Monitoring a Self-Managed MongoDB Deployment监控自我管理的MongoDB部署

Monitoring Strategies监控策略

MongoDB provides various methods for collecting data about the state of a running MongoDB instance:MongoDB提供了各种方法来集合有关正在运行的MongoDB实例状态的数据：

• MongoDB distributes a set of utilities that provides real-time reporting of database activities.MongoDB分发了一组实用程序，提供数据库活动的实时报告。
• MongoDB provides various database commands that return statistics regarding the current database state with greater fidelity.MongoDB提供各种数据库命令，以更高的保真度返回有关当前数据库状态的统计信息。
• MongoDB Atlas is a cloud-hosted database-as-a-service for running, monitoring, and maintaining MongoDB deployments.是一种云托管的数据库即服务，用于运行、监控和维护MongoDB部署。
• MongoDB Cloud Manager is a hosted service that monitors running MongoDB deployments to collect data and provide visualization and alerts based on that data.是一种托管服务，用于监控正在运行的MongoDB部署，以集合数据并基于该数据提供可视化和警报。
• MongoDB Ops Manager is an on-premises solution available in MongoDB Enterprise Advanced that monitors running MongoDB deployments to collect data and provide visualization and alerts based on that data.MongoDB Ops Manager是MongoDB Enterprise Advanced中提供的本地解决方案，它监控正在运行的MongoDB部署以集合数据，并根据这些数据提供可视化和警报。

Each strategy can help answer different questions and is useful in different contexts. These methods are complementary.每种策略都可以帮助回答不同的问题，在不同的情况下都很有用。这些方法是互补的。

MongoDB Reporting ToolsMongoDB报告工具

This section provides an overview of the reporting methods distributed with MongoDB. It also offers examples of the kinds of questions that each method is best suited to help you address.本节概述了随MongoDB分发的报告方法。它还提供了每种方法最适合帮助您解决的问题的示例。

Process Logging进程日志记录

During normal operation, mongod and mongos instances report a live account of all server activity and operations to either standard output or a log file. The following runtime settings control these options.在正常运行期间，mongod和mongos实例会向标准输出或日志文件报告所有服务器活动和操作的实时帐户。以下运行时设置控制这些选项。

• quiet. Limits the amount of information written to the log or output.。限制写入日志或输出的信息量。
• verbosity. Increases the amount of information written to the log or output. 。增加写入日志或输出的信息量。You can also modify the logging verbosity during runtime with the logLevel parameter or the db.setLogLevel() method in the shell.您还可以在运行时使用logLevel参数或shell中的db.setLogLevel()方法修改日志记录的详细程度。
• path. Enables logging to a file, rather than the standard output. You must specify the full path to the log file when adjusting this setting.。允许记录到文件，而不是标准输出。调整此设置时，必须指定日志文件的完整路径。
• logAppend. Adds information to a log file instead of overwriting the file.。将信息添加到日志文件中，而不是覆盖该文件。

mongod -v --logpath /var/log/mongodb/server1.log --logappend

The following database commands also affect logging:以下数据库命令也会影响日志记录：

• getLog. Displays recent messages from the mongod process log.。显示mongod进程日志中的最新消息。
• logRotate. Rotates the log files for mongod processes only. 。仅旋转mongod进程的日志文件。See Rotate Log Files.请参见旋转日志文件。

db.clients.insertOne( { "name" : "Joe", "PII" : "Sensitive Information" } )

{
   "t": { "$date": "2024-07-19T15:36:55.024-07:00" },
   "s": "I",
   "c": "COMMAND",
   ...
   "attr": {
      "type": "command",
      ...
      "appName": "mongosh 2.2.10",
      "command": {
         "insert": "clients",
         "documents": [
            {
               "name": "Joe",
               "PII": "Sensitive Information",
               "_id": { "$oid": "669aea8792c7fd822d3e1d8c" }
            }
         ],
         "ordered": true,
         ...
      }
      ...
   }
}

{
   "t": { "$date": "2024-07-19T15:36:55.024-07:00" },
   "s": "I",
   "c": "COMMAND",
   ...
   "attr": {
      "type": "command",
      ...
      "appName": "mongosh 2.2.10",
      "command": {
         "insert": "###",
         "documents": [
            {
               "name": "###",
               "PII": "###",
               "_id": "###"
            }
         ],
         "ordered": "###",
         ...
      }
      ...
   }
}

Diagnosing Performance Issues诊断性能问题

As you develop and operate applications with MongoDB, you may want to analyze the performance of the database as the application. MongoDB Performance discusses some of the operational factors that can influence performance.当您使用MongoDB开发和操作应用程序时，您可能希望分析数据库作为应用程序的性能。MongoDB性能讨论了可能影响性能的一些操作因素。

