SEASnet Backup and Tape Storage Retention Policies

The following policies are in effect regarding data on SEASnet servers and on user machines that have backup support from SEASnet. These policies apply to both your electronic mail and filesystem data.

These policies are designed to ensure that accidentally deleted data may be retrieved, if necessary, for a reasonable period of time and provide individuals with a clear time table concerning retention of their data. SEASnet recognizes that it is important for users to know that their data is restorable in the event of accidental or catastrophic data loss, but also that data is not being retained beyond a useful period of time.

Background Information

SEASnet provides snapshots of data and email maintained on our servers. "Snapshots" are taken at various intervals during each 24 hour period (see schedule below). Snapshots taken of users data files allow the user to restore data accidentally deleted from their account without intervention from SEASnet (Note: this is only possible with data files - SEASnet staff must intervene for all email restorals). SEASnet maintains approximately one to two weeks worth of snapshots. Step-by-step instructions for restoring deleted files can be found here.

Backup Schedule

Electronic mail data (incoming mail spool directories and all Webmail folders) :

Backup Level	Frequency	Storage	Retention
Full backup	Daily AM (M-F)	On-line	2 weeks
Super incremental	Daily PM (M-F)	Tape	3 months
Full backup	Twice Daily (Sat/Sun)	On-line	2 weeks
Full backup	Every Friday (PM)	Tape	3 months

Snapshots of filesystem data and electronic mail:

Times	Frequency	Storage	Retention
9am-11pm	Every two hours	On-line	24 hours
Midnight	Every day	On-line	8 days
Midnight	Weekly (Sun)	On-line	2 weeks

THESE POLICIES ARE NOT A GUARANTEE THAT DATA WILL NOT BE RETAINED, EITHER INTENTIONALLY OR ACCIDENTALLY, BEYOND THE TIME PERIODS LISTED ABOVE.

Definitions

incremental

backs up files within a filesystem that have changed since the previous incremental backup

super incremental

backs up files, within a filesystem, that have changed since the last full backup of a filesystem - if utilized in conjunction with a full filesystem backup, it enables the complete restoration of a filesystem at the time of the current super incremental backup

full

a backup of all data within a given filesystem - it enables the complete restoration of a filesystem at the time of the current backup

snapshots

snapshots are a feature of the file server used by SEASnet to store user and electronic mail data
they create virtual images of a filesystem and all data at the time the snapshot is created - this enables convenient retrieval of lost data up to the retention time of snapshots