Best Practice Guide

Best Practice Guide Backup Exec from Symantec™ with DXi-Series

20020434-004 Rev A (BPG00006 V4)

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Best Practice Guide

Table of Contents DXi-Series Best Practices for Symantec Backup Exec.............................................. 1

Scope ....................................................................................................................................... 1 Installation Recommendations .................................................................................... 2

Virtual Tape Library Presentation: Fibre Channel/iSCSI .......................................................... 2 Robot/Media Changer Device Serialization and Recommendations ................................................. 2

Supported Hardware Compatibility List ...................................................................... 2 Virtual Tape Drive Device Description and Recommendation ........................................................... 3 CASO (Central Administration Server Option) vs. SSO (Shared Storage Option) ............................ 3 Fibre Channel SAN Zoning................................................................................................................. 3 Number of Concurrent Tape Drives in Use ........................................................................................ 4 Quantity and Capacity of Tapes ......................................................................................................... 5 Suggested Tape Cartridge Capacity .................................................................................................. 5 Tape Drive LUN Mapping ................................................................................................................... 6

Network Attached Storage Presentation: GbE......................................................................... 6 Replication Recommendations................................................................................................. 7

Integration Recommendations..................................................................................... 7 Backup Exec with DXi Series Configuration Guide .................................................................. 7 VTL Fibre Channel/iSCSI ......................................................................................................... 7

Performance Tuning ........................................................................................................................... 7 Eliminating Interference from the Host System.............................................................................................7 Configuration Recommendations:.................................................................................................................7

DXi as Network Attached Storage............................................................................................ 8 General Best Practices for DXi as a NAS target. .............................................................................. 8 Network-Attached Storage Settings and Tuning ................................................................................ 9

CIFS/NFS Recommended Mount Options ............................................................................... 9 Microsoft Windows CIFS Client Settings ............................................................................................ 9 Linux NFS Client Settings................................................................................................................. 10

Utilization Recommendations .................................................................................... 11 De-duplication Limitations ...................................................................................................... 11

Good Candidates for Data De-Duplication ....................................................................................... 11 Not So Good Candidates for Data De-Duplication ........................................................................... 11

Space Reclamation ................................................................................................................ 11 Recommended Handling of Expired Media............................................................................ 12

Trouble Shooting Backup Exec and DXi Solution.................................................... 15 DXi Advanced Features .............................................................................................. 15 Additional Information ................................................................................................ 15

The information provided in this document by Quantum is for customer convenience and is not warranted or sup-ported by Quantum. Quantum expects users to customize installation of third-party software for use to fulfill a cus-tomer driven requirement. However, Quantum is not responsible for the usability of third-party software after installation. This information is subject to change without notice.

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DXi-Series Best Practices for Symantec Backup Exec

Quantum Best Practices guide for DXi-Series (DXi2500-D, DXi3500, DXi6500, DXi7500 Express, and DXi7500 Enterprise) and Backup Exec by Symantec is provided to assist system administrators and backup administrators to get the most out of their investment. Quantum’s global field teams and devel-opment engineering teams contributed their expertise in creating these recommendations. The Quantum Best Practices Guides are routinely updated to include the latest enhancements, check with your Quan-tum sales team for the latest version.

Scope

The intended audience for this guide is our customers and field sales teams as guidance to enhance the installation, integration, and utilization of the Quantum DXi-Series. Specifically, this guide provides rec-ommendations and considerations impacting installation, integration, and utilization of the DXi-Series products for Backup Exec by Symantec environments.

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Installation Recommendations

Virtual Tape Library Presentation: Fibre Channel/iSCSI

Robot/Media Changer Device Serialization and Recommendations

Quantum is a leading manufacturer of automation devices and extends this knowledge and experience to the Virtual Tape Library (VTL) disk-based solutions. One of the key components to ensure that SAN-connected physical and virtual tape libraries are seen properly by backup servers is “serialization.” Seri-alization provides a unique identifier for each device in a physical or virtual tape library to automate de-vice association from multiple backup servers. These identifiers, returned by the VTL devices are separate from the “element address” that defines the position of devices in the library. The element ad-dress used by the library’s robot or medium changer to manage the tape drives.

Serialization allows the servers running the data protection application (the media servers) to coordinate tape drive configuration by aligning the device serial number with the device’s element address. This fea-ture enables Backup Exec device discovery to align these two addresses, reducing the potential for im-proper configuration. If the Device Configuration Manager does not serialize the devices listed, do not commit the changes, and check the VTL online state. The DXi™ VTL partition must be online for this to function properly.

