副本集是mongodb提供的一种高可用解决方案。相对于原来的主从复制，副本集能自动感知primary节点的下线，并提升其中一个Secondary作为Primary。
整个过程对业务透明，同时也大大降低了运维的成本。
架构图如下：
MongoDB副本集的角色
1. Primary
默认情况下，读写都是在Primary上操作的。
2. Secondary
通过oplog来重放Primary上的所有操作，拥有Primary节点数据的完整拷贝。
默认情况下，不可写，也不可读。
根据不同的需求，Secondary又可配置为如下形式：
1> Priority 0 Replica Set Members
优先级为0的节点，优先级为0的成员永远不会被选举为primary。
在mongoDB副本集中，允许给不同的节点设置不同的优先级。
优先级的取值范围为0-1000，可设置为浮点数，默认为1。
拥有最高优先级的成员会优先选举为primary。
譬如，在副本集中添加了一个优先级为2的成员node3:27020，而其它成员的优先级为1，只要node3:27020拥有最新的数据，那么当前的primary就会自动降
级，node3:27020将会被选举为新的primary节点，但如果node3:27020中的数据不够新，则当前primary节点保持不变，直到node3:27020的数据更新到最新。
2> Hidden Replica Set Members-隐藏节点
隐藏节点的优先级同样为0，同时对客户端不可见
使用rs.status()和rs.config()可以看到隐藏节点，但是对于db.isMaster()不可见。客户端连接到副本集时，会调用db.isMaster()命令来查看可用成员信息。
所以，隐藏节点不会受到客户端的读请求。
隐藏节点常用于执行特定的任务，譬如报表，备份。
3> Delayed Replica Set Members-延迟节点
延迟节点会比primary节点延迟指定的时间（通过slaveDelay参数来指定）
延迟节点必须是隐藏节点。
3. Arbiter
仲裁节点，只是用来投票，且投票的权重只能为1，不复制数据，也不能提升为primary。
仲裁节点常用于节点数量是偶数的副本集中。
建议：通常将Arbiter部署在业务服务器上，切忌将其部署在Primary节点或Secondary节点服务器上。
注：一个副本集最多有50个成员节点，7个投票节点。
MongoDB副本集的搭建
创建数据目录
# mkdir -p /data/27017
# mkdir -p /data/27018
# mkdir -p /data/27019
为了便于查看运行过程中的日志信息，为每个实例创建单独的日志文件
# mkdir -p /var/log/mongodb/
启动mongod实例
# mongod --replSet myapp --dbpath /data/27017 --port 27017 --logpath /var/log/mongodb/27017.log --fork
# mongod --replSet myapp --dbpath /data/27018 --port 27018 --logpath /var/log/mongodb/27018.log --fork
# mongod --replSet myapp --dbpath /data/27019 --port 27019 --logpath /var/log/mongodb/27019.log --fork
以27017端口实例为例，其日志输出信息如下：
--02T14::22.745+ I CONTROL [initandlisten] MongoDB starting : pid= port= dbpath=/data/ -bit host=node3
--02T14::22.745+ I CONTROL [initandlisten] db version v3.4.2
--02T14::22.745+ I CONTROL [initandlisten] git version: 3f76e40c105fc223b3e5aac3e20dcd026b83b38b
--02T14::22.745+ I CONTROL [initandlisten] OpenSSL version: OpenSSL 1.0.1e-fips Feb
--02T14::22.745+ I CONTROL [initandlisten] allocator: tcmalloc
--02T14::22.745+ I CONTROL [initandlisten] modules: none
--02T14::22.745+ I CONTROL [initandlisten] build environment:
--02T14::22.745+ I CONTROL [initandlisten] distmod: rhel62
--02T14::22.745+ I CONTROL [initandlisten] distarch: x86_64
--02T14::22.745+ I CONTROL [initandlisten] target_arch: x86_64
--02T14::22.745+ I CONTROL [initandlisten] options: { net: { port: }, processManagement: { fork: true }, replication: { replSet: "myapp" }, storage: { dbPath: "/data/27017" }, systemLog: { destination: "file", path: "/var/log/mongodb/27017.log" } }
--02T14::22.768+ I - [initandlisten] --02T14::22.768+ I STORAGE [initandlisten] ** WARNING: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine2017--02T14::22.768+ I STORAGE [initandlisten] ** See http://dochub.mongodb.org/core/prodnotes-filesystem
--02T14::22.769+ I STORAGE [initandlisten] wiredtiger_open config: create,cache_size=256M,session_max=,eviction=(threads_max=),config_base=false,statistics=(fast),log=(enabled=true,archive=true,path=journal,compressor=snappy),file_manager=(close_idle_time=),checkpoint=(wait=,log_size=2GB),statistics_log=(wait=),--02T14::24.450+ I CONTROL [initandlisten]
--02T14::24.482+ I CONTROL [initandlisten] ** WARNING: Access control is not enabled for the database.
--02T14::24.482+ I CONTROL [initandlisten] ** Read and write access to data and configuration is unrestricted.
--02T14::24.482+ I CONTROL [initandlisten] ** WARNING: You are running this process as the root user, which is not recommended.--02T14::24.482+ I CONTROL [initandlisten]
--02T14::24.516+ I FTDC [initandlisten] Initializing full-time diagnostic data capture with directory '/data/27017/diagnostic.data'--02T14::24.517+ I REPL [initandlisten] Did not find local voted for document at startup.
