Database Manual / Sharding / Administration

View Cluster Configuration查看群集配置

List Databases列出数据库

To list your databases, query the databases collection in the Config Database. 要列出数据库，请在Config数据库中查询databases集合。Connect mongosh to a mongos instance and run the following operation to get a full list of the databases in your cluster:将mongosh连接到mongos实例，并运行以下操作以获取集群中数据库的完整列表：

use config
db.databases.find()

List Shards列出分片

To list the current set of configured shards, use the listShards command, as follows:要列出当前配置的分片集，请使用listShards命令，如下所示：

db.adminCommand( { listShards : 1 } )

View Cluster Details查看群集详细信息

To view cluster details, issue db.printShardingStatus() or sh.status(). Both methods return the same output.要查看集群详细信息，请发出db.printShardingStatus()或sh.status()。两种方法返回相同的输出。

Example示例

In the following example output from sh.status()在下面的sh.status()输出示例中

  • sharding version displays the version number of the shard metadata.显示分片元数据的版本号。
  • shards displays a list of the mongod instances used as shards in the cluster.显示集群中用作分片的mongod实例列表。
  • databases displays information about all databases in the cluster.显示有关群集中所有数据库的信息。
  • The chunks information for the foo database displays how many chunks are on each shard and displays the range of each chunk.foo数据库的chunks信息显示每个分片上有多少块，并显示每个块的范围。
--- Sharding Status ---
  sharding version: {
    "_id" : 1,
    "minCompatibleVersion" : 5,
    "currentVersion" : 6,
    "clusterId" : ObjectId("59a4443c3d38cd8a0b40316d")
  }
  shards:
    {  "_id" : "shard0000",  "host" : "m0.example.net:27018" }
    {  "_id" : "shard0001",  "host" : "m3.example2.net:27018" }
    {  "_id" : "shard0002",  "host" : "m2.example.net:27018" }
  active mongoses:
    "3.4.7" : 1
  autosplit:
    Currently enabled: yes
   balancer:
    Currently enabled:  yes
    Currently running:  no
    Failed balancer rounds in last 5 attempts:  0
    Migration Results for the last 24 hours:
       1 : Success
  databases:
    { "_id" : "foo", "primary" : "shard0000" }
        foo.contacts
            shard key: { "zip" : 1 }
            unique: false
            balancing: true
            chunks:
                shard0001    2
                shard0002    3
                shard0000    2
            { "zip" : { "$minKey" : 1 } } -->> { "zip" : "56000" } on : shard0001 { "t" : 2, "i" : 0 }
            { "zip" : 56000 } -->> { "zip" : "56800" } on : shard0002 { "t" : 3, "i" : 4 }
            { "zip" : 56800 } -->> { "zip" : "57088" } on : shard0002 { "t" : 4, "i" : 2 }
            { "zip" : 57088 } -->> { "zip" : "57500" } on : shard0002 { "t" : 4, "i" : 3 }
            { "zip" : 57500 } -->> { "zip" : "58140" } on : shard0001 { "t" : 4, "i" : 0 }
            { "zip" : 58140 } -->> { "zip" : "59000" } on : shard0000 { "t" : 4, "i" : 1 }
            { "zip" : 59000 } -->> { "zip" : { "$maxKey" : 1 } } on : shard0000 { "t" : 3, "i" : 3 }
    {  "_id" : "test", "primary" : "shard0000" }