GFS Retention¶
GFS (Grandfather-Father-Son) is a long-term retention mechanism used by Veeam Backup & Replication to keep selected tape copies for different periods.
Within Cloud4You Tape as a Service, GFS makes it possible to build a multi-level archive policy, for example:
This means that not every copy has to be retained for the same length of time.
GFS for tape
In Veeam, tape GFS provides five independent levels:
Each level can have its own retention period and its own media settings.
How does GFS work in Tape as a Service?¶
For Cloud4You, the source data is a backup stored in the Cloud Repository.
Veeam on the Service Provider side then writes the appropriate archive point to tape.
Customer backup
│
▼
Cloud4You Cloud Repository
│
▼
Tenant Backup to Tape
│
▼
GFS Media Pool
│
├── Daily
├── Weekly
├── Monthly
├── Quarterly
└── Yearly
For Tenant Backup to Tape, Veeam requires:
The jobs and GFS policy are managed by Cloud4You on the Service Provider infrastructure.
GFS Media Pool¶
A GFS Media Pool is a special Media Pool intended for multi-level tape archiving.
Veeam automatically creates separate media sets:
| Media Set | Purpose |
|---|---|
| Daily | daily copies |
| Weekly | weekly copies |
| Monthly | monthly copies |
| Quarterly | quarterly copies |
| Yearly | yearly copies |
Not every level has to be used.
For example, a Cloud4You policy may use only:
without:
Retention for each level¶
Each media set can have its own period during which data is protected from overwrite.
Example:
Weekly
Retention: 4 weeks
Monthly
Retention: 12 months
Quarterly
Retention: 24 months
Yearly
Retention: 5 years
Quarterly
In a service description, quarterly retention can be expressed, for example, as 8 quarters, while technically Veeam stores Quarterly retention in months.
Example:
What does retention mean?¶
Retention defines the period during which data stored on tape is protected from overwrite.
Example:
means that data in the weekly media set is protected for four weeks.
After the retention period expires, the tape may be reused according to the Media Pool configuration and service policy.
Warning
Retention expiration does not mean that the data is immediately physically overwritten. It means that Veeam may reuse the medium when needed.
Daily¶
The:
level is intended for short-term daily archive points.
Example:
In a typical Cloud4You Tape as a Service configuration, the Daily level does not have to be used if the main purpose of the service is archiving:
Note
Veeam indicates that a Daily Media Set typically stores daily changes, while the full backup needed for a complete chain may be stored in a Weekly or Monthly Media Set. Therefore, Daily retention design must take the complete GFS chain into account.
Weekly¶
The:
level keeps weekly backup copies.
Example:
which means:
After the next set is created, the oldest tape whose retention has expired may be reused.
Another option:
keeps approximately two months of weekly history.
Monthly¶
The:
level keeps one copy for the selected monthly period.
Example:
which means:
Monthly copies can be retained significantly longer than weekly copies.
Quarterly¶
The:
level is available in Tape GFS and allows quarterly copies to be retained.
Example service description:
which technically corresponds to:
Longer periods are also possible:
which means three years of quarterly copies.
Important
Quarterly is available in GFS for tape. Do not confuse it with the classic GFS policy for a Backup Copy Job on a disk repository, where Weekly, Monthly, and Yearly cycles are commonly used.
Yearly¶
The:
level allows annual copies to be retained for many years.
Example:
or:
Yearly copies can be used for long-term data archiving.
Example basic policy¶
A simple customer option:
Flow:
This keeps a short weekly history and a longer monthly history.
Example extended policy¶
In simplified form:
Note
The actual number of tapes does not have to match the number of retention points 1:1. One media set may use one or several tapes depending on the amount of data and tape capacity.
Example long-term policy¶
This model makes it possible to retain:
What happens when schedules overlap?¶
Several GFS cycles can fall on the same day.
Example:
may be simultaneously:
Veeam does not create four identical copies.
The following hierarchy applies:
The highest, longest-term level has priority.
In the example above, Veeam creates:
and skips the other levels for that date.
This reduces unnecessary duplication of data on tape.
How is the backup selected for archiving?¶
A GFS Tape Job does not back up a production machine directly.
The source is existing backup files.
For:
Veeam uses a full backup or creates the appropriate full point for tape archiving according to the GFS mechanism.
Daily processing works differently and depends on the existing backup chain.
Retention and overwrite¶
The purpose of retention is to prevent a medium from being reused too early.
Flow:
Write to tape
↓
Retention active
↓
Tape protected from overwrite
↓
Retention ends
↓
Medium may be reused
Example:
A tape containing a monthly dataset remains protected for the configured period.
