QuorumPeer (Apache ZooKeeper - Server 3.6.1 API)

java.lang.Object
- java.lang.Thread
- - org.apache.zookeeper.server.ZooKeeperThread
  - - org.apache.zookeeper.server.quorum.QuorumPeer

All Implemented Interfaces:

Runnable, QuorumStats.Provider
```
public class QuorumPeer
extends ZooKeeperThread
implements QuorumStats.Provider
```
This class manages the quorum protocol. There are three states this server can be in:
1. Leader election - each server will elect a leader (proposing itself as a leader initially).
2. Follower - the server will synchronize with the leader and replicate any transactions.
3. Leader - the server will process requests and forward them to followers. A majority of followers must log the request before it can be accepted.
This class will setup a datagram socket that will always respond with its view of the current leader. The response will take the form of:
```
 int xid;

 long myid;

 long leader_id;

 long leader_zxid;
 
```
The request for the current leader will consist solely of an xid: int xid;

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`QuorumPeer.AddressTuple`
`static class`	`QuorumPeer.LearnerType`
`static class`	`QuorumPeer.QuorumServer`
`static class`	`QuorumPeer.ServerState`
`static class`	`QuorumPeer.SyncMode` (Used for monitoring) When peer is in synchronization phase, this shows which synchronization mechanism is being used
`static class`	`QuorumPeer.ZabState` (Used for monitoring) shows the current phase of Zab protocol that peer is running.

Nested classes/interfaces inherited from class java.lang.Thread
Thread.State, Thread.UncaughtExceptionHandler

Field Summary

Fields
Modifier and Type	Field and Description
`static String`	`ACCEPTED_EPOCH_FILENAME`
`protected int`	`clientPortListenBacklog` The ZooKeeper server's socket backlog length.
`static String`	`CONFIG_DEFAULT_MULTI_ADDRESS_ENABLED`
`static String`	`CONFIG_KEY_MULTI_ADDRESS_ENABLED`
`static String`	`CONFIG_KEY_MULTI_ADDRESS_REACHABILITY_CHECK_ENABLED`
`static String`	`CONFIG_KEY_MULTI_ADDRESS_REACHABILITY_CHECK_TIMEOUT_MS`
`protected int`	`connectToLearnerMasterLimit` The number of ticks that can pass before retrying to connect to learner master
`static String`	`CURRENT_EPOCH_FILENAME`
`long`	`end_fle`
`static String`	`FLE_TIME_UNIT`
`Follower`	`follower`
`protected int`	`initLimit` The number of ticks that the initial synchronization phase can take
`Leader`	`leader`
`protected boolean`	`localSessionsEnabled` Whether learners in this quorum should create new sessions as local.
`protected boolean`	`localSessionsUpgradingEnabled` Whether learners in this quorum should upgrade local sessions to global.
`protected int`	`maxSessionTimeout` Maximum number of milliseconds to allow for session timeout.
`protected int`	`minSessionTimeout` Minimum number of milliseconds to allow for session timeout.
`Observer`	`observer`
`static String`	`QUORUM_CNXN_TIMEOUT_MS`
`protected int`	`quorumCnxnThreadsSize` The maximum number of threads to allow in the connectionExecutors thread pool which will be used to initiate quorum server connections.
`protected String`	`quorumLearnerLoginContext` Quorum learner login context name in jaas-conf file to read the kerberos security details.
`protected boolean`	`quorumLearnerSaslAuthRequired` If this is false, quorum peer learner will talk to quorum peer server without authentication.
`protected boolean`	`quorumListenOnAllIPs` Whether or not to listen on all IPs for the two quorum ports (broadcast and fast leader election).
`protected boolean`	`quorumSaslEnableAuth` Enable/Disables quorum authentication using sasl.
`protected String`	`quorumServerLoginContext` Quorum server login context name in jaas-conf file to read the kerberos security details.
`protected boolean`	`quorumServerSaslAuthRequired` If this is false, quorum peer server will accept another quorum peer client connection even if the authentication did not succeed.
`protected String`	`quorumServicePrincipal` Kerberos quorum service principal.
`long`	`start_fle`
`static String`	`SYNC_ENABLED` The syncEnabled can also be set via a system property.
`protected boolean`	`syncEnabled` Enables/Disables sync request processor.
`protected int`	`syncLimit` The number of ticks that can pass between sending a request and getting an acknowledgment
`protected AtomicInteger`	`tick` The current tick
`protected int`	`tickTime` The number of milliseconds of each tick

Fields inherited from class java.lang.Thread
MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Fields inherited from interface org.apache.zookeeper.server.quorum.QuorumStats.Provider
FOLLOWING_STATE, LEADING_STATE, LOOKING_STATE, OBSERVING_STATE, UNKNOWN_STATE

