1 / 30


Backups. George Hewitt BCS Teesside - 8 th Feb 2012. Where we’re going. Why backup? Key ideas Backup/restore methods Example architecture Backup media. Context. Survey of European firms: 54% had lost data or suffered systems downtime in past 12 months

Télécharger la présentation


An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.


Presentation Transcript

  1. Backups George Hewitt BCS Teesside - 8th 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

  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 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 VM Host & Storage Backup staging storage LAN or Storage Network • LAN • LAN-free • Over storage (FC / iSCSIetc) • egVCB / vStorageAPI • 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 3rd 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 • EgNetbackup / CommVault • Better multi-platform support • Better management of large server numbers • Additional features (archiving, de-duplication) • Integration with other products (egvRanger) 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

More Related