/path/to//bin/mongo  --host xx.xx.xx.xx:27017   -u  username  -p 'password'  --authenticationDatabase=admin

> rs.printReplicationInfo()   
configured oplog size:   51200MB
log length start to end: 24019311secs (6672.03hrs)
oplog first event time:  Mon Dec 06 2021 15:28:16 GMT+0800 (CST)
oplog last event time:   Sat Sep 10 2022 15:30:07 GMT+0800 (CST)
now:                     Sat Sep 10 2022 15:30:09 GMT+0800 (CST)



> db.getReplicationInfo() 
{
    "logSizeMB" : 51200,
    "usedMB" : 6221.35,
    "timeDiff" : 24019341,
    "timeDiffHours" : 6672.04,
    "tFirst" : "Mon Dec 06 2021 15:28:16 GMT+0800 (CST)",
    "tLast" : "Sat Sep 10 2022 15:30:37 GMT+0800 (CST)",
    "now" : "Sat Sep 10 2022 15:30:38 GMT+0800 (CST)"
}


> db.printSlaveReplicationInfo()
source: 192.168.69.136:27020
    syncedTo: Sat Sep 10 2022 15:33:11 GMT+0800 (CST)
    0 secs (0 hrs) behind the primary 

参考

MongoDB副本集的工作原理
https://www.cnblogs.com/wilber2013/p/4154406.html

MongoDB 更改 Oplog Size 大小
https://blog.51cto.com/professor/2377323
https://mongoing.com/docs/tutorial/change-oplog-size.html

MongoDB Oplog窗口时间
https://www.modb.pro/db/55869

replSetResizeOplog
https://www.mongodb.com/docs/upcoming/reference/command/replSetResizeOplog/#dbcmd.replSetResizeOplog

replSetResizeOplog
https://www.mongodb.com/docs/v4.2/reference/command/replSetResizeOplog/

在集群中增加或者删除分片
https://www.bookstack.cn/read/piaosanlang-mongodb/996d2bed6b85bea7.md

MongoDB Oplog 详解
https://www.cnblogs.com/operationhome/p/10688798.html

Mongodb 复制的纽带–Oplog
https://www.bookstack.cn/read/piaosanlang-mongodb/e921df26646d53f2.md

MongoDB副本集添加新的节点
https://blog.csdn.net/csdnhsh/article/details/116333686