Control Panel. Applied Technology 8
Figure 5. Backup Client De-Dupe Ratios From the Client report, it is possible to drill down and view the deduplication ratios on individual jobs that have taken place on an Avamar client. If you have a client that has a particularly bad rate, then this report is useful to identify individual jobs that might have a high data change rate. Figure 6. Deduplication details by job Performance reports The standard Data Protection Advisor performance reports that report on the fastest and slowest clients have been modified so that for Avamar environments, the Throughput metric is derived by dividing the Total Amount of Data Protected against the Total Time, instead of the Total Amount of Data Transferred. Historically it was felt that performance metrics in EMC Data Protection Advisor for Avamar were too low, because the amount of data transferred in an Avamar backup is significantly smaller than a regular backup; so when performance is calculated as (data transferred)/(backup duration), the results were very low compared to other backups on non-deduplicating platforms. In order to fix this perception issue the new reports use the total amount of data protected as the measure for the throughput. The Backup Client Performance overview identifies the 10 clients with the fastest and slowest throughput in the environment, along with a distribution report that allows you to easily identify the range of throughputs that are being achieved by different numbers of clients. Applied Technology 9
Figure 7. Backup Client Performance overview Avamar Replication operations Data Protection Advisor now gathers information on Avamar Replication operations. Data Protection Advisor uses the term Clone instead of Replication, but the Clone Summary report displays the total number of Replication operations that have occurred and the total amount of data replicated. It also displays the amount of data that has been backed up over the same reporting period, and a Clone Ratio, which is defined as the percentage of data backed up that has been replicated. This number provides visibility into the deduplication ratio achieved when data is replicated from remote Avamar Data Stores to a centralized Data Store. Figure 8. Clone Summary ( Replication in Avamar) Detailed Replication reports provide information on the underlying replication operations that took place, providing details on which clients have been replicated successfully and which have not. Applied Technology 10
Figure 9. Replication job details Avamar Maintenance Jobs Data Protection Advisor has the ability to report on Avamar Maintenance Jobs, specifically Garbage Collection, HFS Check, and checkpoint maintenance. A maintenance summary report displays how many operations have ran, along with the success rate. The detailed job reports provide details on when the jobs ran, and how long they ran for. Figure 10. Maintenance Job Details The Maintenance Job Schedule report displays when Maintenance Jobs ran, relative to backup and replication operations. This makes it easy to identify when server-side Maintenance Jobs are running too long or running at the same time as backup or replication operations. Figure 11. Maintenance Job Schedule Applied Technology 11
Predictive job scheduling and reconciliation Data Protection Advisor gathers additional information about Avamar schedules, and can use this information to predict when backup jobs should run. This is useful if you are planning an outage in your environment in the future, and want to be able to determine which backups will be affected. The Job Forecast report shows jobs that should run between two times. Figure 12. Job Forecast The Job Forecast information is combined with information about backups that have really run in the Job Forecast versus Actual Summary report. This shows the total number of jobs that were expected to run, along with details of the actual number of jobs that really have run, and the number that are missing. This report is useful to identify backup jobs that should have run in your environment but that didn t for some reason, like a server outage. Figure 13. Job Forecast versus Actual summary In addition to the summary report, a detailed report provides details on all of the jobs, so that it is easy to identify those jobs that are missing. Applied Technology 12
Figure 14. Job Forecast versus Actual details Deduplication ROI Trend and Cost Savings reports The Deduplication ROI Trend report shows the return on investment for an Avamar installation over time. The ROI is calculated by looking at how much it would cost to fully protect the environment using a traditional backup application compared to the cost to fully protect the environment using Avamar. When the report is run, the user is prompted for two values: Cost/GB for backups. This is the current cost to back up a single gigabyte of data in your environment. Purchase cost. The total cost of the Avamar installation. This is the cost against which the savings are balanced to show overall ROI. Both values are in units of currency. For example, if the cost of the Avamar installation is $10,000 and the cost of carrying out backups is 1 cent per GB; enter 10,000 for Purchase cost and 0.01 for Cost/GB for backups. To obtain the best ROI information, the report should be run with a start time of when Avamar was first monitored and an end time of the current time. To view the Deduplication ROI Trend report, right-click on the Avamar server and select ROI from the drop-down menu, and then select Deduplication ROI Trend from the Navigation tree. Applied Technology 13
Figure 15. Deduplication ROI Trend The Deduplication Cost Savings report shows the cost savings of an Avamar installation for each machine being backed up. The cost savings are calculated by looking at how much it would cost to fully protect each client using a traditional backup application compared to the cost to fully protect each client using Avamar. When the report is run, the user is prompted for the value Cost/GB for backups. This is the current cost to back up a single gigabyte of data in your environment. The cost per GB is in units of your currency. For example, if the cost of carrying out backups is 1 cent per GB, enter 0.01 for Cost/GB for backups. To view the Deduplication Cost Savings report, right-click on the Avamar server and select ROI from the drop-down menu, and then select Deduplication Cost Savings from the Navigation tree. Figure 16. Deduplication Cost Savings Applied Technology 14
Conclusion The Avamar solution includes a variety of information and reports that customers find useful today. Data Protection Advisor extends the list of reports and analysis rules, adding new capabilities and report formats that customers have found useful. While DPA can be useful in an Avamar-only environment, its value increases when an environment has multiple backup solutions, multiple sites, or multiple business units. This paper does not cover all reports that are available within DPA, but it does highlight areas of interest when using DPA with EMC Avamar. References The following can provide additional information and can be found on Powerlink, EMC s passwordprotected customer- and partner-only extranet. EMC Data Protection Advisor Version 5.5 Architecture Overview EMC Data Protection Advisor Version 5.5 Compatibility Matrix EMC Data Protection Advisor Version 5.5 Installation Guide EMC Data Protection Advisor Version 5.5 Administration Guide EMC Data Protection Advisor Version 5.5 Reference Guide EMC Data Protection Advisor Version 5.5 Release Notes EMC Data Protection Advisor Version 5.5 User Guide Applied Technology 15