The Quantum recommended device identification for each DXi system is the native mode (e.g., use the DXi3500 inquiry response string as the identification on a DXi3500, and use the DXi7500 inquiry re-sponse string on a DXi7500). This allows product identification for the service teams at both Symantec and Quantum. When using the native device mode, Windows environments will display the device in the device manager as an unknown media changer. This is normal and not an error or problem to Backup Exec. If the customer environment has requirements for a specific changer device for compatibility, the Quantum DXi products support emulation of many popular devices to meet those requirements.

Ensure that the latest drivers and firmware have been installed for the tape drive, robotic library, and for the HBA. Symantec drivers should be loaded for the tape drive for best performance. Symantec does not test performance or compatibility with Original Equipment Manufacturer (OEM) drivers, unless noted on the Hardware Compatibility List. Backup Exec tape drivers can be downloaded from the Symantec Support Web site at http://www.symantec.com/business/support/downloads.jsp?pid=15047 . Select the appropriate Backup Exec version number in the Product Version drop-down box, and select Driver as the File Type. To verify that the Symantec Drivers have been loaded for the tape drive, return to Device Manager in Windows and open the properties of the Tape Drive. Verify that the Driver Provider is Symantec.

Supported Hardware Compatibility List

If the device is presenting itself properly to the operating system, then it should be supplying the operating system with an inquiry string. In order for the device to work properly within Backup Exec, the inquiry string the device provides must match exactly with what is documented on the HCL: http://entsupport.symantec.com/carveout_PID_15047_view_CL.htm

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For detail on determining hardware compatibility refer to Backup Exec document: How to troubleshoot issues with a Robotic Library or Tape Drive in Backup Exec for Windows Servers. http://support.veritas.com/docs/255501

Virtual Tape Drive Device Description and Recommendation

Quantum DXi products support multiple tape drive emulations and allow user-definable capacities of tape cartridges to support the drive type. The drive type selection does not internally impose any throttling of the ingest rate. The host system uses tape device drivers to communicate with the virtual tape drives and the Backup Exec application. Refer to the Hardware Compatibility List for the supported drive emulation for your DXi model. http://entsupport.symantec.com/carveout_PID_15047_view_CL.htm

Quantum recommends using the Symantec Backup Exec Device Driver Installer – DDI to load the proper drivers for your devices. The Symantec DDI can be downloaded from http://www.symantec.com/business/support/downloads.jsp?pid=15047

CASO (Central Administration Server Option) vs. SSO (Shared Storage Option)

In Backup Exec 12.5 and later, CASO (Central Administration Server Option) includes SSO (Shared Stor-age Option) functions and is recommended in all cases except single BE server writing to one iSCSI DXi-series library in a small environment.

When working in an SSO environment, we recommend upgrading to CASO for enhanced management, usability and functionality.

When running a single standalone BE server, CASO (or SSO) option is needed to reach an FC target. CASO or SSO is not needed for a single standalone BE server to reach an iSCSI target.

When running multiple BE servers, CASO (or SSO) is required for FC or for iSCSI.

Fibre Channel SAN Zoning

There are several different approaches to zone a Fibre Channel SAN for a variety of different SAN ob-jects. The best practice for zoning a single backup server or a group of backup servers to connect to a single shared backup target could become quite complex. If the backup server consists of 2 or more Fi-bre Channel nodes, a single object such as a tape drive could possibly be presented to the backup server multiple times. The Fibre Channel Host Bus Adaptor (HBA) is normally configured as a SAN initiator be-cause the request for a dialog or transaction is normally initiated by the backup server via the FC HBA. The object that receives the signal from the SAN Backup initiator is called the SAN Backup Target or SAN Target.

The implementation of a SAN zone that dictates that the SAN Initiator Node or port on the HBA is as-signed to a zone that speaks to only 1 target Node or port is called a Single Initiator Zoning method.

By implementing Single Initiator Zoning, an administrator will have a much greater flexibility (and confi-dence) with adds, moves, and changes as each Initiator is separately zoned and changes won't affect other Initiator/Target combos in the same fabric. The following is an illustration of a Single Initiator Zoning method across multiple servers that contain 2 FC Nodes / ports.

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Notice that a single FC Node could reside in multiple zones. This is due to the fact that it has multiple targets to contact.

Number of Concurrent Tape Drives in Use

Each DXi model has a maximum number of virtual tape drives that can be configured. Each DXi model has a maximum aggregate throughput rate that will be divided relatively equally between the virtual tape drives in use. That does not prohibit a single tape drive from utilizing all available bandwidth. The media server typically determines individual tape drive performance.