Constructor Summary

Constructors
Constructor and Description
`QuorumPeer()`
`QuorumPeer(Map<Long,QuorumPeer.QuorumServer> quorumPeers, File snapDir, File logDir, int clientPort, int electionAlg, long myid, int tickTime, int initLimit, int syncLimit, int connectToLearnerMasterLimit)` This constructor is only used by the existing unit test code.
`QuorumPeer(Map<Long,QuorumPeer.QuorumServer> quorumPeers, File snapDir, File logDir, int clientPort, int electionAlg, long myid, int tickTime, int initLimit, int syncLimit, int connectToLearnerMasterLimit, QuorumVerifier quorumConfig)` This constructor is only used by the existing unit test code.
`QuorumPeer(Map<Long,QuorumPeer.QuorumServer> quorumPeers, File dataDir, File dataLogDir, int electionType, long myid, int tickTime, int initLimit, int syncLimit, int connectToLearnerMasterLimit, boolean quorumListenOnAllIPs, ServerCnxnFactory cnxnFactory, QuorumVerifier quorumConfig)`
`QuorumPeer(Map<Long,QuorumPeer.QuorumServer> quorumPeers, File dataDir, File dataLogDir, int electionType, long myid, int tickTime, int initLimit, int syncLimit, int connectToLearnerMasterLimit, ServerCnxnFactory cnxnFactory)` For backward compatibility purposes, we instantiate QuorumMaj by default.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`areLocalSessionsEnabled()` Whether local sessions are enabled
`void`	`closeAllConnections()`
`QuorumVerifier`	`configFromString(String s)`
`protected static int`	`countParticipants(Map<Long,QuorumPeer.QuorumServer> peers)` Count the number of nodes in the map that could be followers.
`QuorumCnxManager`	`createCnxnManager()`
`protected Election`	`createElectionAlgorithm(int electionAlgorithm)`
`void`	`enableLocalSessions(boolean flag)` Whether to enable local sessions
`void`	`enableLocalSessionsUpgrading(boolean flag)` Whether to allow local sessions to upgrade to global sessions
`long`	`getAcceptedEpoch()`
`ZooKeeperServer`	`getActiveServer()`
`InetSocketAddress`	`getClientAddress()`
`int`	`getClientPort()`
`int`	`getClientPortListenBacklog()` The server socket's listen backlog length
`int`	`getConnectToLearnerMasterLimit()` Get the connectToLearnerMasterLimit
`Set<Long>`	`getCurrentAndNextConfigVoters()`
`long`	`getCurrentEpoch()`
`Vote`	`getCurrentVote()`
`String`	`getDetailedPeerState()`
`MultipleAddresses`	`getElectionAddress()`
`Election`	`getElectionAlg()` Get an instance of LeaderElection
`int`	`getElectionType()` Gets the election type
`long`	`getId()` get the id of this quorum peer.
`String`	`getInitialConfig()`
`int`	`getInitLimit()` Get the number of ticks that the initial synchronization phase can take
`long`	`getLastLoggedZxid()` returns the highest zxid that this host has seen
`QuorumVerifier`	`getLastSeenQuorumVerifier()` Return QuorumVerifier object for the last proposed configuration.
`String`	`getLeaderAddress()`
`long`	`getLeaderId()`
`QuorumPeer.LearnerType`	`getLearnerType()`
`int`	`getMaxClientCnxnsPerHost()` Maximum number of connections allowed from particular host (ip)
`int`	`getMaxSessionTimeout()` maximum session timeout in milliseconds
`int`	`getMinSessionTimeout()` minimum session timeout in milliseconds
`int`	`getMultiAddressReachabilityCheckTimeoutMs()`
`String`	`getNextDynamicConfigFilename()`
`int`	`getObserverMasterPort()`
`Map<Long,QuorumPeer.QuorumServer>`	`getObservingView()` Returns only observers, no followers.
`QuorumPeer.ServerState`	`getPeerState()`
`MultipleAddresses`	`getQuorumAddress()`
`QuorumCnxManager`	`getQuorumCnxManager()` get reference to QuorumCnxManager
`boolean`	`getQuorumListenOnAllIPs()`
`String[]`	`getQuorumPeers()` Only used by QuorumStats at the moment
`int`	`getQuorumSize()`
`QuorumVerifier`	`getQuorumVerifier()` Return QuorumVerifier object for the last committed configuration.
`String`	`getServerState()`
`Integer`	`getSynced_observers_metric()`
`boolean`	`getSyncEnabled()` Return syncEnabled.
`int`	`getSyncLimit()` Get the synclimit
`QuorumPeer.SyncMode`	`getSyncMode()`
`int`	`getTick()` Get the current tick
`int`	`getTickTime()` Get the number of milliseconds of each tick
