我正在尝试将我的独立MongoDB实例转换为单节点副本集，以便实时迁移到Atlas。我遵循以下程序：https://docs.mongodb.com/manual/tutorial/convert-standalone-to-replica-set/
我采取的步骤是：
$sudo service mongodb stop
$sudo service mongod start
$mongo
>rs.initiate()
{
"info2" : "no configuration explicitly specified -- making one",
"me" : "staging3.domain.io:27017",
"info" : "Config now saved locally. Should come online in about a minute.",
"ok" : 1
}
singleNodeRepl:PRIMARY> rs.status()
{
"set" : "singleNodeRepl",
"date" : ISODate("2020-11-26T00:46:25Z"),
"myState" : 1,
"members" : [
{
"_id" : 0,
"name" : "staging4.domain.io:27017",
"health" : 1,
"state" : 1,
"stateStr" : "PRIMARY",
"uptime" : 1197,
"optime" : Timestamp(1606350415, 1),
"optimeDate" : ISODate("2020-11-26T00:26:55Z"),
"electionTime" : Timestamp(1606350415, 2),
"electionDate" : ISODate("2020-11-26T00:26:55Z"),
"self" : true
}
],
"ok" : 1
}
singleNodeRepl:PRIMARY> db.oplog.rs.find()
{ "ts" : Timestamp(1606350415, 1), "h" : NumberLong(0), "v" : 2, "op" : "n", "ns" : "", "o" : { "msg" : "initiating set" } }
在这一点上，它似乎没有任何问题。然而，我的应用程序无法像以前那样工作。
非常感谢您为解决此问题提供帮助。非常感谢。
编辑：
按照建议，我将replSet包含在配置文件中，而不是将其作为参数传递。这是我的配置文件：
# mongod.conf
#where to log
logpath=/var/log/mongodb/mongod.log
logappend=true
# fork and run in background
fork=true
#port=27017
dbpath=/var/lib/mongo
# location of pidfile
pidfilepath=/var/run/mongodb/mongod.pid
# Listen to local interface only. Comment out to listen on all interfaces.
#bind_ip=127.0.0.1
# Disables write-ahead journaling
# nojournal=true
# Enables periodic logging of CPU utilization and I/O wait
#cpu=true
# Turn on/off security. Off is currently the default
#noauth=true
#auth=true
# Verbose logging output.
verbose=true
# Inspect all client data for validity on receipt (useful for
# developing drivers)
#objcheck=true
# Enable db quota management
#quota=true
# Set oplogging level where n is
# 0=off (default)
# 1=W
# 2=R
# 3=both
# 7=W+some reads
#diaglog=0
# Ignore query hints
#nohints=true
# Enable the HTTP interface (Defaults to port 28017).
#httpinterface=true
# Turns off server-side scripting. This will result in greatly limited
# functionality
#noscripting=true
# Turns off table scans. Any query that would do a table scan fails.
#notablescan=true
# Disable data file preallocation.
#noprealloc=true
# Specify .ns file size for new databases.
# nssize=<size>
# Replication Options
# in replicated mongo databases, specify the replica set name here
replSet=singleNodeRepl
# maximum size in megabytes for replication operation log
#oplogSize=1024
# path to a key file storing authentication info for connections
# between replica set members
#keyFile=/path/to/keyfile
和详细日志文件：看起来一切都很好。但是，我的应用程序无法像以前那样连接到数据库。
2020-11-26T00:26:55.852+0000 [conn1] replSet replSetInitiate admin command received from client
2020-11-26T00:26:55.853+0000 [conn1] replSet info initiate : no configuration specified. Using a default configuration for the set
2020-11-26T00:26:55.853+0000 [conn1] replSet created this configuration for initiation : { _id: "singleNodeRepl", members: [ { _id: 0, host: "staging4.domain.io:27017" } ] }
2020-11-26T00:26:55.853+0000 [conn1] replSet replSetInitiate config object parses ok, 1 members specified
2020-11-26T00:26:55.853+0000 [conn1] getMyAddrs(): [127.0.0.1] [10.20.26.228] [::1] [fe80::8ed:65ff:fe9e:15ab%eth0]
2020-11-26T00:26:55.853+0000 [conn1] getallIPs("staging4.domain.io"): [127.0.0.1]
2020-11-26T00:26:55.853+0000 [conn1] replSet replSetInitiate all members seem up
2020-11-26T00:26:55.853+0000 [conn1] ******
2020-11-26T00:26:55.853+0000 [conn1] creating replication oplog of size: 2570MB...