It is not a good idea to configure the maximum number of virtual tape drives and to perform I/O through all of them concurrently. Better performance can be achieved by using a subset of those virtual tape drives at the same time. Quantum expects the customer configuration to distribute those virtual tape drives among multiple media servers to simplify initial installation by providing dedicated resources to each me-dia server. Quantum recommends that backups be staggered such that only a subset of drives are in use at one time. During a backup, the data transfer rate is primarily controlled by the media server because the DXi system does not restrict the ingest data rate. This creates the opportunity for one or more media servers to burst data at a higher rate leaving the remaining virtual tape drives less bandwidth. Conversely, it supports the coexistence of fast data streams with slow streams for the maximum utilization of the available bandwidth.

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Note: Increasing the number of concurrently active virtual tape drives does not increase the aggregate DXi bandwidth and could result in a failed backup job due to a timeout from a bandwidth-starved opera-tion.

The recommended maximum number of concurrently active virtual tape drives for the respective system bandwidth is listed in the table below.

DXi Model Maximum

Virtual Tape Drives

Maximum Aggregate Bandwidth

Recommended Maximum Number of Concurrently-Active Virtual Tape Drives

DXi3500 32 290GB/Hr or 80MB/sec Up to 8 concurrently-active virtual tape drives * DXi7500 Express 80 1.28TB/Hr or 355 MB/sec Up to 17 concurrently-active virtual tape drives ** DXi7500 Enterprise 160 4TB/Hr or 1,111MB/sec Up to 55 concurrently-active virtual tape drives **

* Based on a user wanting no less than 10MB/sec per virtual tape drive. ** Based on a user wanting no less than20 MB/sec per virtual tape drive.

Note: iSCSI with a lower maximum transfer rate should stay below the SCSI2 limit of eight LUNs maxi-mum and concurrent drives should be set to four based on a GbE interface connection and ½ the 2GB Fibre Channel suggested limits. It is also a good practice to keep the iSCSI traffic separate from the pro-duction system network to prevent contention with end users for bandwidth. Quantum iSCSI devices for Solaris initiator require the Qlogic TOE HBA.

Quantity and Capacity of Tapes

Quantum suggests not oversubscribing the device capacity when initially creating tape cartridges and recommends that the DXi installation team show the customer how to create additional virtual tape car-tridges to be added as needed. This recommendation is to assist the user with managing the available space on the DXi device. The initial number of tapes to create should be based on the sizing exercise performed by the Quantum System Engineer.

The DXi system can send alerts when the unit detects the user-selectable capacity point. Quantum rec-ommends this feature be configured and utilized to alert the user before unknowingly arriving at a low space condition. When the backup environment requires additional virtual tapes cartridges and there is sufficient space available, the user can add additional virtual tape cartridges to a partition and run an in-ventory to update the Backup Exec database.

Suggested Tape Cartridge Capacity

Space on tape cartridges cannot be reused until after all backup data on that cartridge has expired. The greater the capacity of a cartridge, the longer it will typically take for all data on that cartridge to expire. Expired data continues to take up space on the virtual tape cartridge as well as in the DXi until that car-tridge is overwritten, relabeled, or erased. A lesser tape cartridge capacity is more desirable so that tapes are returned the Backup Exec scratch pool for reuse and overwritten sooner.

There is virtually no relationship between the configured capacity of a virtual tape cartridge and the tape drive emulation that has been configured for the partition: ■ Any backup/restore operation will span the number of tapes required, ignoring the configured ca-

pacity. ■ Any vaulting/duplicating operation performed by the backup application will ignore the virtual ca-

pacity when writing to another cartridge, whether virtual or physical. ■ DXi 3500 and DXi 5500 allow you to specify a maximum capacity up to the available capacity of

the DXi; the minimum is 5GB. Be aware that capacity utilization for these models is tracked in UNCOMPRESSED GB, al-

though the data is stored compressed. That is, 100GB of data that is 2:1 compressible will re-port that it occupies 100GB of virtual tape cartridge space. If it is new unique data, it will be

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compressed 2:1 before being written to the de-duplication data pool. If it is not new unique da-ta, then a pointer will be substituted for that data and the pointer will point to the original copy of that data in the de-duplication pool.

■ DXi7500 will limit you to the maximum capacity permitted by the tape drive emulation; the mini-mum is 5GB.

Be aware that capacity utilization for DXi7500 is tracked in COMPRESSED GB and the data is stored compressed. That is, 100GB of data that is 2:1 compressible will report that it occupies 50GB of virtual tape cartridge space.

