# sync

Enables file syncing capability of omfile.

This parameter applies to omfile: File Output Module.

Name:

  sync

Scope:

  action

Type:

  boolean

Default:

  action=off

Required?:

  no

Introduced:

  at least 5.x, possibly earlier

## Description

Enables file syncing capability of omfile.

When enabled, rsyslog does a sync to the data file as well as the directory it resides after processing each batch. There currently is no way to sync only after each n-th batch.

Enabling sync causes a severe performance hit. Actually, it slows omfile so much down, that the probability of losing messages increases. In short, you should enable syncing only if you know exactly what you do, and fully understand how the rest of the engine works, and have tuned the rest of the engine to lossless operations.

## Action usage

    action(type="omfile" sync="...")

## Notes

- Legacy documentation referred to the type as `binary`; this maps to `boolean`.

### Legacy names (for reference)

Historic names/directives for compatibility. Do not use in new configs.

- $ActionFileEnableSync — maps to sync (status: legacy)

## See also

See also omfile: File Output Module.

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