2020-11-26T00:26:55.853+0000 [conn1] create collection local.oplog.rs { size: 2695574937.6, capped: true, autoIndexId: false }
2020-11-26T00:26:55.853+0000 [conn1] Database::_addNamespaceToCatalog ns: local.oplog.rs
2020-11-26T00:26:55.866+0000 [conn1] ExtentManager::increaseStorageSize ns:local.oplog.rs desiredSize:2146426624 fromFreeList: 0 eloc: 1:2000
2020-11-26T00:26:55.876+0000 [conn1] ExtentManager::increaseStorageSize ns:local.oplog.rs desiredSize:549148160 fromFreeList: 0 eloc: 2:2000
2020-11-26T00:26:55.878+0000 [conn1] ******
2020-11-26T00:26:55.878+0000 [conn1] replSet info saving a newer config version to local.system.replset: { _id: "singleNodeRepl", version: 1, members: [ { _id: 0, host: "staging4.domain.io:27017" } ] }
2020-11-26T00:26:55.878+0000 [conn1] Database::_addNamespaceToCatalog ns: local.system.replset
2020-11-26T00:26:55.878+0000 [conn1] ExtentManager::increaseStorageSize ns:local.system.replset desiredSize:8192 fromFreeList: 0 eloc: 2:20bb8000
2020-11-26T00:26:55.878+0000 [conn1] Database::_addNamespaceToCatalog ns: local.system.replset.$_id_
2020-11-26T00:26:55.878+0000 [conn1] build index on: local.system.replset properties: { v: 1, key: { _id: 1 }, name: "_id_", ns: "local.system.replset" }
2020-11-26T00:26:55.878+0000 [conn1] local.system.replset: clearing plan cache - collection info cache reset
2020-11-26T00:26:55.878+0000 [conn1] allocating new extent
2020-11-26T00:26:55.878+0000 [conn1] ExtentManager::increaseStorageSize ns:local.system.replset.$_id_ desiredSize:131072 fromFreeList: 0 eloc: 2:20bba000
2020-11-26T00:26:55.878+0000 [conn1] added index to empty collection
2020-11-26T00:26:55.878+0000 [conn1] local.system.replset: clearing plan cache - collection info cache reset
2020-11-26T00:26:55.878+0000 [conn1] replSet saveConfigLocally done
2020-11-26T00:26:55.878+0000 [conn1] replSet replSetInitiate config now saved locally. Should come online in about a minute.