Quantum’s general guidance is to specify a smaller virtual tape cartridge capacity such as 50-100GB, for the reasons mentioned above.

For Backup Exec recommendations on media management, refer to “The basics of Advanced Device and Media Management for Backup Exec for Windows Servers.” http://seer.entsupport.symantec.com/docs/192265.htm

Tape Drive LUN Mapping

Quantum recommends mapping the device starting with LUN 0 on each port and not skipping any LUNs.

Quantum recommends a best practice of zoning the VTL devices and the Backup Exec media servers to prevent other servers from taking control of the VTL resources. Additionally, we recommended using the HBA driver to bind the devices to a specific address. This helps keep devices in the same order after a reboot. Quantum also recommends setting the WWNN = WWPN for DXi3500 and DXi7500 systems. This allows for binding on the HBA to use either WWNN or WWPN.

Quantum DXi-Series VTL devices support reserve and release to accommodate sharing drives. The op-tion allows devices to be shared between Backup Exec media servers. The advantage is having a pool of drives available to each media server. Other SAN architectures assign drives to each media server and eliminate the shared function. For both conditions, it is a good practice to keep the Backup Exec media server separate from the production server to eliminate downtime from maintenance. This requires the media servers to have fast network connection to the source data.

Network Attached Storage Presentation: GbE

The Quantum Network-Attached Storage (NAS) appliance is intended to act as a target for backup appli-cations. This includes Network-Attached Storage or shares. Backup Exec can use the NAS shares as a Backup-to-Disk Target.

Note: The NAS shares created on the DXi system are not recommended for general-purpose storage.

Quantum DXi systems support both CiFS (Windows-based) and NFS shares. Each system can support multiple NAS shares with a maximum of 128 shares. Quantum recommends users only creating the re-quired number of shares for each media server. DXi systems can support concurrent NFS and CiFS shares and can support iSCSI and Fibre Channel VTLs concurrently with those NFS and CiFS shares.

When using NAS shares on the DXi systems, Quantum recommends creating at least one share for each media server to use. Media servers should not share the NAS shares during normal backup operations.

Root access to a NFS share is not allowed and the access rights will be changed to “nfsnobody” as a security precaution. This does not impact the access to the share from the backup application.

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Replication Recommendations

For first-time replication setup, it is important to manually replicate the name space once the target sys-tem is configured and is online. This facilitates the first replication following the first backup to that share/partition. The replication is only available to VTL and NAS shares with de-duplication enabled. The DXi supports 128-bit AES encryption for replication. Data is only encrypted while in transit between repli-cation source and replication target. Data is unencrypted upon arrival at the replication target. Encryption may affect replication performance. It should be disabled if the customer’s WAN is already secured.

Please refer to the Quantum DXi-Series Best Practices for Data Replication (Document 20020430-xxx).

Integration Recommendations

Backup Exec with DXi Series Configuration Guide

The Backup Exec with DXi Series Configuration Guide contains additions additional information about configuring solutions with Backup Exec (see the Backup Exec with DXi-Series Configuration Guide PN 20020435-xxx)

VTL Fibre Channel/iSCSI

Performance Tuning

Combining our in-house testing, partner information sharing and customer feedback, we have found en-hanced performance for Backup Exec environments by using the following tuning parameters:

Eliminating Interference from the Host System

According to Microsoft, “a conflict in Windows Server 2003 causes a Test Unit Ready (TUR) request issue on SCSI-attached and fiber-attached devices. When this issue occurs, an overflow of TUR requests causes the storage unit not to respond or to respond slowly to SCSI commands. In a SAN environment, any Windows Server 2003-based computer that is zoned to detect the Tape Backup Unit hardware can send TUR requests.” The cause and workaround are documented in the Microsoft knowledge base article number 842411. Microsoft support link: (http://support.microsoft.com/kb/842411/en-us).

Configuration Recommendations:

• Set VTL Emulation to the Native DXi String, or Quantum Scalar i2000.

• Emulate drive sign-on string as per the Backup Exec HCL o DXi7500: HP LTO4 or HP LTO3. o DXi3500: HP LTO4 or HP LTO3.

• Set up no more than 1-2 drives per 3.xGHz CPU core. Server should have 2GB RAM plus 1GB per drive. If performance per data stream seems low, disable CPU hyper-threading on master or media server and verify whether this improves your speed per stream; it may be necessary to keep Hyperthreading disabled for best throughput per stream.