`FileTxnSnapLog`	`getTxnFactory()`
`Map<Long,QuorumPeer.QuorumServer>`	`getView()` A 'view' is a node's current opinion of the membership of the entire ensemble.
`Map<Long,QuorumPeer.QuorumServer>`	`getVotingView()` Observers are not contained in this view, only nodes with PeerType=PARTICIPANT.
`QuorumPeer.ZabState`	`getZabState()`
`protected ZKDatabase`	`getZkDb()`
`void`	`initConfigInZKDatabase()`
`void`	`initialize()`
`boolean`	`isLocalSessionsUpgradingEnabled()` Whether local sessions are allowed to upgrade to global sessions
`boolean`	`isMultiAddressEnabled()`
`boolean`	`isMultiAddressReachabilityCheckEnabled()`
`boolean`	`isReconfigStateChange()`
`boolean`	`isRunning()`
`boolean`	`isSslQuorum()`
`protected Follower`	`makeFollower(FileTxnSnapLog logFactory)`
`protected Leader`	`makeLeader(FileTxnSnapLog logFactory)`
`protected Election`	`makeLEStrategy()`
`protected Observer`	`makeObserver(FileTxnSnapLog logFactory)`
`boolean`	`processReconfig(QuorumVerifier qv, Long suggestedLeaderId, Long zxid, boolean restartLE)`
`void`	`reconfigFlagClear()`
`void`	`reconfigFlagSet()`
`void`	`recreateSocketAddresses(long id)` Resolves hostname for a given server ID.
`void`	`restartLeaderElection(QuorumVerifier qvOLD, QuorumVerifier qvNEW)`
`void`	`run()`
`void`	`setAcceptedEpoch(long e)`
`void`	`setClientPortListenBacklog(int backlog)` Sets the server socket's listen backlog length.
`void`	`setCnxnFactory(ServerCnxnFactory cnxnFactory)`
`protected void`	`setConfigFileName(String s)`
`void`	`setConnectToLearnerMasterLimit(int connectToLearnerMasterLimit)` Set the connectToLearnerMasterLimit
`void`	`setCurrentEpoch(long e)`
`void`	`setCurrentVote(Vote v)`
`void`	`setElectionType(int electionType)` Sets the election type
`protected void`	`setFollower(Follower newFollower)`
`void`	`setInitialConfig(String initialConfig)`
`void`	`setInitLimit(int initLimit)` Set the number of ticks that the initial synchronization phase can take
`void`	`setJvmPauseMonitor(JvmPauseMonitor jvmPauseMonitor)`
`void`	`setLastSeenQuorumVerifier(QuorumVerifier qv, boolean writeToDisk)`
`protected void`	`setLeader(Leader newLeader)`
`void`	`setLeaderAddressAndId(MultipleAddresses addr, long newId)`
`void`	`setLearnerType(QuorumPeer.LearnerType p)` Sets the LearnerType
`void`	`setMaxSessionTimeout(int max)` maximum session timeout in milliseconds
`void`	`setMinSessionTimeout(int min)` minimum session timeout in milliseconds
`void`	`setMultiAddressEnabled(boolean multiAddressEnabled)`
`void`	`setMultiAddressReachabilityCheckEnabled(boolean multiAddressReachabilityCheckEnabled)`
`void`	`setMultiAddressReachabilityCheckTimeoutMs(int multiAddressReachabilityCheckTimeoutMs)`
`void`	`setMyid(long myid)` set the id of this quorum peer.
`protected void`	`setObserver(Observer newObserver)`
`void`	`setObserverMasterPort(int observerMasterPort)`
`void`	`setPeerState(QuorumPeer.ServerState newState)`
`void`	`setQuorumListenOnAllIPs(boolean quorumListenOnAllIPs)`
`QuorumVerifier`	`setQuorumVerifier(QuorumVerifier qv, boolean writeToDisk)`
`void`	`setSecureCnxnFactory(ServerCnxnFactory secureCnxnFactory)`
`void`	`setSslQuorum(boolean sslQuorum)`
`void`	`setSyncEnabled(boolean syncEnabled)` Set syncEnabled.
`void`	`setSyncLimit(int syncLimit)` Set the synclimit
`void`	`setSyncMode(QuorumPeer.SyncMode syncMode)`
`void`	`setTickTime(int tickTime)` Set the number of milliseconds of each tick
`void`	`setTxnFactory(FileTxnSnapLog factory)`
`void`	`setUsePortUnification(boolean shouldUsePortUnification)`
`void`	`setZabState(QuorumPeer.ZabState zabState)`
`void`	`setZKDatabase(ZKDatabase database)` set zk database for this node
`void`	`setZooKeeperServer(ZooKeeperServer zks)`
`boolean`	`shouldUsePortUnification()`
`void`	`shutdown()`
`void`	`start()`
`void`	`startLeaderElection()`
`void`	`stopLeaderElection()`
`static QuorumPeer`	`testingQuorumPeer()`
`protected void`	`updateElectionVote(long newEpoch)` Updates leader election info to avoid inconsistencies when a new server tries to join the ensemble.
`boolean`	`viewContains(Long sid)` Check if a node is in the current view.

