November 2021
Intermediate to advanced
410 pages
12h 1m
Chinese
Content preview from MongoDB权威指南（第3版）
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228
｜
第
13
章
这样，未冻结的成员就可以在需要时进行选举了。
也可以运行
rs.freeze(0)
将已经退位的主节点解冻。
13.4
监控复制
能够监控副本集的状态是很重要的：不仅要监控是否所有成员都已启动，还要监控它们所
处的状态以及数据的新旧程度。可以使用一些命令来查看副本集信息。包括
Atlas
、
Cloud
Manager
和
Ops
Manager
（参见第
22
章）在内的
MongoDB
托管服务和管理工具也提供了
针对复制关键指标的监控机制。
与复制相关的故障通常是暂时的，比如，一台服务器之前无法连接到另一台服务器，但现
在可以了。查看此类问题最简单的方法就是查看日志。确保自己知道日志的保存位置以及
它们确实被保存下来了，并且可以访问到它们。
13.4.1
获取状态
replSetGetStatus
是一个非常有用的命令，它可以获取副本集中每个成员的当前信息（从
正在运行此命令的成员的视角）。可以在
shell
中使用这个命令的辅助函数：
> rs.status()
{
"set" : "replset",
"date" : ISODate("2019-11-02T20:02:16.543Z"),
"myState" : 1,
"term" : NumberLong(1),
"heartbeatIntervalMillis" : NumberLong(2000),
"optimes" : {
"lastCommittedOpTime" : {
"ts" : Timestamp(1478116934, ...
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