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• Use only standard ANSI characters for the computer name of the computer on which you want to install Backup Exec. You may receive errors if you install Backup Exec on a computer with a name that uses non-standard characters.

• Disable the operating system's Removable Storage Manager (RSM) service. (This is disabled by default in Win 2003/2008.)

• Disable Microsoft Volume Shadow Copy service.

• Disable Microsoft Advanced Open File System service.

• Set each tape drive’s device settings in BE Device tab - Properties:

o block size 1024KB on LTO4, or 512KB on LTO3

o Buffer size 1024KB

o Buffers 30

o High water mark 15

o Stop & restart BE device services after making these changes on each Media Server.

Consult any of the following resources on the Help menu if you have questions or difficulties:

• Use the Administrator's Guide for comprehensive information about Backup Exec.

• Use the Backup Exec Help for searchable, topic-based documentation.

• Use the Getting Started screen to help you work through the most common configuration steps.

• Use the Backup Exec Assistant for access to wizards, documentation, and technical support.

DXi as Network Attached Storage

General Best Practices for DXi as a NAS target.

• In Windows Active Directory environments, the share acts as the target for the NetBackup. The share is not intended as primary storage or drag-and-drop storage. A best practice is to create a new account and workgroup as opposed to joining the domain to limit the access and prevent ac-cidental file deletion by another user. Quantum recommends users not reconfigure or delete NAS shares while data is being written. There is no mechanism to detect the I/O and provide a warning to the user.

• Use a dedicated network for backup data or use QoS features that guarantee network bandwidth. Another option would be to use virtual networks (VLANs) to segregate backup from production network traffic.

• Configure network interface cards (NICs) in servers, clients and set routers to full duplex.

• Use only CAT 5e or CAT 6 cables (1Gb/s rated cables).

• If using a DNS server, verify the DNS server configuration settings are correct using nslookup on the host name as well as the IP address

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• It is also a good idea to add the HOST NAME and IP Address to the host file

• Use multiple DXi ports when connecting to the network. The more DXi Ports used the better the performance capability will be across the ports.

• For redundancy, connect a least two DXi ports to an Ethernet switch.

• Set each switch port used by the DXi to auto-negotiate/auto-sensing. The DXi network interface cards are preset to auto/auto and cannot be changed.

Network-Attached Storage Settings and Tuning

Quantum recommends running Backup Exec 12.5 SP2 or later to take advantage of specific NAS & NDMP enhancements in the 12.5 SP2 release.

When using DXi as NAS for a Backup-to-Disk target, consider the following when you create a backup-to-disk folder:

• Set the maximum size for backup-to-disk files to an appropriate size. If you create small but nu-merous files, performance may slow since the computer must still process each file. However, if you create large files, file system limitations can cause memory allocation problems or network issues. These issues can be a problem if you store files across a network.

• Specify fewer backup sets in a backup-to-disk file to allow Backup Exec to reclaim disk space faster. Fewer backup sets may allow the overwrite protection period to expire sooner.

• Enable the option Allocate the maximum size for backup-to-disk files to reduce disk fragmenta-tion. To ensure that backup data fills each backup-to-disk file to capacity, increase the append period of the media set that you associate with the backup-to-disk files. The backup data's over-write protection period may also increase because the overwrite protection period starts at the end of the last append job.

Note: Backup performance may be affected when you enable the option Allocate the maximum size for backup-to-disk files. To find what works best for your environment, enable this option for a job. Then, compare the performance with a job that does not allocate the maximum size for backup-to-disk files.

Experiment with the options for buffered reads and buffered writes. Enabling these options may increase backup performance.

CIFS/NFS Recommended Mount Options

The following settings are recommended to optimize NAS Performance.

Microsoft Windows CIFS Client Settings

Step #

Configuration and Settings

Microsoft provides comprehensive guidelines for configuration and tuning for networks and storage in the documents referenced below.

Windows XP

http://support.microsoft.com/kb/314053/

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Windows 2003

http://download.microsoft.com/download/2/8/0/2800a518-7ac6-4aac-bd85-74d2c52e1ec6/tuning.doc

Windows 2008

http://download.microsoft.com/download/b/b/5/bb50037f-e4ae-40d1-a898-7cdfcf0ee9d8/WS08_STEP_BY_STEP_GUIDE/WS08PerformanceTuningGuide_En.docx

http://download.microsoft.com/download/9/c/5/9c5b2167-8017-4bae-9fde-d599bac8184a/Perf-tun-srv.docx

Windows Vista

http://download.microsoft.com/download/c/2/6/c26893a6-46c7-4b5c-b287-830216597340/TCPIP_Reg.doc

Linux NFS Client Settings

Step # Configuration and Settings

1 Change socket buffer settings to 4M default. Append these lines to /etc/sysctl.conf

net.ipv4.tcp_rmem = 4194304 4194304 4194304

net.ipv4.tcp_wmem = 4194304 4194304 4194304 net.ipv4.tcp_mem = 10485760 10485760 10485760

net.core.netdev_max_backlog = 30000

Run the command sysctl –p for the newly added configuration to take effect. Verify the configu-ration by running sysctl net.ipv4.tcp_rmem, it should show 4194304 4194304 4194304.