Methods inherited from class org.apache.zookeeper.server.ZooKeeperThread
handleException

Methods inherited from class java.lang.Thread
activeCount, checkAccess, clone, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail
- CONFIG_KEY_MULTI_ADDRESS_ENABLED
```
public static final String CONFIG_KEY_MULTI_ADDRESS_ENABLED
```
  See Also:
  
  Constant Field Values
- CONFIG_DEFAULT_MULTI_ADDRESS_ENABLED
```
public static final String CONFIG_DEFAULT_MULTI_ADDRESS_ENABLED
```
  See Also:
  
  Constant Field Values
- CONFIG_KEY_MULTI_ADDRESS_REACHABILITY_CHECK_TIMEOUT_MS
```
public static final String CONFIG_KEY_MULTI_ADDRESS_REACHABILITY_CHECK_TIMEOUT_MS
```
  See Also:
  
  Constant Field Values
- CONFIG_KEY_MULTI_ADDRESS_REACHABILITY_CHECK_ENABLED
```
public static final String CONFIG_KEY_MULTI_ADDRESS_REACHABILITY_CHECK_ENABLED
```
  See Also:
  
  Constant Field Values
- start_fle
```
public long start_fle
```
- end_fle
```
public long end_fle
```
- FLE_TIME_UNIT
```
public static final String FLE_TIME_UNIT
```
  See Also:
  
  Constant Field Values
- tickTime
```
protected int tickTime
```
  The number of milliseconds of each tick
- localSessionsEnabled
```
protected boolean localSessionsEnabled
```
  Whether learners in this quorum should create new sessions as local. False by default to preserve existing behavior.
- localSessionsUpgradingEnabled
```
protected boolean localSessionsUpgradingEnabled
```
  Whether learners in this quorum should upgrade local sessions to global. Only matters if local sessions are enabled.
- minSessionTimeout
```
protected int minSessionTimeout
```
  Minimum number of milliseconds to allow for session timeout. A value of -1 indicates unset, use default.
- maxSessionTimeout
```
protected int maxSessionTimeout
```
  Maximum number of milliseconds to allow for session timeout. A value of -1 indicates unset, use default.
- clientPortListenBacklog
```
protected int clientPortListenBacklog
```
  The ZooKeeper server's socket backlog length. The number of connections that will be queued to be read before new connections are dropped. A value of one indicates the default backlog will be used.
- initLimit
```
protected volatile int initLimit
```
  The number of ticks that the initial synchronization phase can take
- syncLimit
```
protected volatile int syncLimit
```
  The number of ticks that can pass between sending a request and getting an acknowledgment
- connectToLearnerMasterLimit
```
protected volatile int connectToLearnerMasterLimit
```
  The number of ticks that can pass before retrying to connect to learner master
- syncEnabled
```
protected boolean syncEnabled
```
  Enables/Disables sync request processor. This option is enabled by default and is to be used with observers.
- tick
```
protected AtomicInteger tick
```
  The current tick
- quorumListenOnAllIPs
```
protected boolean quorumListenOnAllIPs
```
  Whether or not to listen on all IPs for the two quorum ports (broadcast and fast leader election).
- quorumSaslEnableAuth
```
protected boolean quorumSaslEnableAuth
```
  Enable/Disables quorum authentication using sasl. Defaulting to false.
- quorumServerSaslAuthRequired
```
protected boolean quorumServerSaslAuthRequired
```
  If this is false, quorum peer server will accept another quorum peer client connection even if the authentication did not succeed. This can be used while upgrading ZooKeeper server. Defaulting to false (required).
- quorumLearnerSaslAuthRequired
```
protected boolean quorumLearnerSaslAuthRequired
```
  If this is false, quorum peer learner will talk to quorum peer server without authentication. This can be used while upgrading ZooKeeper server. Defaulting to false (required).
- quorumServicePrincipal
```
protected String quorumServicePrincipal
```
  Kerberos quorum service principal. Defaulting to 'zkquorum/localhost'.
- quorumLearnerLoginContext
```
protected String quorumLearnerLoginContext
```
  Quorum learner login context name in jaas-conf file to read the kerberos security details. Defaulting to 'QuorumLearner'.
- quorumServerLoginContext
```
protected String quorumServerLoginContext
```
  Quorum server login context name in jaas-conf file to read the kerberos security details. Defaulting to 'QuorumServer'.
- quorumCnxnThreadsSize
```
protected int quorumCnxnThreadsSize
```
  The maximum number of threads to allow in the connectionExecutors thread pool which will be used to initiate quorum server connections.
- QUORUM_CNXN_TIMEOUT_MS
```
public static final String QUORUM_CNXN_TIMEOUT_MS
```
  See Also:
  
  Constant Field Values
- follower
```
public Follower follower
```
- leader
```
public Leader leader
```
- observer
```
public Observer observer
```
- SYNC_ENABLED
```
public static final String SYNC_ENABLED
```
  The syncEnabled can also be set via a system property.
  