2020-11-26T00:26:55.878+0000 [conn1] command admin.$cmd command: replSetInitiate { replSetInitiate: undefined } keyUpdates:0 numYields:0 locks(micros) W:25362 reslen:206 25ms
2020-11-26T00:26:55.879+0000 [conn1] command test.$cmd command: isMaster { isMaster: 1.0, forShell: 1.0 } keyUpdates:0 numYields:0 reslen:270 0ms
2020-11-26T00:27:01.256+0000 [conn1] command admin.$cmd command: replSetGetStatus { replSetGetStatus: 1.0 } keyUpdates:0 numYields:0 reslen:300 0ms
2020-11-26T00:27:01.257+0000 [conn1] command test.$cmd command: isMaster { isMaster: 1.0, forShell: 1.0 } keyUpdates:0 numYields:0 reslen:367 0ms
2020-11-26T00:27:10.688+0000 [conn1] query local.system.replset planSummary: COLLSCAN ntoskip:0 nscanned:1 nscannedObjects:1 keyUpdates:0 numYields:0 locks(micros) r:97 nreturned:1 reslen:126 0ms
2020-11-26T00:27:10.689+0000 [conn1] command test.$cmd command: isMaster { isMaster: 1.0, forShell: 1.0 } keyUpdates:0 numYields:0 reslen:367 0ms
2020-11-26T00:27:28.889+0000 [clientcursormon] connections:1
2020-11-26T00:27:33.333+0000 [conn1] end connection 127.0.0.1:50580 (0 connections now open)
2020-11-26T00:27:57.230+0000 [initandlisten] connection accepted from 127.0.0.1:50582 #2 (1 connection now open)
2020-11-26T00:27:57.230+0000 [conn2] command admin.$cmd command: whatsmyuri { whatsmyuri: 1 } ntoreturn:1 keyUpdates:0 numYields:0 reslen:62 0ms
2020-11-26T00:27:57.232+0000 [conn2] command admin.$cmd command: getLog { getLog: "startupWarnings" } keyUpdates:0 numYields:0 reslen:70 0ms
2020-11-26T00:27:57.233+0000 [conn2] command admin.$cmd command: replSetGetStatus { replSetGetStatus: 1.0, forShell: 1.0 } keyUpdates:0 numYields:0 reslen:300 0ms
2020-11-26T00:28:00.237+0000 [conn2] command admin.$cmd command: serverStatus { serverStatus: 1.0 } keyUpdates:0 numYields:0 locks(micros) r:13 reslen:3402 0ms
2020-11-26T00:28:00.242+0000 [conn2] command admin.$cmd command: replSetGetStatus { replSetGetStatus: 1.0, forShell: 1.0 } keyUpdates:0 numYields:0 reslen:300 0ms
2020-11-26T00:28:16.560+0000 [conn2] end connection 127.0.0.1:50582 (0 connections now open)
2020-11-26T00:32:28.904+0000 [clientcursormon] connections:0
2020-11-26T00:36:32.398+0000 [initandlisten] connection accepted from 127.0.0.1:50588 #3 (1 connection now open)
2020-11-26T00:36:32.398+0000 [conn3] command admin.$cmd command: whatsmyuri { whatsmyuri: 1 } ntoreturn:1 keyUpdates:0 numYields:0 reslen:62 0ms
2020-11-26T00:36:32.399+0000 [conn3] command admin.$cmd command: getLog { getLog: "startupWarnings" } keyUpdates:0 numYields:0 reslen:70 0ms
2020-11-26T00:36:32.400+0000 [conn3] command admin.$cmd command: replSetGetStatus { replSetGetStatus: 1.0, forShell: 1.0 } keyUpdates:0 numYields:0 reslen:300 0ms
2020-11-26T00:36:34.603+0000 [conn3] command admin.$cmd command: replSetGetStatus { replSetGetStatus: 1.0, forShell: 1.0 } keyUpdates:0 numYields:0 reslen:300 0ms
2020-11-26T00:36:37.326+0000 [conn3] query local.oplog.rs planSummary: COLLSCAN ntoreturn:0 ntoskip:0 nscanned:1 nscannedObjects:1 keyUpdates:0 numYields:0 locks(micros) r:66 nreturned:1 reslen:106 0ms