Note: Set the socket buffers before doing mounts from clients. If they are already mounted, cli-ents need to unmount and remount for the settings to take place. The unmount and remount may be done after the client is fully configured.

2 OPTIONAL. If your client has multiple NICs bonding can be beneficial.

Create Link aggregation group with LACP

And add bonded round robin policy by adding this line in /etc/modprobe.conf:

options bonding mode=6 miimon=500

[NOTE: During this testing, in lieu of LACP, Layer3+4 xmit_hash policy was also successfully used to reduce TCP retransmissions.

In the /etc/modprobe.conf, add the line

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options bonding mode=2 xmit_hash_policy=layer3+4 miimon=500

NOTE: this step needs a reboot.

3 Mount with rsize/wsize set to 1M. This testing almost always had at least 4 mounts to the DXI 7500. Each mount was to one unique IP address.

mount –o vers=3,tcp,rsize=1048576,wsize=1048576 …

NOTE: The older versions of Linux (pre-2.6.16) only support maximum of 32K rsize/wsizes that are not optimal. 2.6.18 and recent versions showed better performance.

4 Verify the mount options by running the command cat /proc/mounts

Utilization Recommendations

De-duplication Limitations

De-duplication results can be negatively impacted by compression and encryption.

Compression and/or encryption of data before it reaches the DXi may also cause a similar reduction in de-duplication results and can also cause much higher CPU loading on the media server.

Quantum recommends that inline compression by the backup application, and inline encryption by either the backup application or an inline appliance be disabled in order to achieve maximum de-duplication of the data.

Good Candidates for Data De-Duplication

VMware, large databases (note exceptions below), PowerPoint presentations, Word documents, Excel spreadsheets, SQL, Oracle (note exceptions below), Exchange database, source code

Not So Good Candidates for Data De-Duplication

In-line compressed data, SQL with LiteSpeed (in-line compression), Oracle with multi-channel RMAN (in-line multiplex), and in-line encrypted data, compressed video, compressed audio, compressed jpg.

For long-term archiving, we recommend vaulting the data to a physical tape device.

Space Reclamation

Space management involves two processes: data reconciliation and data reclamation. Data reconciliation is used to create a list of what can be removed. It runs automatically every twelve hours at noon and mid-night, unless data reclamation is running. Data reclamation is the process of deleting the data on the data reconciliation list. It can be scheduled or run manually. There is significant overhead associated with this process and, therefore, it should not be run during periods of high appliance use. Replication, reclama-tion, and backup stream ingest all consume system resources and, therefore, should not all be done at the same time.

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Quantum recommends scheduling daily reconciliation and reclamation to manage the available space. The scheduled time should be configured to start the data reclamation process after the daily backups are complete. The default schedule is weekly and the default time for the data reclamation is set to 12:00AM Sunday. These parameters are user configurable and should be configured for the customer backup window.

Recommended Handling of Expired Media

When a tape is expired by Backup Exec, there is no direct communication of the event to the DXi-series. The result is a tape may be displayed as empty or SCRATCH to the Backup Exec graphical Interface, but will show the same tape on the DXi-series GUI as containing data. This indicates the data on the expired tape is still using space on the DXi-Series library.

Use the Backup Exec media management option to overwrite recyclable media before you overwrite scratch media. This media management option is named Overwrite recyclable media contained in the targeted media set before overwriting scratch media. You can find this option under Tools > Options > Media Management.

Create media sets with append and overwrite protection periods that just accommodate your needs. When the COMBINED append and overwrite-protection periods expire, the media are recyclable and Backup Exec has access to overwritable media. ALL 3 STEPS listed below must be followed, to limit a given media set to using the amount of DXi space allocated in a DXi-sizing exercise.