--02T14::24.517+ I REPL [initandlisten] Did not find local replica set configuration document at startup; NoMatchingDocument: Did not find replica set configuration document in local.system.replset
--02T14::24.519+ I NETWORK [thread1] waiting for connections on port
通过mongo连接副本集任一成员，在这里，连接27017端口实例
# mongo
初始化副本集
> rs.initiate()
{
"info2" : "no configuration specified. Using a default configuration for the set",
"me" : "node3:27017",
"ok" :
}
可通过rs.conf()查看当前副本集的配置信息，
myapp:PRIMARY> rs.conf()
{
"_id" : "myapp",
"version" : ,
"protocolVersion" : NumberLong(),
"members" : [
{
"_id" : ,
"host" : "node3:27017",
"arbiterOnly" : false,
"buildIndexes" : true,
"hidden" : false,
"priority" : ,
"tags" : { },
"slaveDelay" : NumberLong(),
"votes" :
}
],
"settings" : {
"chainingAllowed" : true,
"heartbeatIntervalMillis" : ,
"heartbeatTimeoutSecs" : ,
"electionTimeoutMillis" : ,
"catchUpTimeoutMillis" : ,
"getLastErrorModes" : { },
"getLastErrorDefaults" : {
"w" : ,
"wtimeout" :
},
"replicaSetId" : ObjectId("59082229517dd35bb9fd0d2a")
}
}
其中，settings中的选项解释如下：
chainingAllowed：是否允许级联复制
heartbeatIntervalMillis：心跳检测时间，默认是2s
heartbeatTimeoutSecs：心跳检测失效时间，默认为10s，即如果在10s内没有收到节点的心跳信息，则判断节点不可达（HostUnreachable），对primary和Secondary均适用。
日志输出信息如下：
# vim /var/log/mongodb/27017.log
--02T14::47.361+ I NETWORK [thread1] connection accepted from 127.0.0.1: # ( connection now open)
--02T14::47.361+ I NETWORK [conn1] received client metadata from 127.0.0.1: conn1: { application: { name: "MongoDB Shell" }, driver: { name: "MongoDB Internal Client", version: "3.4.2" }, os: { type: "Linux", name: "Red Hat Enterprise Linux Server release 6.7 (Santiago)", architecture: "x86_64", version: "Kernel 2.6.32-573.el6.x86_64" } }
--02T14::36.737+ I COMMAND [conn1] initiate : no configuration specified. Using a default configuration for the set
--02T14::36.737+ I COMMAND [conn1] created this configuration for initiation : { _id: "myapp", version: , members: [ { _id: , host: "node3:27017" } ] }
--02T14::36.900+ I REPL [conn1] replSetInitiate admin command received from client
--02T14::37.391+ I REPL [conn1] replSetInitiate config object with members parses ok
--02T14::37.410+ I REPL [conn1] ******
--02T14::37.410+ I REPL [conn1] creating replication oplog of size: 990MB...
--02T14::37.439+ I STORAGE [conn1] Starting WiredTigerRecordStoreThread local.oplog.rs
--02T14::37.440+ I STORAGE [conn1] The size storer reports that the oplog contains records totaling to bytes
--02T14::37.440+ I STORAGE [conn1] Scanning the oplog to determine where to place markers for truncation
--02T14::37.472+ I REPL [conn1] ******
--02T14::37.568+ I INDEX [conn1] build index on: admin.system.version properties: { v: , key: { version: }, name: "incompatible_with_version_32", ns: "admin.system.version" }
--02T14::37.568+ I INDEX [conn1] building index using bulk method; build may temporarily use up to megabytes of RAM
--02T14::37.581+ I INDEX [conn1] build index done. scanned total records. secs
--02T14::37.591+ I COMMAND [conn1] setting featureCompatibilityVersion to 3.4
--02T14::37.601+ I REPL [conn1] New replica set config in use: { _id: "myapp", version: , protocolVersion: , members: [ { _id: , host: "node3:27017", arbiterOnly: false, buildIndexes: true, hidden: false, priority: 1.0, tags: {}, slaveDelay: , votes: } ], settings: { chainingAllowed: true, heartbeatIntervalMillis: , heartbeatTimeoutSecs: , electionTimeoutMillis: , catchUpTimeoutMillis: , getLastErrorModes: {}, getLastErrorDefaults: { w: , wtimeout: }, replicaSetId: ObjectId('59082229517dd35bb9fd0d2a') } }
--02T14::37.601+ I REPL [conn1] This node is node3: in the config
--02T14::37.601+ I REPL [conn1] transition to STARTUP2
--02T14::37.601+ I REPL [conn1] Starting replication storage threads
--02T14::37.603+ I REPL [conn1] Starting replication fetcher thread
--02T14::37.617+ I REPL [conn1] Starting replication applier thread
--02T14::37.617+ I REPL [conn1] Starting replication reporter thread
--02T14::37.617+ I REPL [rsSync] transition to RECOVERING
--02T14::37.628+ I REPL [rsSync] transition to SECONDARY
--02T14::37.635+ I COMMAND [conn1] command local.replset.minvalid appName: "MongoDB Shell" command: replSetInitiate { v: , key: { version: }, ns: "admin.system.version", name: "incompatible_with_version_32" } numYields: reslen: locks:{ Global: { acquireCount: { r: , w: , W: }, acquireWaitCount: { W: }, timeAcquiringMicros: { W: } }, Database: { acquireCount: { r: , w: , W: } }, Collection: { acquireCount: { r: , w: } }, Metadata: { acquireCount: { w: } }, oplog: { acquireCount: { w: } } } protocol:op_command 941ms
--02T14::37.646+ I REPL [rsSync] conducting a dry run election to see if we could be elected
--02T14::37.646+ I REPL [ReplicationExecutor] dry election run succeeded, running for election
--02T14::37.675+ I REPL [ReplicationExecutor] election succeeded, assuming primary role in term
--02T14::37.675+ I REPL [ReplicationExecutor] transition to PRIMARY
--02T14::37.675+ I REPL [ReplicationExecutor] Could not access any nodes within timeout when checking for additional ops to apply before finishing transition to primary. Will move forward with becoming primary anyway.
