Common Backup & DR Strategies - Comparison Table

The below table is designed to serve as a quick reference to compare common backup and disaster recovery strategies. It is certainly not an exhaustive list, but covers the majority of backup and disaster recovery solutions I have encountered while speaking with resellers in Australia - if you have any comments or can suggest some alternative solutions that should be included in this table, please let me know.

	Protects Against				Features / Cost
Common Backup Strategies	Hardware Failure?	Human Error (accidental deletion etc.)	Virus / hacker attack?	Fire, theft, natural disaster?	File Recovery time	Full Recovery time	Recovery Point	Cost
File Backup to Removable media (tape, external HDD, RDX, Flash drive) taken offsite	Yes	Yes	Yes. Data is kept offline	Yes	Slow. Media must be brought back onsite to recover files	Slow Even if replacement hardware is available, Server will need to be rebuilt, and media brought back to site before files can be restored	Depends on last backup job, Typically  24hours for  offsite nightly backup	Affordable. Consists of upfront hardware cost, cost of labour to take media offsite and potentially store
File Backup to NAS or SAN Onsite	Yes	Yes.	No. Data is online and on the same network so can be attacked by virus or hacker.	No	Fast Files are easily accessed as data is online.	Slow Systems need to be restored before files can be brought back	Depends on last backup job but tend to be scheduled to run more frequently than offsite nightly backups	Affordable, Upfront hardware cost for disk array
File Backup to the ‘cloud’	Yes	Yes	Yes / No Data is online, but on a different network, so chances of complete data loss are small, but still feasible (e.g. lost passwords)	Yes	Slow / Fast Depends on the size of the file and bandwidth, but for small files recovery should be quick	Slow Systems need to be restored, and data copied or physically brought back to site before files can be brought back	Depends on last backup job, Typically 24hours for  offsite nightly backup, but easy to schedule to run more frequently	Affordable, low or no upfront cost, but ongoing subscription and bandwidth cost can ultimately be more expensive than two options above
File level backup to NAS or SAN Onsite, then to Removable media (tape, external HDD, RDX, Flash drive) taken offsite. (D2D2T)	Yes	Yes	Yes	Yes	Fast Files are easily accessed as data is available on LAN	Slow Systems need to be restored before files can be brought back	Depends on last backup job	Mid-range. Consists of upfront hardware cost, cost of labour to take media offsite and potentially store
Image level Backup to Removable media (tape, external HDD, RDX, Flash drive) taken offsite	Yes	Yes	Yes	Yes	Slow Media must be brought back onsite, and depending on software may need to be mounted to recover individual files	Slow / medium If replacement hardware is available, once media is onsite, image level restore should save time as OS & apps do not need to be installed prior to recovery	Depends on last backup job, Typically 24hours for  offsite nightly backup	Mid-range. Consists of upfront hardware & Backup Software cost, cost of labour to take media offsite and potentially store
Image level Backup to NAS or SAN Onsite	Yes	Yes	No	No	Generally Fast Data is online so quick to access, may need to mount image to recover files depending on backup software	Fast if replacement hardware is available.	Depends on last backup job, but tend to be scheduled to run more frequently – can run as often as every couple of minutes with some software	Mid-range. Consists of upfront hardware & Backup Software cost
Image level Backup to the ‘cloud’	Yes	Yes	Yes / No Data is online, but on a different network, so chances of complete data loss are small, but still feasible (e.g. lost passwords)	Yes	Slow / Fast Depends on the size of the file and bandwidth, also image may need to be mounted depending on backup software but for small files recovery should be fairly quick	Slow / Fast Generally slow for local restore as data needs to be copied or physically brought back to site before restore is performed. If replacement hardware is available, once data is back onsite, image level restore should save time. Has the potential to be fast If online back service allows you to run up a virtual server in their datacentre and point users to that server.	Depends on last backup job, may be a nightly backup scheduled to run outside business hours to prevent network congestion, or could be incrementals scheduled to run as often as every couple of minutes with some software	Mid-Range. Low or no upfront cost, but ongoing subscription and bandwidth cost, generally more expensive the online file based backup only
Image level backup to NAS or SAN Onsite, then to Removable media (tape, external HDD, RDX, Flash drive) taken offsite. (D2D2T)	Yes	Yes	Yes	Yes	Generally Fast Data is online so quick to access, may need to mount image to recover files depending on backup software	Fast if replacement hardware is available.	Depends on last backup job, but tend to be scheduled to run more frequently – can run as often as every couple of minutes with some software for near CDP	Mid-range. Consists of upfront hardware & Backup Software cost
Real time Replication & Failover to NAS or SAN Onsite with backup server or to backup server onsite	Yes	No – with Real time replication changes are tracked and replicated real-time, so if a user deleted a file on the production server, it would also be deleted on the backup server	No	No	Individual files can’t be generally recovered if they have been corrupted or accidentally deleted as changes will be replicated real time.	Very Fast / nearly instantaneous	Zero, changes are replicated in real time, so no data loss since last backup	Mid-high range. Consists of upfront hardware & replication Software cost.
Real time Replication & Failover to NAS or SAN Offsite with backup server or to backup server Offsite	Yes	No – with Real time replication changes are tracked and replicated real-time, so if a user deleted a file on the production server, it would also be deleted on the backup server	Yes / No Data is online, but on a different network, so chances of complete data loss are small, but still feasible	Yes	Individual files can’t be generally recovered if they have been corrupted or accidentally deleted as changes will be replicated real time.	Very Fast / nearly instantaneous	Zero, changes are replicated in real time, so no data loss since last backup	Generally High, Hardware required includes multiple disk arrays and backup servers. Software to drive replication and failover. Ongoing cost of bandwidth between main site and DR Site.
Real time Replication & Failover to NAS or SAN Offsite with backup server or to backup server Offsite. Plus Backup of sever(s) to disk, then to removable media.	Yes	Yes	Yes	Yes	Fast	Very Fast / nearly instantaneous	Zero, changes are replicated in real time, so no data loss since last backup	Expensive. Hardware required includes multiple disk arrays. backup servers. and tape dirves or similar. Software to drive replication and failover, plus licences for backup software. Ongoing cost of bandwidth between main site and DR Site.