  See Also:
  
  Constant Field Values
- CURRENT_EPOCH_FILENAME
```
public static final String CURRENT_EPOCH_FILENAME
```
  See Also:
  
  Constant Field Values
- ACCEPTED_EPOCH_FILENAME
```
public static final String ACCEPTED_EPOCH_FILENAME
```
  See Also:
  
  Constant Field Values

Constructor Detail

QuorumPeer

public QuorumPeer()
           throws SaslException

Throws:: SaslException

QuorumPeer

public QuorumPeer(Map<Long,QuorumPeer.QuorumServer> quorumPeers,
                  File dataDir,
                  File dataLogDir,
                  int electionType,
                  long myid,
                  int tickTime,
                  int initLimit,
                  int syncLimit,
                  int connectToLearnerMasterLimit,
                  ServerCnxnFactory cnxnFactory)
           throws IOException

For backward compatibility purposes, we instantiate QuorumMaj by default.

Throws:: IOException

QuorumPeer

public QuorumPeer(Map<Long,QuorumPeer.QuorumServer> quorumPeers,
                  File dataDir,
                  File dataLogDir,
                  int electionType,
                  long myid,
                  int tickTime,
                  int initLimit,
                  int syncLimit,
                  int connectToLearnerMasterLimit,
                  boolean quorumListenOnAllIPs,
                  ServerCnxnFactory cnxnFactory,
                  QuorumVerifier quorumConfig)
           throws IOException

Throws:: IOException

QuorumPeer

public QuorumPeer(Map<Long,QuorumPeer.QuorumServer> quorumPeers,
                  File snapDir,
                  File logDir,
                  int clientPort,
                  int electionAlg,
                  long myid,
                  int tickTime,
                  int initLimit,
                  int syncLimit,
                  int connectToLearnerMasterLimit)
           throws IOException

This constructor is only used by the existing unit test code. It defaults to FileLogProvider persistence provider.

Throws:: IOException

QuorumPeer

public QuorumPeer(Map<Long,QuorumPeer.QuorumServer> quorumPeers,
                  File snapDir,
                  File logDir,
                  int clientPort,
                  int electionAlg,
                  long myid,
                  int tickTime,
                  int initLimit,
                  int syncLimit,
                  int connectToLearnerMasterLimit,
                  QuorumVerifier quorumConfig)
           throws IOException

This constructor is only used by the existing unit test code. It defaults to FileLogProvider persistence provider.

Throws:: IOException

Method Detail

getObserverMasterPort
```
public int getObserverMasterPort()
```

setObserverMasterPort

public void setObserverMasterPort(int observerMasterPort)

isMultiAddressEnabled

public boolean isMultiAddressEnabled()

setMultiAddressEnabled

public void setMultiAddressEnabled(boolean multiAddressEnabled)

getMultiAddressReachabilityCheckTimeoutMs

public int getMultiAddressReachabilityCheckTimeoutMs()

setMultiAddressReachabilityCheckTimeoutMs

public void setMultiAddressReachabilityCheckTimeoutMs(int multiAddressReachabilityCheckTimeoutMs)

isMultiAddressReachabilityCheckEnabled

public boolean isMultiAddressReachabilityCheckEnabled()

setMultiAddressReachabilityCheckEnabled

public void setMultiAddressReachabilityCheckEnabled(boolean multiAddressReachabilityCheckEnabled)

getLearnerType

public QuorumPeer.LearnerType getLearnerType()

setLearnerType

public void setLearnerType(QuorumPeer.LearnerType p)

Sets the LearnerType

setConfigFileName

protected void setConfigFileName(String s)

getQuorumSize
```
public int getQuorumSize()
```

setJvmPauseMonitor

public void setJvmPauseMonitor(JvmPauseMonitor jvmPauseMonitor)

getId
```
public long getId()
```
get the id of this quorum peer.