--02T14::38.687+ I REPL [rsSync] transition to primary complete; database writes are now permitted
添加节点
myapp:PRIMARY> rs.add("node3:27018")
{ "ok" : }
27017端口实例的日志信息如下：
--02T15::44.737+ I COMMAND [conn1] command local.system.replset appName: "MongoDB Shell" command: count { count: "system.replset", query: {}, fields: {} } planSummary: COUNT keysExamined: docsExamined: numYields: reslen: locks:{ Global: { acquireCount: { r: } }, Database: { acquireCount: { r: } }, Collection: { acquireCount: { r: } } } protocol:op_command 135ms
--02T15::44.765+ I REPL [conn1] replSetReconfig admin command received from client
--02T15::44.808+ I REPL [conn1] replSetReconfig config object with members parses ok
--02T15::44.928+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T15::44.979+ I ASIO [NetworkInterfaceASIO-Replication-] Successfully connected to node3:
--02T15::44.994+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connections now open)
--02T15::45.007+ I NETWORK [conn3] received client metadata from 192.168.244.30: conn3: { driver: { name: "NetworkInterfaceASIO-Replication", version: "3.4.2" }, os: { type: "Linux", name: "Red Hat Enterprise Linux Server release 6.7 (Santiago)", architecture: "x86_64", version: "Kernel 2.6.32-573.el6.x86_64" } }
--02T15::45.009+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connections now open)
--02T15::45.010+ I - [conn4] end connection 192.168.244.30: ( connections now open)
--02T15::45.105+ I REPL [ReplicationExecutor] New replica set config in use: { _id: "myapp", version: , protocolVersion: , members: [ { _id: , host: "node3:27017", arbiterOnly: false, buildIndexes: true, hidden: false, priority: 1.0, tags: {}, slaveDelay: , votes: }, { _id: , host: "node3:27018", arbiterOnly: false, buildIndexes: true, hidden: false, priority: 1.0, tags: {}, slaveDelay: , votes: } ], settings: { chainingAllowed: true, heartbeatIntervalMillis: , heartbeatTimeoutSecs: , electionTimeoutMillis: , catchUpTimeoutMillis: , getLastErrorModes: {}, getLastErrorDefaults: { w: , wtimeout: }, replicaSetId: ObjectId('59082229517dd35bb9fd0d2a') } }
--02T15::45.105+ I REPL [ReplicationExecutor] This node is node3: in the config
--02T15::45.155+ I REPL [ReplicationExecutor] Member node3: is now in state STARTUP
--02T15::45.155+ I COMMAND [conn1] command local.system.replset appName: "MongoDB Shell" command: replSetReconfig { replSetReconfig: { _id: "myapp", version: , protocolVersion: , members: [ { _id: , host: "node3:27017", arbiterOnly: false, buildIndexes: true, hidden: false, priority: 1.0, tags: {}, slaveDelay: , votes: }, { _id: 1.0, host: "node3:27018" } ], settings: { chainingAllowed: true, heartbeatIntervalMillis: , heartbeatTimeoutSecs: , electionTimeoutMillis: , catchUpTimeoutMillis: , getLastErrorModes: {}, getLastErrorDefaults: { w: , wtimeout: }, replicaSetId: ObjectId('59082229517dd35bb9fd0d2a') } } } numYields: reslen: locks:{ Global: { acquireCount: { r: , w: , W: } }, Database: { acquireCount: { w: , W: } }, Metadata: { acquireCount: { w: } }, oplog: { acquireCount: { w: } } } protocol:op_command 403ms
--02T15::47.010+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connections now open)
--02T15::47.011+ I - [conn5] end connection 192.168.244.30: ( connections now open)
--02T15::47.940+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connections now open)
--02T15::47.941+ I NETWORK [conn6] received client metadata from 192.168.244.30: conn6: { driver: { name: "NetworkInterfaceASIO-RS", version: "3.4.2" }, os: { type: "Linux", name: "Red Hat Enterprise Linux Server release 6.7 (Santiago)", architecture: "x86_64", version: "Kernel 2.6.32-573.el6.x86_64" } }
--02T15::48.010+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connections now open)
--02T15::48.011+ I NETWORK [conn7] received client metadata from 192.168.244.30: conn7: { driver: { name: "NetworkInterfaceASIO-RS", version: "3.4.2" }, os: { type: "Linux", name: "Red Hat Enterprise Linux Server release 6.7 (Santiago)", architecture: "x86_64", version: "Kernel 2.6.32-573.el6.x86_64" } }
--02T15::49.159+ I REPL [ReplicationExecutor] Member node3: is now in state SECONDARY
--02T15::49.160+ I - [conn6] end connection 192.168.244.30: ( connections now open)
--02T15::03.401+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connections now open)
--02T15::03.403+ I NETWORK [conn8] received client metadata from 192.168.244.30: conn8: { driver: { name: "NetworkInterfaceASIO-RS", version: "3.4.2" }, os: { type: "Linux", name: "Red Hat Enterprise Linux Server release 6.7 (Santiago)", architecture: "x86_64", version: "Kernel 2.6.32-573.el6.x86_64" } }
27018端口实例的日志信息如下：
--02T15::44.796+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connection now open)
--02T15::44.922+ I - [conn2] end connection 192.168.244.30: ( connection now open)
--02T15::44.965+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connection now open)
--02T15::44.978+ I NETWORK [conn3] received client metadata from 192.168.244.30: conn3: { driver: { name: "NetworkInterfaceASIO-Replication", version: "3.4.2" }, os: { type: "Linux", name: "Red Hat Enterprise Linux Server release 6.7 (Santiago)", architecture: "x86_64", version: "Kernel 2.6.32-573.el6.x86_64" } }
--02T15::44.991+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T15::45.008+ I ASIO [NetworkInterfaceASIO-Replication-] Successfully connected to node3:
--02T15::47.101+ I REPL [replExecDBWorker-] Starting replication storage threads
--02T15::47.174+ I REPL [replication-] Starting initial sync (attempt of )
--02T15::47.174+ I REPL [ReplicationExecutor] New replica set config in use: { _id: "myapp", version: , protocolVersion: , members: [ { _id: , host: "node3:27017", arbiterOnly: false, buildIndexes: true, hidden: false, priority: 1.0, tags: {}, slaveDelay: , votes: }, { _id: , host: "node3:27018", arbiterOnly: false, buildIndexes: true, hidden: false, priority: 1.0, tags: {}, slaveDelay: , votes: } ], settings: { chainingAllowed: true, heartbeatIntervalMillis: , heartbeatTimeoutSecs: , electionTimeoutMillis: , catchUpTimeoutMillis: , getLastErrorModes: {}, getLastErrorDefaults: { w: , wtimeout: }, replicaSetId: ObjectId('59082229517dd35bb9fd0d2a') } }
--02T15::47.174+ I REPL [ReplicationExecutor] This node is node3: in the config
--02T15::47.174+ I REPL [ReplicationExecutor] transition to STARTUP2
--02T15::47.175+ I REPL [ReplicationExecutor] Member node3: is now in state PRIMARY
--02T15::47.217+ I REPL [replication-] sync source candidate: node3:
--02T15::47.217+ I STORAGE [replication-] dropAllDatabasesExceptLocal
--02T15::47.217+ I REPL [replication-] ******
--02T15::47.217+ I REPL [replication-] creating replication oplog of size: 990MB...
