shardingState
shardingState
-
shardingState
is an admin command that reports ifmongod
is a member of a sharded cluster. To run the command, you must run against theadmin
database. Seedb.adminCommand()
.
Syntax
The command has the following syntax:
db.adminCommand(
{
shardingState: 1
}
)
Behavior
For shardingState
to detect that a mongod
is a member of a sharded cluster, the mongod
must satisfy the following conditions:
- the
mongod
is a primary member of a replica set, and - the
mongod
instance is a member of a sharded cluster.
If shardingState
detects that a mongod
is a member of a sharded cluster, shardingState
returns a document that resembles the following prototype:
{
"enabled" : true,
"configServer" : "<configdb-string>",
"shardName" : "<string>",
"shardHost" : "string:",
"versions" : {
"<database>.<collection>" : {
"placementVersion": Timestamp({ t: 1, i: 1024 }),
"timestamp": Timestamp({ t: 1682444810, i: 8 })
},
"<database>.<collection>" : {
"placementVersion": Timestamp({ t: 0, i: 0 }),
"timestamp": Timestamp({ t: 0, i: 0 })
}
},
"ok" : 1,
"$clusterTime" : {
"clusterTime" : Timestamp({ t: 1682457265, i: 1 }),
"signature" : {
"hash" : BinData(0,"B2ViX7XLzFLS5Fl9XEuFXbwKIM4="),
"keyId" : NumberLong("6488045157173166092")
}
},
"operationTime" : Timestamp({ t: 1682457260, i: 1 })
}
Otherwise, shardingState
will return the following document:
{
"enabled" : false,
"ok" : 1,
"$clusterTime" : {
"clusterTime" : Timestamp({t:1510716515, i: 1}),
"signature" : {
"hash" : BinData(0,"B2ViX7XLzFLS5Fl9XEuFXbwKIM4="),
"keyId" : NumberLong("6488045157173166092")
}
},
"operationTime" : Timestamp({t: 1510716515, i: 1})
}
The response from shardingState
when used with a config server is:
{
"enabled" : false,
"ok" : 1,
"operationTime" : Timestamp({t: 1510767613, i: 1}),
"$gleStats" : {
"lastOpTime" : Timestamp({t: 0, i: 0}),
"electionId" : ObjectId("7fffffff0000000000000001")
},
"$clusterTime" : {
"clusterTime" : Timestamp({t: 1510767613, i: 1}),
"signature" : {
"hash" : BinData(0,"IwBZ4SZjIMI5NdM62NObV/R31GM="),
"keyId" : NumberLong("6488693018630029321")
}
}
}
mongos
instances do not provide the shardingState
.
This command obtains a write lock on the affected database and will block other operations until it has completed; however, the operation is typically short lived.