Overrides:

getId in class Thread

isSslQuorum
```
public boolean isSslQuorum()
```

shouldUsePortUnification

public boolean shouldUsePortUnification()

getCurrentVote
```
public Vote getCurrentVote()
```

setCurrentVote
```
public void setCurrentVote(Vote v)
```

setPeerState

public void setPeerState(QuorumPeer.ServerState newState)

setZabState

public void setZabState(QuorumPeer.ZabState zabState)

setSyncMode

public void setSyncMode(QuorumPeer.SyncMode syncMode)

getZabState

public QuorumPeer.ZabState getZabState()

getSyncMode

public QuorumPeer.SyncMode getSyncMode()

setLeaderAddressAndId

public void setLeaderAddressAndId(MultipleAddresses addr,
                                  long newId)

getLeaderAddress
```
public String getLeaderAddress()
```

getLeaderId
```
public long getLeaderId()
```

getDetailedPeerState
```
public String getDetailedPeerState()
```

reconfigFlagSet
```
public void reconfigFlagSet()
```

reconfigFlagClear
```
public void reconfigFlagClear()
```

isReconfigStateChange

public boolean isReconfigStateChange()

getPeerState

public QuorumPeer.ServerState getPeerState()

recreateSocketAddresses
```
public void recreateSocketAddresses(long id)
```
Resolves hostname for a given server ID. This method resolves hostname for a given server ID in both quorumVerifer and lastSeenQuorumVerifier. If the server ID matches the local server ID, it also updates myAddrs.

getQuorumAddress

public MultipleAddresses getQuorumAddress()

getElectionAddress

public MultipleAddresses getElectionAddress()

getClientAddress

public InetSocketAddress getClientAddress()

testingQuorumPeer

public static QuorumPeer testingQuorumPeer()
                                    throws SaslException

Throws:: SaslException

initialize

public void initialize()
                throws SaslException

Throws:: SaslException

start
```
public void start()
```
Overrides:

start in class Thread

stopLeaderElection
```
public void stopLeaderElection()
```

startLeaderElection
```
public void startLeaderElection()
```

countParticipants
```
protected static int countParticipants(Map<Long,QuorumPeer.QuorumServer> peers)
```
Count the number of nodes in the map that could be followers.

Parameters:

peers -

Returns:

The number of followers in the map

getLastLoggedZxid
```
public long getLastLoggedZxid()
```
returns the highest zxid that this host has seen

Returns:

the highest zxid for this host

makeFollower

protected Follower makeFollower(FileTxnSnapLog logFactory)
                         throws IOException

Throws:: IOException

makeLeader

protected Leader makeLeader(FileTxnSnapLog logFactory)
                     throws IOException,
                            X509Exception

Throws:: IOException; X509Exception

makeObserver

protected Observer makeObserver(FileTxnSnapLog logFactory)
                         throws IOException

Throws:: IOException

createElectionAlgorithm

protected Election createElectionAlgorithm(int electionAlgorithm)

makeLEStrategy
```
protected Election makeLEStrategy()
```

setLeader

protected void setLeader(Leader newLeader)

setFollower

protected void setFollower(Follower newFollower)

setObserver

protected void setObserver(Observer newObserver)

getActiveServer

public ZooKeeperServer getActiveServer()

run
```
public void run()
```
Specified by:

run in interface Runnable

Overrides:

run in class Thread

shutdown
```
public void shutdown()
```

getView
```
public Map<Long,QuorumPeer.QuorumServer> getView()
```
A 'view' is a node's current opinion of the membership of the entire ensemble.

getVotingView
```
public Map<Long,QuorumPeer.QuorumServer> getVotingView()
```
Observers are not contained in this view, only nodes with PeerType=PARTICIPANT.

getObservingView

public Map<Long,QuorumPeer.QuorumServer> getObservingView()

Returns only observers, no followers.

getCurrentAndNextConfigVoters

public Set<Long> getCurrentAndNextConfigVoters()

viewContains
```
public boolean viewContains(Long sid)
```
Check if a node is in the current view. With static membership, the result of this check will never change; only when dynamic membership is introduced will this be more useful.

getQuorumPeers
```
public String[] getQuorumPeers()
```
Only used by QuorumStats at the moment

Specified by:

getQuorumPeers in interface QuorumStats.Provider

getServerState
```
public String getServerState()
```
Specified by:

getServerState in interface QuorumStats.Provider

setMyid
```
public void setMyid(long myid)
```
set the id of this quorum peer.