--02T15::47.232+ I STORAGE [replication-] Starting WiredTigerRecordStoreThread local.oplog.rs
--02T15::47.232+ I STORAGE [replication-] The size storer reports that the oplog contains records totaling to bytes
--02T15::47.232+ I STORAGE [replication-] Scanning the oplog to determine where to place markers for truncation
--02T15::47.938+ I REPL [replication-] ******
--02T15::47.939+ I ASIO [NetworkInterfaceASIO-RS-] Connecting to node3:
--02T15::47.941+ I ASIO [NetworkInterfaceASIO-RS-] Successfully connected to node3:
--02T15::48.010+ I ASIO [NetworkInterfaceASIO-RS-] Connecting to node3:
--02T15::48.011+ I ASIO [NetworkInterfaceASIO-RS-] Successfully connected to node3:
--02T15::48.046+ I REPL [replication-] CollectionCloner::start called, on ns:admin.system.version
--02T15::48.150+ I INDEX [InitialSyncInserters-admin.system.version0] build index on: admin.system.version properties: { v: , key: { version: }, name: "incompatible_with_version_32", ns: "admin.system.version" }
--02T15::48.150+ I INDEX [InitialSyncInserters-admin.system.version0] building index using bulk method; build may temporarily use up to megabytes of RAM
--02T15::48.154+ I INDEX [InitialSyncInserters-admin.system.version0] build index on: admin.system.version properties: { v: , key: { _id: }, name: "_id_", ns: "admin.system.version" }
--02T15::48.155+ I INDEX [InitialSyncInserters-admin.system.version0] building index using bulk method; build may temporarily use up to megabytes of RAM
--02T15::48.177+ I COMMAND [InitialSyncInserters-admin.system.version0] setting featureCompatibilityVersion to 3.4
--02T15::48.221+ I REPL [replication-] CollectionCloner::start called, on ns:test.blog
--02T15::48.264+ I INDEX [InitialSyncInserters-test.blog0] build index on: test.blog properties: { v: , key: { _id: }, name: "_id_", ns: "test.blog" }
--02T15::48.264+ I INDEX [InitialSyncInserters-test.blog0] building index using bulk method; build may temporarily use up to megabytes of RAM
--02T15::48.271+ I REPL [replication-] No need to apply operations. (currently at { : Timestamp | })
--02T15::48.271+ I REPL [replication-] Finished fetching oplog during initial sync: CallbackCanceled: Callback canceled. Last fetched optime and hash: { ts: Timestamp |, t: }[]
--02T15::48.271+ I REPL [replication-] Initial sync attempt finishing up.
--02T15::48.271+ I REPL [replication-] Initial Sync Attempt Statistics: { failedInitialSyncAttempts: , maxFailedInitialSyncAttempts: , initialSyncStart: new Date(), initialSyncAttempts: [], fetchedMissingDocs: , appliedOps: , initialSyncOplogStart: Timestamp |, initialSyncOplogEnd: Timestamp |, databases: { databasesCloned: , admin: { collections: , clonedCollections: , start: new Date(), end: new Date(), elapsedMillis: , admin.system.version: { documentsToCopy: , documentsCopied: , indexes: , fetchedBatches: , start: new Date(), end: new Date(), elapsedMillis: } }, test: { collections: , clonedCollections: , start: new Date(), end: new Date(), elapsedMillis: , test.blog: { documentsToCopy: , documentsCopied: , indexes: , fetchedBatches: , start: new Date(), end: new Date(), elapsedMillis: } } } }
--02T15::48.352+ I REPL [replication-] initial sync done; took 1s.
--02T15::48.352+ I REPL [replication-] Starting replication fetcher thread
--02T15::48.352+ I REPL [replication-] Starting replication applier thread
--02T15::48.352+ I REPL [replication-] Starting replication reporter thread
--02T15::48.352+ I REPL [rsSync] transition to RECOVERING
--02T15::48.366+ I REPL [rsBackgroundSync] could not find member to sync from
--02T15::48.367+ I REPL [rsSync] transition to SECONDARY
--02T15::03.392+ I REPL [rsBackgroundSync] sync source candidate: node3:
--02T15::03.396+ I ASIO [NetworkInterfaceASIO-RS-] Connecting to node3:
--02T15::03.404+ I ASIO [NetworkInterfaceASIO-RS-] Successfully connected to node3:
添加仲裁节点
myapp:PRIMARY> rs.addArb("node3:27019")
{ "ok" : }
27017端口实例的日志信息如下：
--02T16::59.098+ I REPL [conn1] replSetReconfig admin command received from client
--02T16::59.116+ I REPL [conn1] replSetReconfig config object with members parses ok
--02T16::59.116+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T16::59.123+ I REPL [ReplicationExecutor] New replica set config in use: { _id: "myapp", version: , protocolVersion: , members: [ { _id: , host: "node3:27017", arbiterOnly: false, buildIndexes: true, hidden: false, priority: 1.0, tags: {}, slaveDelay: , votes: }, { _id: , host: "node3:27018", arbiterOnly: false, buildIndexes: true, hidden: false, priority: 1.0, tags: {}, slaveDelay: , votes: }, { _id: , host: "node3:27019", arbiterOnly: true, buildIndexes: true, hidden: false, priority: 1.0, tags: {}, slaveDelay: , votes: } ], settings: { chainingAllowed: true, heartbeatIntervalMillis: , heartbeatTimeoutSecs: , electionTimeoutMillis: , catchUpTimeoutMillis: , getLastErrorModes: {}, getLastErrorDefaults: { w: , wtimeout: }, replicaSetId: ObjectId('59082229517dd35bb9fd0d2a') } }
--02T16::59.123+ I REPL [ReplicationExecutor] This node is node3: in the config
--02T16::59.124+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T16::59.124+ I ASIO [NetworkInterfaceASIO-Replication-] Successfully connected to node3:
--02T16::59.125+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connections now open)
--02T16::59.127+ I - [conn9] end connection 192.168.244.30: ( connections now open)
--02T16::59.131+ I REPL [ReplicationExecutor] Member node3: is now in state STARTUP
--02T16::59.137+ I ASIO [NetworkInterfaceASIO-Replication-] Successfully connected to node3:
--02T16::59.223+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connections now open)
--02T16::59.225+ I NETWORK [conn10] received client metadata from 192.168.244.30: conn10: { driver: { name: "NetworkInterfaceASIO-Replication", version: "3.4.2" }, os: { type: "Linux", name: "Red Hat Enterprise Linux Server release 6.7 (Santiago)", architecture: "x86_64", version: "Kernel 2.6.32-573.el6.x86_64" } }
--02T16::59.231+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connections now open)
--02T16::59.232+ I - [conn11] end connection 192.168.244.30: ( connections now open)
--02T16::01.132+ I REPL [ReplicationExecutor] Member node3: is now in state ARBITER
27019端口实例的日志信息如下：
--02T16::59.115+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connection now open)