2020-11-26T00:36:37.328+0000 [conn3] command admin.$cmd command: replSetGetStatus { replSetGetStatus: 1.0, forShell: 1.0 } keyUpdates:0 numYields:0 reslen:300 0ms
2020-11-26T00:37:28.832+0000 [initandlisten] connection accepted from 10.20.37.160:54484 #4 (2 connections now open)
2020-11-26T00:37:28.832+0000 [conn4] command admin.$cmd command: isMaster { isMaster: 1, compression: [], client: { driver: { name: "mongo-ruby-driver", version: "2.13.1" }, os: { type: "linux", name: "linux-gnu", architecture: "x86_64" }, platform: "mongoid-6.4.1, Ruby 2.6.5, x86_64-linux, x86_64-pc-linux-gnu" } } keyUpdates:0 numYields:0 reslen:367 0ms
2020-11-26T00:37:28.919+0000 [clientcursormon] connections:2
2020-11-26T00:37:33.568+0000 [initandlisten] connection accepted from 10.20.37.160:54492 #5 (3 connections now open)
2020-11-26T00:37:33.569+0000 [conn5] command admin.$cmd command: isMaster { isMaster: 1, compression: [], client: { driver: { name: "mongo-ruby-driver", version: "2.13.1" }, os: { type: "linux", name: "linux-gnu", architecture: "x86_64" }, platform: "mongoid-6.4.1, Ruby 2.6.5, x86_64-linux, x86_64-pc-linux-gnu" } } keyUpdates:0 numYields:0 reslen:367 0ms
2020-11-26T00:37:36.586+0000 [conn3] end connection 127.0.0.1:50588 (2 connections now open)
2020-11-26T00:39:35.621+0000 [initandlisten] connection accepted from 127.0.0.1:50592 #6 (3 connections now open)
2020-11-26T00:39:35.621+0000 [conn6] command admin.$cmd command: whatsmyuri { whatsmyuri: 1 } ntoreturn:1 keyUpdates:0 numYields:0 reslen:62 0ms
2020-11-26T00:39:35.622+0000 [conn6] command admin.$cmd command: getLog { getLog: "startupWarnings" } keyUpdates:0 numYields:0 reslen:70 0ms
2020-11-26T00:39:35.623+0000 [conn6] command admin.$cmd command: replSetGetStatus { replSetGetStatus: 1.0, forShell: 1.0 } keyUpdates:0 numYields:0 reslen:300 0ms
2020-11-26T00:39:37.589+0000 [conn6] opening db: test
2020-11-26T00:39:37.589+0000 [conn6] query test.oplog.rs planSummary: EOF ntoreturn:0 ntoskip:0 nscanned:0 nscannedObjects:0 keyUpdates:0 numYields:0 locks(micros) W:186 r:19 nreturned:0 reslen:20 0ms
2020-11-26T00:39:37.590+0000 [conn6] command admin.$cmd command: replSetGetStatus { replSetGetStatus: 1.0, forShell: 1.0 } keyUpdates:0 numYields:0 reslen:300 0ms
2020-11-26T00:39:41.891+0000 [conn6] command admin.$cmd command: replSetGetStatus { replSetGetStatus: 1.0, forShell: 1.0 } keyUpdates:0 numYields:0 reslen:300 0ms
2020-11-26T00:39:43.266+0000 [conn6] query local.oplog.rs planSummary: COLLSCAN ntoreturn:0 ntoskip:0 nscanned:1 nscannedObjects:1 keyUpdates:0 numYields:0 locks(micros) r:62 nreturned:1 reslen:106 0ms
2020-11-26T00:39:43.268+0000 [conn6] command admin.$cmd command: replSetGetStatus { replSetGetStatus: 1.0, forShell: 1.0 } keyUpdates:0 numYields:0 reslen:300 0ms
2020-11-26T00:39:52.681+0000 [conn6] end connection 127.0.0.1:50592 (2 connections now open)
2020-11-26T00:42:28.934+0000 [clientcursormon] connections:2
您不应该混合使用配置文件，即
mongod --config /etc/mongod.conf
和命令行选项
mongod --replSet rs0 --bind_ip localhost
很可能在您的配置中，您没有在/etc/mongod.conf中设置
replication:
replSetName: <string>
因此，当您使用service mongodb start启动MongoDB时，您可能会有不同的配置。
请注意，检查服务文件(在我的Redhat中，位于/etc/systemd/system/mongod.service(，它甚至可能指向不同的.conf文件。