setInitialConfig

public void setInitialConfig(String initialConfig)

getInitialConfig
```
public String getInitialConfig()
```

getTickTime
```
public int getTickTime()
```
Get the number of milliseconds of each tick

setTickTime
```
public void setTickTime(int tickTime)
```
Set the number of milliseconds of each tick

getMaxClientCnxnsPerHost
```
public int getMaxClientCnxnsPerHost()
```
Maximum number of connections allowed from particular host (ip)

areLocalSessionsEnabled
```
public boolean areLocalSessionsEnabled()
```
Whether local sessions are enabled

enableLocalSessions
```
public void enableLocalSessions(boolean flag)
```
Whether to enable local sessions

isLocalSessionsUpgradingEnabled
```
public boolean isLocalSessionsUpgradingEnabled()
```
Whether local sessions are allowed to upgrade to global sessions

enableLocalSessionsUpgrading
```
public void enableLocalSessionsUpgrading(boolean flag)
```
Whether to allow local sessions to upgrade to global sessions

getMinSessionTimeout
```
public int getMinSessionTimeout()
```
minimum session timeout in milliseconds

setMinSessionTimeout
```
public void setMinSessionTimeout(int min)
```
minimum session timeout in milliseconds

getMaxSessionTimeout
```
public int getMaxSessionTimeout()
```
maximum session timeout in milliseconds

setMaxSessionTimeout
```
public void setMaxSessionTimeout(int max)
```
maximum session timeout in milliseconds

getClientPortListenBacklog
```
public int getClientPortListenBacklog()
```
The server socket's listen backlog length

setClientPortListenBacklog
```
public void setClientPortListenBacklog(int backlog)
```
Sets the server socket's listen backlog length.

getInitLimit
```
public int getInitLimit()
```
Get the number of ticks that the initial synchronization phase can take

setInitLimit
```
public void setInitLimit(int initLimit)
```
Set the number of ticks that the initial synchronization phase can take

getTick
```
public int getTick()
```
Get the current tick

configFromString

public QuorumVerifier configFromString(String s)
                                throws IOException,
                                       QuorumPeerConfig.ConfigException

Throws:: IOException; QuorumPeerConfig.ConfigException

getQuorumVerifier
```
public QuorumVerifier getQuorumVerifier()
```
Return QuorumVerifier object for the last committed configuration.

getLastSeenQuorumVerifier
```
public QuorumVerifier getLastSeenQuorumVerifier()
```
Return QuorumVerifier object for the last proposed configuration.

restartLeaderElection

public void restartLeaderElection(QuorumVerifier qvOLD,
                                  QuorumVerifier qvNEW)

getNextDynamicConfigFilename

public String getNextDynamicConfigFilename()

setLastSeenQuorumVerifier

public void setLastSeenQuorumVerifier(QuorumVerifier qv,
                                      boolean writeToDisk)

setQuorumVerifier

public QuorumVerifier setQuorumVerifier(QuorumVerifier qv,
                                        boolean writeToDisk)

getElectionAlg
```
public Election getElectionAlg()
```
Get an instance of LeaderElection

getSyncLimit
```
public int getSyncLimit()
```
Get the synclimit

setSyncLimit

public void setSyncLimit(int syncLimit)

Set the synclimit

getConnectToLearnerMasterLimit
```
public int getConnectToLearnerMasterLimit()
```
Get the connectToLearnerMasterLimit

setConnectToLearnerMasterLimit

public void setConnectToLearnerMasterLimit(int connectToLearnerMasterLimit)

Set the connectToLearnerMasterLimit

getSyncEnabled
```
public boolean getSyncEnabled()
```
Return syncEnabled.

Returns:

setSyncEnabled
```
public void setSyncEnabled(boolean syncEnabled)
```
Set syncEnabled.

Parameters:

syncEnabled -

getElectionType
```
public int getElectionType()
```
Gets the election type

setElectionType

public void setElectionType(int electionType)

Sets the election type

getQuorumListenOnAllIPs

public boolean getQuorumListenOnAllIPs()

setQuorumListenOnAllIPs

public void setQuorumListenOnAllIPs(boolean quorumListenOnAllIPs)

setCnxnFactory

public void setCnxnFactory(ServerCnxnFactory cnxnFactory)

setSecureCnxnFactory

public void setSecureCnxnFactory(ServerCnxnFactory secureCnxnFactory)

setSslQuorum

public void setSslQuorum(boolean sslQuorum)

setUsePortUnification

public void setUsePortUnification(boolean shouldUsePortUnification)

setZooKeeperServer

public void setZooKeeperServer(ZooKeeperServer zks)

closeAllConnections
```
public void closeAllConnections()
```

getClientPort
```
public int getClientPort()
```

setTxnFactory

public void setTxnFactory(FileTxnSnapLog factory)

getTxnFactory
```
public FileTxnSnapLog getTxnFactory()
```

setZKDatabase
```
public void setZKDatabase(ZKDatabase database)
```
set zk database for this node