--02T16::59.117+ I - [conn1] end connection 192.168.244.30: ( connection now open)
--02T16::59.117+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connection now open)
--02T16::59.122+ I NETWORK [conn2] received client metadata from 192.168.244.30: conn2: { driver: { name: "NetworkInterfaceASIO-Replication", version: "3.4.2" }, os: { type: "Linux", name: "Red Hat Enterprise Linux Server release 6.7 (Santiago)", architecture: "x86_64", version: "Kernel 2.6.32-573.el6.x86_64" } }
--02T16::59.125+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connections now open)
--02T16::59.127+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connections now open)
--02T16::59.128+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T16::59.135+ I - [conn4] end connection 192.168.244.30: ( connections now open)
--02T16::59.136+ I NETWORK [conn3] received client metadata from 192.168.244.30: conn3: { driver: { name: "NetworkInterfaceASIO-Replication", version: "3.4.2" }, os: { type: "Linux", name: "Red Hat Enterprise Linux Server release 6.7 (Santiago)", architecture: "x86_64", version: "Kernel 2.6.32-573.el6.x86_64" } }
--02T16::59.214+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connections now open)
--02T16::59.216+ I NETWORK [conn5] received client metadata from 192.168.244.30: conn5: { driver: { name: "NetworkInterfaceASIO-Replication", version: "3.4.2" }, os: { type: "Linux", name: "Red Hat Enterprise Linux Server release 6.7 (Santiago)", architecture: "x86_64", version: "Kernel 2.6.32-573.el6.x86_64" } }
--02T16::59.219+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T16::59.227+ I ASIO [NetworkInterfaceASIO-Replication-] Successfully connected to node3:
--02T16::59.227+ I ASIO [NetworkInterfaceASIO-Replication-] Successfully connected to node3:
--02T16::59.295+ I REPL [ReplicationExecutor] New replica set config in use: { _id: "myapp", version: , protocolVersion: , members: [ { _id: , host: "node3:27017", arbiterOnly: false, buildIndexes: true, hidden: false, priority: 1.0, tags: {}, slaveDelay: , votes: }, { _id: , host: "node3:27018", arbiterOnly: false, buildIndexes: true, hidden: false, priority: 1.0, tags: {}, slaveDelay: , votes: }, { _id: , host: "node3:27019", arbiterOnly: true, buildIndexes: true, hidden: false, priority: 1.0, tags: {}, slaveDelay: , votes: } ], settings: { chainingAllowed: true, heartbeatIntervalMillis: , heartbeatTimeoutSecs: , electionTimeoutMillis: , catchUpTimeoutMillis: , getLastErrorModes: {}, getLastErrorDefaults: { w: , wtimeout: }, replicaSetId: ObjectId('59082229517dd35bb9fd0d2a') } }
--02T16::59.295+ I REPL [ReplicationExecutor] This node is node3: in the config
--02T16::59.295+ I REPL [ReplicationExecutor] transition to ARBITER
--02T16::59.297+ I REPL [ReplicationExecutor] Member node3: is now in state PRIMARY
--02T16::59.297+ I REPL [ReplicationExecutor] Member node3: is now in state SECONDARY
--02T16::59.132+ I - [conn2] end connection 192.168.244.30: ( connections now open)
检查复制集的状态
myapp:PRIMARY> rs.status()
{
"set" : "myapp",
"date" : ISODate("2017-05-02T08:10:59.174Z"),
"myState" : ,
"term" : NumberLong(),
"heartbeatIntervalMillis" : NumberLong(),
"optimes" : {
"lastCommittedOpTime" : {
"ts" : Timestamp(, ),
"t" : NumberLong()
},
"appliedOpTime" : {
"ts" : Timestamp(, ),
"t" : NumberLong()
},
"durableOpTime" : {
"ts" : Timestamp(, ),
"t" : NumberLong()
}
},
"members" : [
{
"_id" : ,
"name" : "node3:27017",
"health" : ,
"state" : ,
"stateStr" : "PRIMARY",
"uptime" : ,
"optime" : {
"ts" : Timestamp(, ),
"t" : NumberLong()
},
"optimeDate" : ISODate("2017-05-02T08:10:49Z"),
"electionTime" : Timestamp(, ),
"electionDate" : ISODate("2017-05-02T06:07:37Z"),
"configVersion" : ,
"self" : true
},
{
"_id" : ,
"name" : "node3:27018",
"health" : ,
"state" : ,
"stateStr" : "SECONDARY",
"uptime" : ,
"optime" : {
"ts" : Timestamp(, ),
"t" : NumberLong()
},
"optimeDurable" : {
"ts" : Timestamp(, ),
"t" : NumberLong()
},
"optimeDate" : ISODate("2017-05-02T08:10:49Z"),
"optimeDurableDate" : ISODate("2017-05-02T08:10:49Z"),
"lastHeartbeat" : ISODate("2017-05-02T08:10:57.606Z"),
"lastHeartbeatRecv" : ISODate("2017-05-02T08:10:58.224Z"),
"pingMs" : NumberLong(),
"syncingTo" : "node3:27017",
"configVersion" :
},
{
"_id" : ,
"name" : "node3:27019",
"health" : ,
"state" : ,
"stateStr" : "ARBITER",
"uptime" : ,
"lastHeartbeat" : ISODate("2017-05-02T08:10:57.607Z"),
"lastHeartbeatRecv" : ISODate("2017-05-02T08:10:54.391Z"),
"pingMs" : NumberLong(),
"configVersion" :
}
],
"ok" :
}
副本集也可通过配置文件的方式进行创建
> cfg={
... "_id":"myapp",
... "members":[
... {"_id":,"host":"node3:27017"},
... {"_id":,"host":"node3:27018"},
... {"_id":,"host":"node3:27019","arbiterOnly" : true}
... ]}
> rs.initiate(cfg)
验证副本集的可用性
在primary中创建一个集合，并插入一个文档进行测试
# mongo
myapp:PRIMARY> show dbs;
admin .000GB
local .000GB
myapp:PRIMARY> use test
switched to db test
myapp:PRIMARY> db.blog.insert({"title":"My Blog Post"})
WriteResult({ "nInserted" : })
myapp:PRIMARY> db.blog.find();
{ "_id" : ObjectId("59082731008c534e0763e90a"), "title" : "My Blog Post" }
myapp:PRIMARY> quit()
在secondary中进行验证
# mongo --port
myapp:SECONDARY> use test
switched to db test
myapp:SECONDARY> db.blog.find()
Error: error: {
"ok" : ,
"errmsg" : "not master and slaveOk=false",
"code" : ,
"codeName" : "NotMasterNoSlaveOk"
}
myapp:SECONDARY> rs.slaveOk()
myapp:SECONDARY> db.blog.find()
{ "_id" : ObjectId("59082731008c534e0763e90a"), "title" : "My Blog Post" }
myapp:SECONDARY> quit()
因仲裁节点实际上并不存储任何数据，所以无法通过连接仲裁节点查看刚刚插入的文档
# mongo --port
myapp:ARBITER> use test
switched to db test
myapp:ARBITER> db.blog.find();
Error: error: {
"ok" : ,
"errmsg" : "not master and slaveOk=false",
"code" : ,
"codeName" : "NotMasterNoSlaveOk"
}
myapp:ARBITER> rs.slaveOk()
myapp:ARBITER> db.blog.find()
Error: error: {
"ok" : ,
"errmsg" : "node is not in primary or recovering state",
"code" : ,
"codeName" : "NotMasterOrSecondary"
}
myapp:ARBITER> quit()
模拟primary宕掉后，副本集的自动切换
# ps -ef |grep mongodb
root : ? :: mongod --replSet myapp --dbpath /data/ --port --logpath /var/log/mongodb
/.log --forkroot : ? :: mongod --replSet myapp --dbpath /data/ --port --logpath /var/log/mongodb
/.log --forkroot : ? :: mongod --replSet myapp --dbpath /data/ --port --logpath /var/log/mongodb
/.log --forkroot : pts/ :: vim /var/log/mongodb/.log
root : pts/ :: tailf /var/log/mongodb/.log