Replication and Monitoring复制和监控

Beyond the basic monitoring requirements for any MongoDB instance, for replica sets, administrators must monitor replication lag. "Replication lag" refers to the amount of time that it takes to copy (i.e. replicate) a write operation on the primary to a secondary. Some small delay period may be acceptable, but significant problems emerge as replication lag grows, including:除了对任何MongoDB实例的基本监控要求外，对于副本集，管理员还必须监控复制延迟。“复制滞后”是指将主服务器上的写入操作复制到辅助服务器所需的时间。一些小的延迟期可能是可以接受的，但随着复制延迟的增加，会出现重大问题，包括：

• Growing cache pressure on the primary.主服务器上的缓存压力越来越大。
• Operations that occurred during the period of lag are not replicated to one or more secondaries. If you're using replication to ensure data persistence, exceptionally long delays may impact the integrity of your data set.在延迟期间发生的操作不会复制到一个或多个次级服务器。如果您使用复制来确保数据持久性，那么异常长的延迟可能会影响数据集的完整性。

• If the replication lag exceeds the length of the operation log (oplog) then MongoDB will have to perform an initial sync on the secondary, copying all data from the primary and rebuilding all indexes. 如果复制延迟超过操作日志（oplog）的长度，那么MongoDB将不得不在辅助服务器上执行初始同步，从主服务器复制所有数据并重建所有索引。[1] This is uncommon under normal circumstances, but if you configure the oplog to be smaller than the default, the issue can arise.在正常情况下，这并不常见，但如果将oplog配置为小于默认值，则可能会出现问题。

  Note

  The size of the oplog is only configurable during the first run using the --oplogSize argument to the mongod command, or preferably, the oplogSizeMB setting in the MongoDB configuration file. oplog的大小只能在第一次运行时使用mongod命令的--oplogSize参数进行配置，或者最好使用MongoDB配置文件中的oplogSizeMB设置。If you do not specify this on the command line before running with the --replSet option, mongod will create a default sized oplog.如果在使用--replSet选项运行之前没有在命令行中指定此选项，mongod将创建一个默认大小的oplog。

  By default, the oplog is 5 percent of total available disk space on 64-bit systems. For more information about changing the oplog size, see the Change the Oplog Size of Self-Managed Replica Set Members.默认情况下，oplog占64位系统上总可用磁盘空间的5%。有关更改oplog大小的更多信息，请参阅更改自我管理副本集成员的oplog大小。

rs.status()

Sharding and Monitoring分片和监控

In most cases, the components of sharded clusters benefit from the same monitoring and analysis as all other MongoDB instances. In addition, clusters require further monitoring to ensure that data is effectively distributed among nodes and that sharding operations are functioning appropriately.

use config
db.locks.find()

db.locks.find( { _id : "balancer" } )

Storage Node Watchdog存储节点监视器

The Storage Node Watchdog monitors the following MongoDB directories to detect filesystem unresponsiveness:存储节点监视器监视以下MongoDB目录以检测文件系统无响应：

• The --dbpath directory
• The journal directory inside the --dbpath directory
• The directory of --logpath file
• The directory of --auditPath file

By default, the Storage Node Watchdog is disabled. You can only enable the Storage Node Watchdog on a mongod at startup time by setting the watchdogPeriodSeconds parameter to an integer greater than or equal to 60. 默认情况下，存储节点监视器处于禁用状态。您只能在启动时通过将watchdogPeriodSeconds参数设置为大于或等于60的整数来启用mongod上的存储节点监视器。However, once enabled, you can pause the Storage Node Watchdog and restart during runtime. See watchdogPeriodSeconds parameter for details.但是，一旦启用，您可以暂停存储节点监视器并在运行时重新启动。有关详细信息，请参阅watchdogPeriodSeconds参数。

If any of the filesystems containing the monitored directories become unresponsive, the Storage Node Watchdog terminates the mongod and exits with a status code of 61. 如果包含受监视目录的任何文件系统变得没有响应，存储节点监视器将终止mongod并退出，状态代码为61。If the mongod is the primary of a replica set, the termination initiates a failover, allowing another member to become primary.如果mongod是副本集的主成员，则终止会启动故障转移，允许另一个成员成为主成员。

Once a mongod has terminated, it may not be possible to cleanly restart it on the same machine.一旦mongod终止，可能无法在同一台机器上干净地重新启动它。

The maximum time the Storage Node Watchdog can take to detect an unresponsive filesystem and terminate is nearly twice the value of watchdogPeriodSeconds.存储节点监视器检测到无响应的文件系统并终止所需的最长时间几乎是watchdogPeriodSeconds值的两倍。