1. Change media retention settings to use recyclable media before scratch: BE Administration Console (main BE GUI) - Tools – Options – Media Management default = scratch media if no appendable media is available CHANGE TO = use recyclable media in the set before creating a new scratch piece of media

2. Change media set append period to 2 weeks, or to as short a time as is workable based on your DXi sizing exercise. On each media set: Right-click - properties – append period default = infinite allow append CHANGE TO recommended = 2 weeks

3. Change media set Overwrite-Protection period to 10 weeks, or to as short a time as is worka-ble based on your DXi sizing exercise. On each media set: Right-click - properties – overwrite protection period default = infinite CHANGE TO recommended = 10 weeks

Overwrite or re-label expired media as needed periodically, to keep the media family at a manageable size so that Backup Exec can rebuild the catalog if necessary. You can use a media rotation strategy so that media is periodically overwritten, or select the option Overwrite media when you run a full backup.

Remove excess media from a media set and return to the Scratch pool. If the media set grows and needs more virtual cartridges, it will get them from the scratch pool again, but in the meantime you want to keep Backup Exec in the cycle of re-using its intended media set most efficiently.

Do not use the default overwrite protection period of infinite for all media: • Backup data may consume tape and disk capacity quickly. • Media does not become recyclable automatically. You must specify when to overwrite each me-

dia.

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Backup Exec media types, options, and behaviors described:

Scratch media: Media that can be overwritten by any backup operation and is in the Scratch Media set. Scratch media will be displayed in blue under the Scratch Media set. It can be new media, blank media, erased media, or media moved from another media set. When Scratch media is used for a backup opera-tion, Backup Exec automatically moves the media to the User Media set that was targeted during the backup operation. The media color will then change from blue to black, and the media will inherit the overwrite protection period and append periods for that User Media set.

User Media sets: User Media sets contain all the allocated media that are assigned to media sets. Allocated media: Media that is part of a User Media set and has not had its overwrite protection period expire. The media may also be available for append operations if the append period for the media has not expired. The media will be displayed in black under the User Media set. Once the overwrite protection period expires, the Allocated media becomes Recyclable media, is displayed in blue, and will remain in the User Media set. Recyclable media: Allocated media that is part of a User Media set and has had its overwrite protection period expire. The media is available for overwrite operations or append operations (append operations are only possible if the append period still allows the media to be appended to). The media will be dis-played in blue under the User Media set.

Overwrite protection period: The amount of time specified in hours, days, weeks, or years to keep a piece of media from being overwritten. Change the overwrite protection period from the default of Infinite - Don't Allow Overwrite, to the shortest acceptable period; Quantum recommends a period that matches the number of weeks specified during your DXi sizing-exercise, MINUS the number of days or weeks specified in the Append Period. For example: If the overwrite protection period is set to 10 weeks and the Append Period is set to 2 weeks, the media will be protected from being overwritten for 12 weeks. After these 12 weeks are over, the media becomes Recyclable and can be overwritten. The overwrite protec-tion period is measured from the time when the last overwrite or append operation ended.

Append Period: The amount of time specified in hours, days, weeks, or years that data may be added (appended) to a media. Change the append period from the default of Infinite - Allow Append, to the shortest acceptable period; Quantum recommends 2 weeks. If the append period is set to two weeks for example, the media can be appended to for the next two weeks. After these two weeks are over, the me-dia cannot be appended to. The append period is measured from the time the media was first allocated to the media set or overwritten.

How does Backup Exec choose media to overwrite?

Backup Exec 12.x allows the user to choose where Backup Exec should look for media to overwrite. The two new options are: 1. Overwrite scratch media before overwriting recyclable media contained in the targeted media set. Un- select this option. Backup Exec will overwrite scratch media first before overwriting recyclable me-dia when an overwrite job occurs. If there is no scratch media in any of the storage devices, Backup Exec overwrites recyclable media in the targeted media set. If there is no recyclable media found, Backup Exec automatically searches for other media to overwrite. Which media is overwritten depends on the level of overwrite protection (Full, Partial, or None) that has been set. If this option is selected, more media may be required for the same number of jobs as compared to when it has been chosen to overwrite recyclable media first. Because this option affects the order in which Backup Exec overwrites media, choosing to overwrite scratch media first may allow the recyclable media to be preserved longer for possible recovery. 2. Overwrite recyclable media contained in the targeted media set before overwriting scratch media. SELECT THIS OPTION. Backup Exec will overwrite recyclable media in the targeted media set before overwriting scratch media when an overwrite job occurs. If there is no recyclable media in any of the stor-age devices, Backup Exec overwrites scratch media. If no recyclable or scratch media are found, Backup Exec automatically searches for media to overwrite. Which media is overwritten depends on the level of overwrite protection that has been set (Full, Partial, or None). If it has been chosen to overwrite recyclable

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media in the targeted media set first, the same media will be reused more frequently as compared to when it has been chosen to overwrite scratch media first.