root : pts/ :: tailf /var/log/mongodb/.log
root : pts/ :: grep mongodb
# kill -
检查复制集的状态
在这里，连接27018端口实例
# mongo --port 27018
myapp:PRIMARY> db.isMaster()
{
"hosts" : [
"node3:27017",
"node3:27018"
],
"arbiters" : [
"node3:27019"
],
"setName" : "myapp",
"setVersion" : ,
"ismaster" : true,
"secondary" : false,
"primary" : "node3:27018",
"me" : "node3:27018",
"electionId" : ObjectId("7fffffff0000000000000002"),
"lastWrite" : {
"opTime" : {
"ts" : Timestamp(, ),
"t" : NumberLong()
},
"lastWriteDate" : ISODate("2017-05-02T09:19:02Z")
},
"maxBsonObjectSize" : ,
"maxMessageSizeBytes" : ,
"maxWriteBatchSize" : ,
"localTime" : ISODate("2017-05-02T09:19:04.870Z"),
"maxWireVersion" : ,
"minWireVersion" : ,
"readOnly" : false,
"ok" :
}
可见，primary已经切换到27018端口实例上了。
对应的，27018端口实例的日志输出信息如下：
--02T17::51.853+ I - [conn3] end connection 192.168.244.30: ( connections now open)
--02T17::51.853+ I REPL [replication-] Restarting oplog query due to error: HostUnreachable: End of file. Last fetched optime (with hash): { ts: Timestamp |, t: }[-]. Restarts remaining:
--02T17::51.878+ I ASIO [replication-] dropping unhealthy pooled connection to node3:
--02T17::51.878+ I ASIO [replication-] after drop, pool was empty, going to spawn some connections
--02T17::51.879+ I REPL [replication-] Scheduled new oplog query Fetcher source: node3: database: local query: { find: "oplog.rs", filter: { ts: { $gte: Timestamp | } }, tailable: true, oplogReplay: true, awaitData: true, maxTimeMS: , term: } query metadata: { $replData: , $ssm: { $secondaryOk: true } } active: timeout: 10000ms shutting down?: first: firstCommandScheduler: RemoteCommandRetryScheduler request: RemoteCommand -- target:node3: db:local cmd:{ find: "oplog.rs", filter: { ts: { $gte: Timestamp | } }, tailable: true, oplogReplay: true, awaitData: true, maxTimeMS: , term: } active: callbackHandle.valid: callbackHandle.cancelled: attempt: retryPolicy: RetryPolicyImpl maxAttempts: maxTimeMillis: -1ms
--02T17::51.879+ I ASIO [NetworkInterfaceASIO-RS-] Connecting to node3:
--02T17::51.879+ I ASIO [NetworkInterfaceASIO-RS-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::51.880+ I REPL [replication-] Restarting oplog query due to error: HostUnreachable: Connection refused. Last fetched optime (with hash): { ts: Timestamp |, t: }[-]. Restarts remaining:
--02T17::51.880+ I REPL [replication-] Scheduled new oplog query Fetcher source: node3: database: local query: { find: "oplog.rs", filter: { ts: { $gte: Timestamp | } }, tailable: true, oplogReplay: true, awaitData: true, maxTimeMS: , term: } query metadata: { $replData: , $ssm: { $secondaryOk: true } } active: timeout: 10000ms shutting down?: first: firstCommandScheduler: RemoteCommandRetryScheduler request: RemoteCommand -- target:node3: db:local cmd:{ find: "oplog.rs", filter: { ts: { $gte: Timestamp | } }, tailable: true, oplogReplay: true, awaitData: true, maxTimeMS: , term: } active: callbackHandle.valid: callbackHandle.cancelled: attempt: retryPolicy: RetryPolicyImpl maxAttempts: maxTimeMillis: -1ms
--02T17::51.880+ I ASIO [NetworkInterfaceASIO-RS-] Connecting to node3:
--02T17::51.880+ I ASIO [NetworkInterfaceASIO-RS-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::51.880+ I REPL [replication-] Restarting oplog query due to error: HostUnreachable: Connection refused. Last fetched optime (with hash): { ts: Timestamp |, t: }[-]. Restarts remaining:
--02T17::51.880+ I REPL [replication-] Scheduled new oplog query Fetcher source: node3: database: local query: { find: "oplog.rs", filter: { ts: { $gte: Timestamp | } }, tailable: true, oplogReplay: true, awaitData: true, maxTimeMS: , term: } query metadata: { $replData: , $ssm: { $secondaryOk: true } } active: timeout: 10000ms shutting down?: first: firstCommandScheduler: RemoteCommandRetryScheduler request: RemoteCommand -- target:node3: db:local cmd:{ find: "oplog.rs", filter: { ts: { $gte: Timestamp | } }, tailable: true, oplogReplay: true, awaitData: true, maxTimeMS: , term: } active: callbackHandle.valid: callbackHandle.cancelled: attempt: retryPolicy: RetryPolicyImpl maxAttempts: maxTimeMillis: -1ms
--02T17::51.880+ I ASIO [NetworkInterfaceASIO-RS-] Connecting to node3:
--02T17::51.883+ I ASIO [NetworkInterfaceASIO-RS-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::51.884+ I REPL [replication-] Error returned from oplog query (no more query restarts left): HostUnreachable: Connection refused
--02T17::51.884+ W REPL [rsBackgroundSync] Fetcher stopped querying remote oplog with error: HostUnreachable: Connection refused
--02T17::51.884+ I REPL [rsBackgroundSync] could not find member to sync from
--02T17::51.884+ I ASIO [ReplicationExecutor] dropping unhealthy pooled connection to node3:
--02T17::51.884+ I ASIO [ReplicationExecutor] after drop, pool was empty, going to spawn some connections
--02T17::51.884+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::51.885+ I ASIO [NetworkInterfaceASIO-Replication-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::51.885+ I REPL [ReplicationExecutor] Error in heartbeat request to node3:; HostUnreachable: Connection refused
--02T17::51.885+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::51.885+ I ASIO [NetworkInterfaceASIO-Replication-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::51.885+ I REPL [ReplicationExecutor] Error in heartbeat request to node3:; HostUnreachable: Connection refused
--02T17::51.885+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::51.885+ I ASIO [NetworkInterfaceASIO-Replication-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::51.886+ I REPL [ReplicationExecutor] Error in heartbeat request to node3:; HostUnreachable: Connection refused
--02T17::54.837+ I REPL [SyncSourceFeedback] SyncSourceFeedback error sending update to node3:: InvalidSyncSource: Sync source was cleared. Was node3:
--02T17::56.886+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::56.886+ I ASIO [NetworkInterfaceASIO-Replication-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::56.886+ I REPL [ReplicationExecutor] Error in heartbeat request to node3:; HostUnreachable: Connection refused
--02T17::56.886+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::56.887+ I ASIO [NetworkInterfaceASIO-Replication-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::56.887+ I REPL [ReplicationExecutor] Error in heartbeat request to node3:; HostUnreachable: Connection refused
