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- flushRouterConfig
flushRouterConfig¶
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Definition¶
-
flushRouterConfig
¶ flushRouterConfig
marks the cached routing table for a sharded cluster as stale, causing the next operation that requests the routing table to refresh the cache. Management of the routing table cache is generally handled automatically by the cluster. You should only need to run theflushRouterConfig
command manually in specific instances, as indicated under Considerations.
Note
Starting in MongoDB 4.4, running flushRouterConfig
is no longer required after executing the movePrimary
or
dropDatabase
commands. These two commands now
automatically refresh a sharded cluster’s routing table as needed
when run.
Syntax¶
Starting in MongoDB 4.0.6 (and 3.6.11), the
flushRouterConfig
is available on both
mongos
and mongod
instances, and has the
following syntax:
Flush the cache for a specified collection when passed in a collection namespace parameter:
Flush the cache for a specified database and all of its collections when passed in a database namespace parameter:
Flush the cache for all databases and their collections when run without a parameter or passed in a non-string scalar value (e.g.
1
):
Note
In MongoDB 4.0.5 and earlier (and 3.6.10 and earlier),
flushRouterConfig
is only available for
mongos
instances and can only flush the cache for all
databases and their collections:
Considerations¶
Generally, a sharded cluster’s routing table is automatically refreshed
as needed as part of normal operation. However, you should manually
issue the flushRouterConfig
command in the following
instances:
- If running MongoDB 4.2 or earlier, after executing the
movePrimary
ordropDatabase
commands. - If running MongoDB 4.2.2 or earlier (or 4.0.14 or earlier), after
manually clearing the
jumbo
flag from a chunk that could not be split (i.e. an indivisible chunk). See Clear jumbo Flag for more information. - Before running the
db.collection.getShardDistribution()
command. This ensures that the command returns the most up-to-date information.