mirror of https://gitee.com/bigwinds/arangodb
36 lines
1.5 KiB
Markdown
36 lines
1.5 KiB
Markdown
---
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layout: default
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description: Previous versions of ArangoDB allowed starting, stopping and configuring thereplication logger
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---
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Replication Logger Commands
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===========================
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Previous versions of ArangoDB allowed starting, stopping and configuring the
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replication logger. These commands are superfluous in ArangoDB 2.2 as all
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data-modification operations are written to the server's write-ahead log and are
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not handled by a separate logger anymore.
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The only useful operations remaining since ArangoDB 2.2 are to query the current state
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of the logger and to fetch the latest changes written by the logger. The operations
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will return the state and data from the write-ahead log.
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<!-- arangod/RestHandler/RestReplicationHandler.cpp -->
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{% docublock get_api_replication_logger_return_state %}
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To query the latest changes logged by the replication logger, the HTTP interface
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also provides the `logger-follow` method.
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This method should be used by replication clients to incrementally fetch updates
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from an ArangoDB database.
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<!-- arangod/RestHandler/RestReplicationHandler.cpp -->
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{% docublock get_api_replication_logger_follow %}
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To check what range of changes is available (identified by tick values), the HTTP
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interface provides the methods `logger-first-tick` and `logger-tick-ranges`.
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Replication clients can use the methods to determine if certain data (identified
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by a tick *date*) is still available on the master.
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{% docublock get_api_replication_logger_first_tick %}
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{% docublock get_api_replication_logger_tick_ranges %}
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