--02T17::56.887+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::56.887+ I ASIO [NetworkInterfaceASIO-Replication-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::56.887+ I REPL [ReplicationExecutor] Error in heartbeat request to node3:; HostUnreachable: Connection refused
--02T17::01.560+ I REPL [ReplicationExecutor] Starting an election, since we've seen no PRIMARY in the past 10000ms
--02T17::01.605+ I REPL [ReplicationExecutor] conducting a dry run election to see if we could be elected
--02T17::01.616+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::01.626+ I ASIO [NetworkInterfaceASIO-Replication-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::01.630+ I REPL [ReplicationExecutor] VoteRequester(term dry run) failed to receive response from node3:: HostUnreachable: Connection refused
--02T17::01.637+ I REPL [ReplicationExecutor] VoteRequester(term dry run) received a yes vote from node3:; response message: { term: , voteGranted: true, reason: "", ok: 1.0 }
--02T17::01.638+ I REPL [ReplicationExecutor] dry election run succeeded, running for election
--02T17::01.670+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::01.670+ I ASIO [NetworkInterfaceASIO-Replication-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::01.672+ I REPL [ReplicationExecutor] VoteRequester(term ) failed to receive response from node3:: HostUnreachable: Connection refused
--02T17::01.689+ I REPL [ReplicationExecutor] VoteRequester(term ) received a yes vote from node3:; response message: { term: , voteGranted: true, reason: "", ok: 1.0 }
--02T17::01.689+ I REPL [ReplicationExecutor] election succeeded, assuming primary role in term
--02T17::01.689+ I REPL [ReplicationExecutor] transition to PRIMARY
--02T17::01.691+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::01.692+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::01.692+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::01.693+ I ASIO [NetworkInterfaceASIO-Replication-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::01.693+ I REPL [ReplicationExecutor] My optime is most up-to-date, skipping catch-up and completing transition to primary.
--02T17::01.693+ I REPL [ReplicationExecutor] Error in heartbeat request to node3:; HostUnreachable: Connection refused
--02T17::01.693+ I ASIO [NetworkInterfaceASIO-Replication-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::01.693+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::01.694+ I ASIO [NetworkInterfaceASIO-Replication-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::01.694+ I REPL [ReplicationExecutor] Error in heartbeat request to node3:; HostUnreachable: Connection refused
--02T17::01.694+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::01.694+ I ASIO [NetworkInterfaceASIO-Replication-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::01.694+ I REPL [ReplicationExecutor] Error in heartbeat request to node3:; HostUnreachable: Connection refused
--02T17::01.694+ I ASIO [NetworkInterfaceASIO-Replication-] Successfully connected to node3:
--02T17::02.094+ I REPL [rsSync] transition to primary complete; database writes are now permitted
从日志输出中可以看出，
在第一次探测到primary不可用时，mongodb会剔除掉不健康连接（dropping unhealthy pooled connection to node3:27017），然后继续探测，直到到达10s（heartbeatTimeoutSecs）的限制，此时进行primary的自动切换。
--02T17::01.560+ I REPL [ReplicationExecutor] Starting an election, since we've seen no PRIMARY in the past 10000ms
--02T17::01.605+ I REPL [ReplicationExecutor] conducting a dry run election to see if we could be elected
--02T17::01.616+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::01.626+ I ASIO [NetworkInterfaceASIO-Replication-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::01.630+ I REPL [ReplicationExecutor] VoteRequester(term dry run) failed to receive response from node3:: HostUnreachable: Connection refused
--02T17::01.637+ I REPL [ReplicationExecutor] VoteRequester(term dry run) received a yes vote from node3:; response message: { term: , voteGranted: true, reason: "", ok: 1.0 }
--02T17::01.638+ I REPL [ReplicationExecutor] dry election run succeeded, running for election
--02T17::01.670+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::01.670+ I ASIO [NetworkInterfaceASIO-Replication-] Failed to connect to node3: - HostUnreachable: Connection refused
--02T17::01.672+ I REPL [ReplicationExecutor] VoteRequester(term ) failed to receive response from node3:: HostUnreachable: Connection refused
--02T17::01.689+ I REPL [ReplicationExecutor] VoteRequester(term ) received a yes vote from node3:; response message: { term: , voteGranted: true, reason: "", ok: 1.0 }
--02T17::01.689+ I REPL [ReplicationExecutor] election succeeded, assuming primary role in term
--02T17::01.689+ I REPL [ReplicationExecutor] transition to PRIMARY
实际上，在27017端口实例宕掉的过程中，其它两个节点均会继续针对27017端口实例进行心跳检测
--02T17::08.384+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::08.384+ I ASIO [NetworkInterfaceASIO-Replication-] Failed to connect to node3: - HostUnreachable: Conn
ection refused
2017--02T17::08.384+ I REPL [ReplicationExecutor] Error in heartbeat request to node3:; HostUnreachable: Connection
refused
当27017端口实例重新上线时，会自动以Secondary角色加入到副本集中
27017端口实例启动并重新加入副本集的日志信息输出如下：
--02T17::10.616+ I CONTROL [initandlisten] MongoDB starting : pid= port= dbpath=/data/ -bit host=node3
--02T17::10.616+ I CONTROL [initandlisten] db version v3.4.2
--02T17::10.616+ I CONTROL [initandlisten] git version: 3f76e40c105fc223b3e5aac3e20dcd026b83b38b
--02T17::10.616+ I CONTROL [initandlisten] OpenSSL version: OpenSSL 1.0.1e-fips Feb
--02T17::10.616+ I CONTROL [initandlisten] allocator: tcmalloc
--02T17::10.616+ I CONTROL [initandlisten] modules: none
--02T17::10.616+ I CONTROL [initandlisten] build environment:
--02T17::10.616+ I CONTROL [initandlisten] distmod: rhel62
--02T17::10.616+ I CONTROL [initandlisten] distarch: x86_64
--02T17::10.616+ I CONTROL [initandlisten] target_arch: x86_64
--02T17::10.616+ I CONTROL [initandlisten] options: { net: { port: }, processManagement: { fork: true }, replication: { replSet: "myapp" }, storage: { dbPath: "/data/27017" }, systemLog: { destination: "file", path: "/var/log/mongodb/27017.log" } }
--02T17::10.616+ W - [initandlisten] Detected unclean shutdown - /data//mongod.lock is not empty.
