CDCR API | Apache Solr Reference Guide 7.2

The CDCR API is used to control and monitor the replication process. Control actions are performed at a collection level, i.e., by using the following base URL for API calls: http://localhost:8983/solr/<collection>/cdcr.

Monitor actions are performed at a core level, i.e., by using the following base URL for API calls: http://localhost:8983/solr/<core>/cdcr.

Currently, none of the CDCR API calls have parameters.

API Entry Points

Control

<collection>/cdcr?action=STATUS: Returns the current state of CDCR.
<collection>/cdcr?action=START: Starts CDCR replication
<collection>/cdcr?action=STOP: Stops CDCR replication.
<collection>/cdcr?action=ENABLEBUFFER: Enables the buffering of updates.
<collection>/cdcr?action=DISABLEBUFFER: Disables the buffering of updates.

Monitoring

core/cdcr?action=QUEUES: Fetches statistics about the queue for each replica and about the update logs.
core/cdcr?action=OPS: Fetches statistics about the replication performance (operations per second) for each replica.
core/cdcr?action=ERRORS: Fetches statistics and other information about replication errors for each replica.

Control Commands

CDCR STATUS

solr/<collection>/cdcr?action=STATUS

CDCR Status Example

Input

http://localhost:8983/solr/techproducts/cdcr?action=STATUS

Output

{
  "responseHeader": {
  "status": 0,
  "QTime": 0
  },
  "status": {
  "process": "stopped",
  "buffer": "enabled"
  }
}

ENABLEBUFFER

solr/<collection>/cdcr?action=ENABLEBUFFER

Enable Buffer Example

Input

http://localhost:8983/solr/techproducts/cdcr?action=ENABLEBUFFER

Output

{
  "responseHeader": {
  "status": 0,
  "QTime": 0
  },
  "status": {
  "process": "started",
  "buffer": "enabled"
  }
}

DISABLEBUFFER

solr/<collection>/cdcr?action=DISABLEBUFFER

Disable Buffer Example

Input

http://localhost:8983/solr/techproducts/cdcr?action=DISABLEBUFFER

Output

{
  "responseHeader": {
  "status": 0,
  "QTime": 0
  },
  "status": {
  "process": "started",
  "buffer": "disabled"
  }
}

CDCR START

solr/<collection>/cdcr?action=START

CDCR Start Examples

Input

http://localhost:8983/solr/techproducts/cdcr?action=START

Output

{
  "responseHeader": {
  "status": 0,
  "QTime": 0
  },
  "status": {
  "process": "started",
  "buffer": "enabled"
  }
}

CDCR STOP

solr/<collection>/cdcr?action=STOP

CDCR Stop Examples

Input

http://localhost:8983/solr/techproducts/cdcr?action=STOP

Output

{
  "responseHeader": {
  "status": 0,
  "QTime": 0
  },
  "status": {
  "process": "stopped",
  "buffer": "enabled"
  }
}

CDCR Monitoring Commands

QUEUES

solr/<core>/cdcr?action=QUEUES

QUEUES Response

The output is composed of a list “queues” which contains a list of (ZooKeeper) Target hosts, themselves containing a list of Target collections. For each collection, the current size of the queue and the timestamp of the last update operation successfully processed is provided. The timestamp of the update operation is the original timestamp, i.e., the time this operation was processed on the Source SolrCloud. This allows an estimate the latency of the replication process.

The “queues” object also contains information about the update logs, such as the size (in bytes) of the update logs on disk (tlogTotalSize), the number of transaction log files (tlogTotalCount) and the status of the update logs synchronizer (updateLogSynchronizer).

QUEUES Examples

Input

http://localhost:8983/solr/<replica_name>/cdcr?action=QUEUES

Output

{
  "responseHeader":{
    "status": 0,
    "QTime": 1
  },
  "queues":{
    "127.0.0.1: 40342/solr":{
    "Target_collection":{
        "queueSize": 104,
        "lastTimestamp": "2014-12-02T10:32:15.879Z"
      }
    }
  },
  "tlogTotalSize":3817,
  "tlogTotalCount":1,
  "updateLogSynchronizer": "stopped"
}

OPS

solr/<core>/cdcr?action=OPS

OPS Response

Provides the average number of operations as a sum and broken down by adds/deletes.

OPS Examples

Input

http://localhost:8983/solr/<replica_name>/cdcr?action=OPS

Output

{
  "responseHeader":{
    "status":0,
    "QTime":1
  },
  "operationsPerSecond":{
    "127.0.0.1: 59661/solr":{
      "Target_collection":{
          "all": 297.102944952749052,
          "adds": 297.102944952749052,
          "deletes": 0.0
      }
    }
  }
}

ERRORS

solr/<core>/cdcr?action=ERRORS

ERRORS Response

Provides the number of consecutive errors encountered by the replicator thread, the number of bad requests or internal errors since the start of the replication process, and a list of the last errors encountered ordered by timestamp.

ERRORS Examples

Input

http://localhost:8983/solr/<replica_name>/cdcr?action=ERRORS

Output

{
  "responseHeader":{
    "status":0,
    "QTime":2
  },
  "errors": {
    "127.0.0.1: 36872/solr":{
      "Target_collection":{
        "consecutiveErrors":3,
        "bad_request":0,
        "internal":3,
        "last":{
          "2014-12-02T11:04:42.523Z":"internal",
          "2014-12-02T11:04:39.223Z":"internal",
          "2014-12-02T11:04:38.22Z":"internal"
        }
      }
    }
  }
}

Cross Data Center Replication Operations SolrCloud Autoscaling