Parameters:

database -

getZkDb
```
protected ZKDatabase getZkDb()
```

initConfigInZKDatabase
```
public void initConfigInZKDatabase()
```

isRunning
```
public boolean isRunning()
```

getQuorumCnxManager
```
public QuorumCnxManager getQuorumCnxManager()
```
get reference to QuorumCnxManager

getCurrentEpoch

public long getCurrentEpoch()
                     throws IOException

Throws:: IOException

getAcceptedEpoch

public long getAcceptedEpoch()
                      throws IOException

Throws:: IOException

setCurrentEpoch

public void setCurrentEpoch(long e)
                     throws IOException

Throws:: IOException

setAcceptedEpoch

public void setAcceptedEpoch(long e)
                      throws IOException

Throws:: IOException

processReconfig

public boolean processReconfig(QuorumVerifier qv,
                               Long suggestedLeaderId,
                               Long zxid,
                               boolean restartLE)

updateElectionVote
```
protected void updateElectionVote(long newEpoch)
```
Updates leader election info to avoid inconsistencies when a new server tries to join the ensemble. Here is the inconsistency scenario we try to solve by updating the peer epoch after following leader: Let's say we have an ensemble with 3 servers z1, z2 and z3. 1. z1, z2 were following z3 with peerEpoch to be 0xb8, the new epoch is 0xb9, aka current accepted epoch on disk. 2. z2 get restarted, which will use 0xb9 as it's peer epoch when loading the current accept epoch from disk. 3. z2 received notification from z1 and z3, which is following z3 with epoch 0xb8, so it started following z3 again with peer epoch 0xb8. 4. before z2 successfully connected to z3, z3 get restarted with new epoch 0xb9. 5. z2 will retry around a few round (default 5s) before giving up, meanwhile it will report z3 as leader. 6. z1 restarted, and looking with peer epoch 0xb9. 7. z1 voted z3, and z3 was elected as leader again with peer epoch 0xb9. 8. z2 successfully connected to z3 before giving up, but with peer epoch 0xb8. 9. z1 get restarted, looking for leader with peer epoch 0xba, but cannot join, because z2 is reporting peer epoch 0xb8, while z3 is reporting 0xb9. By updating the election vote after actually following leader, we can avoid this kind of stuck happened. Btw, the zxid and electionEpoch could be inconsistent because of the same reason, it's better to update these as well after syncing with leader, but that required protocol change which is non trivial. This problem is worked around by skipping comparing the zxid and electionEpoch when counting for votes for out of election servers during looking for leader. See https://issues.apache.org/jira/browse/ZOOKEEPER-1732

createCnxnManager

public QuorumCnxManager createCnxnManager()

getSynced_observers_metric

@InterfaceAudience.Private
public Integer getSynced_observers_metric()

Class QuorumPeer

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Thread

Field Summary

Fields inherited from class java.lang.Thread

Fields inherited from interface org.apache.zookeeper.server.quorum.QuorumStats.Provider

Constructor Summary

Method Summary

Methods inherited from class org.apache.zookeeper.server.ZooKeeperThread

Methods inherited from class java.lang.Thread

Methods inherited from class java.lang.Object

Field Detail

CONFIG_KEY_MULTI_ADDRESS_ENABLED

CONFIG_DEFAULT_MULTI_ADDRESS_ENABLED

CONFIG_KEY_MULTI_ADDRESS_REACHABILITY_CHECK_TIMEOUT_MS

CONFIG_KEY_MULTI_ADDRESS_REACHABILITY_CHECK_ENABLED

start_fle

end_fle

FLE_TIME_UNIT

tickTime

localSessionsEnabled

localSessionsUpgradingEnabled

minSessionTimeout

maxSessionTimeout

clientPortListenBacklog

initLimit

syncLimit

connectToLearnerMasterLimit

syncEnabled

tick

quorumListenOnAllIPs

quorumSaslEnableAuth

quorumServerSaslAuthRequired

quorumLearnerSaslAuthRequired

quorumServicePrincipal

quorumLearnerLoginContext

quorumServerLoginContext

quorumCnxnThreadsSize

QUORUM_CNXN_TIMEOUT_MS

follower

leader

observer

SYNC_ENABLED

CURRENT_EPOCH_FILENAME

ACCEPTED_EPOCH_FILENAME

Constructor Detail

QuorumPeer

QuorumPeer

QuorumPeer

QuorumPeer

QuorumPeer

Method Detail

getObserverMasterPort

setObserverMasterPort

isMultiAddressEnabled

setMultiAddressEnabled

getMultiAddressReachabilityCheckTimeoutMs

setMultiAddressReachabilityCheckTimeoutMs

isMultiAddressReachabilityCheckEnabled

setMultiAddressReachabilityCheckEnabled

getLearnerType

setLearnerType

setConfigFileName

getQuorumSize

setJvmPauseMonitor

getId

isSslQuorum

shouldUsePortUnification

getCurrentVote

setCurrentVote

setPeerState

setZabState

setSyncMode

getZabState

getSyncMode

setLeaderAddressAndId

getLeaderAddress

getLeaderId

getDetailedPeerState

reconfigFlagSet