When performing an overwrite backup operation once Backup Exec is set to use recyclable media before scratch media, Backup Exec follows these steps to find media available for overwrite:

1. Backup Exec first searches for recyclable media in the User Media set targeted in the backup opera-tion.

2. If recyclable media in the targeted User Media set is not available, Backup Exec next searches for Scratch media that can be overwritten.

3. If scratch media is not available for overwrite operations, Backup Exec next searches for recyclable media in all other User Media sets for media that can be overwritten.

4. If recyclable media is not available for overwrite operations and Backup Exec Media overwrite protec-tion has been configured as Full, Backup Exec will prompt for a scratch media.

5. If recyclable media is not available for overwrite operations and Backup Exec Media overwrite protec-tion has been configured as Partial or None, Backup Exec will search for media that can be overwritten in the Imported Media set.

6. If Imported media is not available for overwrite and Backup Exec Media overwrite protection has been configured as Partial, Backup Exec will prompt for a Scratch media.

7. If Imported media is not available for overwrite and Backup Exec Media overwrite protection has been configured as None, Backup Exec will search for Allocated media (media in User media sets that is not recyclable).

8. If Backup Exec still cannot find media, Backup Exec will prompt the user for scratch media.

How does Backup Exec choose media to append?

Backup Exec now allows the user to choose what Backup Exec should do when performing an append job but no appendable media is present. This can be done on a per job basis. The two new options are:

1. Append to media, overwrite if no appendable media is available Backup Exec will append the backup to the media set listed in the Destination | Media Set field in this dia-log box. The backup set is appended if an appendable media is available in the selected media set; if not, an overwritable media is used and added to the media set. Caution: If an append job fills a media, the job continues on another piece of overwritable media. Depend-ing on your configuration, overwritable media is selected from recyclable or scratch media. If the media in the drive is not overwritable, a message is displayed, which requests for a scratch media to be inserted.

2. Append to media, never overwrite Backup Exec will append the backup to the media set listed in the Destination | Media Set field in this dia-log box. The backup set is appended if an appendable media is available in the selected media set; if not, the job is terminated.

When performing an append backup operation and the backup job is set to append to media, overwrite if no appendable media is available, Backup Exec follows these steps to find available media:

1. Backup Exec first searches for appendable media in the User Media set targeted in the backup opera-tion.

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2. If no appendable media can be found and the backup job is configured to Append to media, overwrite if no appendable media is available, Backup Exec changes the backup operation from append to overwrite and continues with the search for media.

3. Refer to items 1 to 8 of the overwrite backup description above.

When performing an append backup operation and the backup job is set to append to media, never overwrite, Backup Exec follows these steps to find available media:

1. Backup Exec first searches for appendable media in the User Media set targeted in the backup opera-tion.

2. If no appendable media can be found, the backup job is terminated.

Caution: It is strongly recommended that careful consideration should be made before setting the media overwrite protection level to None. When the overwrite protection level is set to None, all media is subject to being overwritten regardless of media set, overwrite protection period, append period, or any other property.

For Backup Exec discussion on media management, refer to “The basics of Advanced Device and Media Management for Backup Exec for Windows Servers.” http://seer.entsupport.symantec.com/docs/192265.htm

Trouble Shooting Backup Exec and DXi Solution

For a comprehensive guide to troubleshooting the Backup Exec environment, refer to:

How to troubleshoot issues with a Robotic Library or Tape Drive in Backup Exec for Windows Servers.

http://support.veritas.com/docs/255501

DXi Advanced Features DXi provides the ability to create copy virtual tapes to physical tapes for offsite vaulting. The following guide details how to configure Shadow Tape Creation with DXi and Backup Exec:

• DXi7500 Shadow Tape Creation Quick Start Guide (PN 6-66544-xxx)

Additional Information ■ Quantum web site: http://www.quantum.com ■ Microsoft web site: http://www.microsoft.com ■ Symantec web site: http://www.symantec.com/business/support/overview.jsp?pid=15047 ■ Guardian web site:

http://www.quantum.com/ServiceandSupport/Services/GuardianInformation/index.aspx ■ StorageCare Vision web site:

http://www.quantum.com/Products/Software/Storagecarevision/Index.aspx ■ Quantum Service web site: http://www.quantum.com/ServiceandSupport/Index.aspx

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