Append and new media sets¶
For each GFS level, Cloud4You can configure how media should be used.
Possible approaches include:
- appending data to an existing media set,
- starting a new media set,
- using a separate tape set for a specific period.
The selected approach depends on:
- data size,
- schedule,
- required retention,
- number of available media,
- requirements for taking tapes offline.
Taking long-term copies offline¶
For:
it is often worth considering physical tape export from the active library after the job completes.
Example:
Weekly
↓
remains in active rotation
Monthly
↓
Export
↓
offline storage
Quarterly
↓
Export
↓
offline storage
Yearly
↓
Export
↓
long-term storage
Tenant Backup to Tape allows selected media sets to be exported automatically after the job finishes.
Media Vault¶
Veeam provides:
for tracking media stored outside the library.
For GFS, moving offline tapes to a Vault can be configured individually for specific media sets.
Example:
Weekly
Vault: disabled
Monthly
Vault: ARCHIVE
Quarterly
Vault: ARCHIVE
Yearly
Vault: LONG-TERM-ARCHIVE
Info
Media Vault in Veeam is a logical mechanism for recording the tape location. Physical media-storage rules are part of the Cloud4You service.
How to choose retention¶
Retention should be based on the organization's actual requirements.
When designing a policy, consider:
- business requirements,
- legal and contractual requirements,
- time required to detect data loss,
- ransomware risk,
- audit requirements,
- amount of data,
- media cost,
- required archive period.
Not every level always needs to be retained.
Example — small company¶
A simple additional data-protection layer.
Example — standard policy¶
This provides:
- current weekly copies,
- monthly history,
- two years of quarterly points.
Example — long-term archive¶
This option may be appropriate for environments with formal long-term data-retention requirements.
How many tapes are required?¶
The number of media cannot be calculated only from:
The number of tapes is also affected by:
- backup size,
- LTO generation,
- compression,
- data structure,
- number of systems,
- media-set creation method,
- append rules,
- media export.
Example:
may require more than one tape for each monthly GFS point.
Before service activation, Cloud4You selects the required number of media based on the actual data volume and retention.
GFS and WORM¶
Veeam also supports:
for compatible media and libraries.
With WORM, data written to the medium cannot be overwritten in the same way as on standard rewritable tapes.
WORM requires a separate:
Note
Availability of WORM in Tape as a Service depends on Cloud4You infrastructure and the service scope. If WORM media is required, this must be agreed before archiving is started.
Tape GFS vs GFS in Backup Copy Job¶
These are two different mechanisms.
Backup Copy Job¶
Typical GFS for a disk repository:
Tape GFS¶
GFS Media Pool for tape:
Therefore, Tape as a Service also provides the:
level for retaining quarterly copies.
Example Cloud4You policy¶
Example configuration for a customer requiring multi-level retention:
Tape as a Service
Weekly:
every week
retention 4 weeks
remains in active rotation
Monthly:
once per month
retention 12 months
export after writing
Quarterly:
once per quarter
retention 24 months
export after writing
Yearly:
once per year
retention 5 years
export after writing
Flow:
Cloud Repository
│
▼
GFS Tape
│
├── Weekly ──────── 4 weeks
│
├── Monthly ─────── 12 months ──► offline
│
├── Quarterly ───── 24 months ──► offline
│
└── Yearly ──────── 5 years ────► offline
Changing retention¶
The GFS policy can be changed within the scope of the service.
Before shortening or extending retention, assess:
- existing media sets,
- data already written to tape,
- overwrite-protection requirements,
- media availability,
- impact on the future schedule.
Warning
Changing a retention policy should not be treated as a way to immediately delete data already written to physical media.
Best practices¶
When designing Tape GFS, we recommend:
- not retaining every copy for the same long period,
- using Weekly for short-term history,
- Monthly for medium-term history,
- Quarterly and Yearly for long-term archiving,
- exporting important copies outside the active library,
- keeping a media inventory,
- testing restores regularly,
- periodically reviewing whether the policy still matches organizational requirements.
Important
Long retention alone does not guarantee effective Disaster Recovery. Tape copies should be periodically verified through an actual restore operation.
Summary¶
Tape GFS provides a flexible policy:
Example Tape as a Service option:
Each level can independently be:
- enabled or disabled,
- assigned its own retention,
- configured with its own Media Set,
- exported and stored offline.
Related guides¶
- About Tape as a Service
- One-time Backup
- Recurring Backup
- Available Retention Options
- Restoring Data from Tape
- Tape Security and Storage
- Ordering the Service