1. Backups George Hewitt BCS Teesside - 8 th Feb 2012

2. Where we’re going Why backup? Key ideas Backup/restore methods Example architecture Backup media

3. Context Survey of European firms: –54% had lost data or suffered systems downtime in past 12 months –74% were ‘not very confident’ they could fully restore their networks –Most common cause of data loss/downtime was hardware failure http://www.bbc.co.uk/news/business-15866885

4. Why backup? Mitigate risk of downtime –Hardware failure, natural disasters etc Mitigate risk of data loss –User/software error (including malice!) or corruption How expensive is downtime/data loss to you? A backup infrastructure will form part (or all) of a DR/BC architecture

5. Key Metrics Recovery Time Objective (desired) Recovery Time Capability (current) Recovery Point Objective Retention period (D/W/M) An idea of what you consider unacceptable downtime will guide you towards what sort of DR/BC architecture you need

6. What are not backups? RAID Clustering / NLB / other HA VM snapshots System restore Outlook PST on local machine Shadow copies?

7. Types of backup Full backup Incremental – changes since last backup Differential – changes since last full Synthetic full Continuous data protection SunMonTuesWedsThursFriSat

8. Types of Restore Granular Restore Technology –Aka File/Object Level Restore Bare-metal restore

9. Traditional backup architecture

10. Semi-virtualised architecture Over LAN

11. Traditional Backups Benefits –Single management interface –Direct control over backup selection lists Downsides –No reduced costs (backup agent on each VM) –Slow to backup (all traffic over LAN) –Slow to restore (especially baremetal!)

12. Or…. Over LAN

13. VM Snapshots

14. VM Disk-level backup LAN or Storage Network VM Host & StorageBackup staging storage LAN LAN-free Over storage (FC / iSCSI etc) eg VCB / vStorage API BackupExec VCB, Quest vRanger, Veeam

15. Interesting Extras! Changed Block Tracking –Improve incremental VMware backups –Backup software requests changed blocks since last backup –eg. 500GB server taking 2hrs, now only 40mins! Active Block Mapping –Only blocks in use by the VM are backed up –Software interrogates filesystem (eg NTFS) –eg. Deleted data is ignored

16. VM Quiescing To enable application-consistent backups (eg for SQL, Exchange) –Tells the OS/Application to ‘get ready’ for a backup Off = crash consistent backup! However – may require additional scripting depending on application

17. File-level Restore of VM

18. Restore Demo

19. Example Architecture Medium-size business – 200 users. –10 servers –Active Directory, Exchange, SQL, File & Print, line of business application –Single VM host with local storage (all servers) –BackupExec installed on VM but selection lists have been restricted to data only –Backups completed to tape –RTO is 1hr. Current RTC is 2 days

20. Example Architecture Provision new physical backup server with disk staging Use appropriate software to perform VM-level backups for most servers BackupExec to duplicate VM backups to tape Use BackupExec agents for Exchange Mailboxes and SQL server Invest in HA SAN or host replication

21. A note on SQL Precise method used to backup depends on your RTO/RPO (and size/number of databases) SQL Agent Backup Jobs can be an option (backup to flat-file) for small number of databases

22. Backup Media

23. Disk-to-disk NAS / Disk shelves Advantages –fast! Disadvantages –expensive (consider retention period) –physical protection (onsite/offsite?)

24. Disk-to-tape eg LTO Ultrium 3/4/5 –LTO5 native capacity 1.5TB (2:1 compression ‘possible’) Advantages –High-capacity, long life (15-30 years archival) Disadvantages –slow (sequential access)

25. Disk-to-cloud? ie. Backup to a 3 rd party over the Internet Costs can be attractive But… consider –Size of dataset (and/or, speed of link) –Replication vs retention –Speed of recovery (and/or, speed of link!) –Bare metal restores

26. Disk-to-disk-to-tape Disk to Disk (backup) –Fast – during backup window –Might keep <= 2wks on disk for quick restores Disk to tape (duplication) –Slow – during working hours –Tapes can then be exported and safely archived offsite

27. Scaling it up.. BackupExec – does not scale as well Enterprise solutions –Eg Netbackup / CommVault –Better multi-platform support –Better management of large server numbers –Additional features (archiving, de-duplication) –Integration with other products (eg vRanger) still possible

28. Other things to consider… Large static datasets –candidate for archiving first? Storage of backup data –Retention periods –Offsite –‘Critical spares’

29. Other things to consider… Remember – a backup is only as good as the restore Backups may sit alongside other processes such as replication Have a DR strategy and test it!

30. Q&A