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db.getReplicationInfo()![](/docs/v5.3/assets/link.svg)
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Definition![](/docs/v5.3/assets/link.svg)
db.getReplicationInfo()
Returns a document with the status of the replica set, using data polled from the oplog. Use this output when diagnosing issues with replication.
Output![](/docs/v5.3/assets/link.svg)
db.getReplicationInfo.logSizeMB
Returns the total size of the oplog in megabytes. This refers to the total amount of space allocated to the oplog rather than the current size of operations stored in the oplog.
Starting in MongoDB 4.0, the oplog can grow past its configured size limit to avoid deleting the
majority commit point
.
db.getReplicationInfo.usedMB
Returns the total amount of space used by the oplog in megabytes. This refers to the total amount of space currently used by operations stored in the oplog rather than the total amount of space allocated.
db.getReplicationInfo.oplogMainRowCount
Only present when there are no entries in the oplog. Reports a the number of items or rows in the oplog (e.g.
0
).
db.getReplicationInfo.timeDiff
Returns the difference between the first and last operation in the oplog, represented in seconds.
Only present if there are entries in the oplog.
db.getReplicationInfo.timeDiffHours
Returns the difference between the first and last operation in the oplog, rounded and represented in hours.
Only present if there are entries in the oplog.
db.getReplicationInfo.tFirst
Returns a time stamp for the first (i.e. earliest) operation in the oplog. Compare this value to the last write operation issued against the server.
Only present if there are entries in the oplog.
db.getReplicationInfo.tLast
Returns a time stamp for the last (i.e. latest) operation in the oplog. Compare this value to the last write operation issued against the server.
Only present if there are entries in the oplog.
db.getReplicationInfo.now
Returns a timestamp that reflects the current time. The shell process generates this value, and the datum may differ slightly from the server time if you're connecting from a remote host as a result. Equivalent to
Date()
.Only present if there are entries in the oplog.