com.sleepycat.je.rep.util
Class ReplicationGroupAdmin

java.lang.Object
  com.sleepycat.je.rep.util.ReplicationGroupAdmin

public class ReplicationGroupAdmin
extends Object

Administrative APIs for use by applications which do not have direct access to a replicated environment. The class supplies methods that can be used to list group members, remove members, update network addresses, and find the current master. Information is found and updated by querying nodes in the group. Because of that, ReplicationGroupAdmin can only obtain information when there is at least one node alive in the replication group.

Constructor Summary

ReplicationGroupAdmin(String groupName, Set<InetSocketAddress> helperSockets)
Constructs a group admin object.

Method Summary

ReplicationGroup	getGroup() Returns the current composition of the group from the Master.
String	getGroupName() Returns the name of the replication group.
Set<InetSocketAddress>	getHelperSockets() Returns the helper sockets being used to contact a replication group member, in order to query for the information.
String	getMasterNodeName() Returns the node name associated with the master
NodeState	getNodeState(ReplicationNode repNode, int socketConnectTimeout) Returns the state of a replicated node and state of the application where the node is running in.
void	removeMember(String nodeName) Removes this node from the group, so that it is no longer a member of the group.
void	updateAddress(String nodeName, String newHostName, int newPort) Update the network address for a specified member of the replication group.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ReplicationGroupAdmin

public ReplicationGroupAdmin(String groupName,
                             Set<InetSocketAddress> helperSockets)

Constructs a group admin object.

Parameters:

groupName - the name of the group to be administered

helperSockets - the sockets on which it can contact helper nodes in the replication group to carry out admin services.

Method Detail

getHelperSockets

public Set<InetSocketAddress> getHelperSockets()

Returns the helper sockets being used to contact a replication group member, in order to query for the information.

Returns:

the set of helper sockets.

getGroupName

public String getGroupName()

Returns the name of the replication group.

Returns:

the group name.

getMasterNodeName

public String getMasterNodeName()
                         throws UnknownMasterException,
                                EnvironmentFailureException

Returns the node name associated with the master

Returns:

the master node ID

Throws:

UnknownMasterException - if the master was not found

EnvironmentFailureException - if an unexpected, internal or environment-wide failure occurs.

removeMember

public void removeMember(String nodeName)
                  throws UnknownMasterException,
                         MemberNotFoundException,
                         MasterStateException,
                         EnvironmentFailureException

Removes this node from the group, so that it is no longer a member of the group. When removed, it will no longer be able to connect to a master, nor can it participate in elections. If the node is a Monitor it will no longer be informed of election results. Once removed, a node cannot be added again to the group under the same node name.

Ideally, the node being removed should be shut down before this call is issued.

If the node is an active Replica the master will terminate its connection with the node and will not allow the replica to reconnect with the group, since it's no longer a member of the group. If the node wishes to re-join it should do so with a different node name.

An active Master cannot be removed. It must first be shutdown, or transition to the Replica state before it can be removed from the group.

Parameters:

nodeName - identifies the node being removed from the group

Throws:

UnknownMasterException - if the master was not found

MemberNotFoundException - if the node denoted by nodeName is not a member of the replication group

MasterStateException - if the member being removed is currently the Master

EnvironmentFailureException - if an unexpected, internal or environment-wide failure occurs.

See Also:

Adding and Removing Nodes From the Group

getGroup

public ReplicationGroup getGroup()
                          throws UnknownMasterException,
                                 EnvironmentFailureException

Returns the current composition of the group from the Master.

Returns:

the group description

Throws:

UnknownMasterException - if the master was not found

EnvironmentFailureException - if an unexpected, internal or environment-wide failure occurs

getNodeState

public NodeState getNodeState(ReplicationNode repNode,
                              int socketConnectTimeout)
                       throws IOException,
                              com.sleepycat.je.rep.utilint.ServiceDispatcher.ServiceConnectFailedException

Returns the state of a replicated node and state of the application where the node is running in.

Parameters:

repNode - a ReplicationNode includes those information which are needed to connect to the node

socketConnectTimeout - the timeout value for creating a socket connection with the replicated node

Returns:

the state of the replicated node

Throws:

IOException - if the machine is down or no response is returned

com.sleepycat.je.rep.utilint.ServiceDispatcher.ServiceConnectFailedException - if can't connect to the service running on the replicated node

updateAddress

public void updateAddress(String nodeName,
                          String newHostName,
                          int newPort)
                   throws EnvironmentFailureException,
                          MasterStateException,
                          MemberNotFoundException,
                          ReplicaStateException,
                          UnknownMasterException

Update the network address for a specified member of the replication group. When updating the address of this target replication node, the node cannot be alive. One common use case is when the replication member must be moved to a new host, possibly because of machine failure.

To make a network address change, take these steps:

1. Shutdown the node that is being updated.
2. Use this method to change the hostname and port of the node.
3. Start the node on the new machine, or at its new port, using the new hostname/port. If the log files are available at the node, they will be reused. A network restore operation may need to be initiated by the application to copy over any needed log files if no log files are available, or if they have become obsolete.

Parameters:

nodeName - the name of the node whose address will be updated.

newHostName - the new host name of the node

newPort - the new port number of the node

Throws:

EnvironmentFailureException - if an unexpected, internal or environment-wide failure occurs

MasterStateException - if the member being updated is currently the master

MemberNotFoundException - if the node denoted by nodeName is not a member of the replication group

ReplicaStateException - if the member being updated is currently alive

UnknownMasterException - if the master was not found

See Also:

DbResetRepGroup, which can be used in a related but different use case to copy and move a group.