--02T17::10.645+ I - [initandlisten] Detected data files in /data/ created by the 'wiredTiger' storage engine, so setting the active storage engine to 'wiredTiger'.
--02T17::10.645+ W STORAGE [initandlisten] Recovering data from the last clean checkpoint.
--02T17::10.645+ I STORAGE [initandlisten]
--02T17::10.645+ I STORAGE [initandlisten] ** WARNING: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine
--02T17::10.645+ I STORAGE [initandlisten] ** See http://dochub.mongodb.org/core/prodnotes-filesystem
--02T17::10.645+ I STORAGE [initandlisten] wiredtiger_open config: create,cache_size=256M,session_max=,eviction=(threads_max=),config_base=false,statistics=(fast),log=(enabled=true,archive=true,path=journal,compressor=snappy),file_manager=(close_idle_time=),checkpoint=(wait=,log_size=2GB),statistics_log=(wait=),
--02T17::11.402+ I STORAGE [initandlisten] Starting WiredTigerRecordStoreThread local.oplog.rs
--02T17::11.436+ I STORAGE [initandlisten] The size storer reports that the oplog contains records totaling to bytes
--02T17::11.436+ I STORAGE [initandlisten] Scanning the oplog to determine where to place markers for truncation
--02T17::11.502+ I CONTROL [initandlisten]
--02T17::11.502+ I CONTROL [initandlisten] ** WARNING: Access control is not enabled for the database.
--02T17::11.502+ I CONTROL [initandlisten] ** Read and write access to data and configuration is unrestricted.
--02T17::11.502+ I CONTROL [initandlisten] ** WARNING: You are running this process as the root user, which is not recommended.
--02T17::11.502+ I CONTROL [initandlisten]
--02T17::11.675+ I FTDC [initandlisten] Initializing full-time diagnostic data capture with directory '/data/27017/diagnostic.data'
--02T17::11.744+ I NETWORK [thread1] waiting for connections on port
--02T17::11.797+ I REPL [replExecDBWorker-] New replica set config in use: { _id: "myapp", version: , protocolVersion: , members: [ { _id: , host: "node3:27017", arbiterOnly: false, buildIndexes: true, hidden: false, priority: 1.0, tags: {}, slaveDelay: , votes: }, { _id: , host: "node3:27018", arbiterOnly: false, buildIndexes: true, hidden: false, priority: 1.0, tags: {}, slaveDelay: , votes: }, { _id: , host: "node3:27019", arbiterOnly: true, buildIndexes: true, hidden: false, priority: 1.0, tags: {}, slaveDelay: , votes: } ], settings: { chainingAllowed: true, heartbeatIntervalMillis: , heartbeatTimeoutSecs: , electionTimeoutMillis: , catchUpTimeoutMillis: , getLastErrorModes: {}, getLastErrorDefaults: { w: , wtimeout: }, replicaSetId: ObjectId('59082229517dd35bb9fd0d2a') } }
--02T17::11.797+ I REPL [replExecDBWorker-] This node is node3: in the config
--02T17::11.797+ I REPL [replExecDBWorker-] transition to STARTUP2
--02T17::11.797+ I REPL [replExecDBWorker-] Starting replication storage threads
--02T17::11.798+ I REPL [replExecDBWorker-] Starting replication fetcher thread
--02T17::11.798+ I REPL [replExecDBWorker-] Starting replication applier thread
--02T17::11.798+ I REPL [replExecDBWorker-] Starting replication reporter thread
--02T17::11.799+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::11.799+ I ASIO [NetworkInterfaceASIO-Replication-] Connecting to node3:
--02T17::11.799+ I REPL [rsSync] transition to RECOVERING
--02T17::11.801+ I REPL [rsSync] transition to SECONDARY
--02T17::11.801+ I ASIO [NetworkInterfaceASIO-Replication-] Successfully connected to node3:
--02T17::11.801+ I ASIO [NetworkInterfaceASIO-Replication-] Successfully connected to node3:
--02T17::11.802+ I REPL [ReplicationExecutor] Member node3: is now in state ARBITER
--02T17::11.803+ I REPL [ReplicationExecutor] Member node3: is now in state PRIMARY
--02T17::12.116+ I FTDC [ftdc] Unclean full-time diagnostic data capture shutdown detected, found interim file, some metrics may have been lost. OK
--02T17::12.388+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connection now open)
--02T17::12.390+ I NETWORK [conn1] received client metadata from 192.168.244.30: conn1: { driver: { name: "NetworkInterfaceASIO-Replication", version: "3.4.2" }, os: { type: "Linux", name: "Red Hat Enterprise Linux Server release 6.7 (Santiago)", architecture: "x86_64", version: "Kernel 2.6.32-573.el6.x86_64" } }
--02T17::15.744+ I NETWORK [thread1] connection accepted from 192.168.244.30: # ( connections now open)
--02T17::15.745+ I NETWORK [conn2] received client metadata from 192.168.244.30: conn2: { driver: { name: "NetworkInterfaceASIO-Replication", version: "3.4.2" }, os: { type: "Linux", name: "Red Hat Enterprise Linux Server release 6.7 (Santiago)", architecture: "x86_64", version: "Kernel 2.6.32-573.el6.x86_64" } }
--02T17::17.802+ I REPL [rsBackgroundSync] sync source candidate: node3:
--02T17::17.873+ I ASIO [NetworkInterfaceASIO-RS-] Connecting to node3:
--02T17::17.875+ I ASIO [NetworkInterfaceASIO-RS-] Successfully connected to node3:
--02T17::18.203+ I ASIO [NetworkInterfaceASIO-RS-] Connecting to node3:
--02T17::18.211+ I ASIO [NetworkInterfaceASIO-RS-] Successfully connected to node3:
参考
1. 《MongoDB实战》
2. 《MongoDB权威指南》
3. 官方文档