GemFire XD thin clients specify the client bind address and port of a
locator in order to connect to a GemFire XD cluster.
Connecting to a locator ensures that a client is load-balanced to an
available GemFire XD server in the distributed system. If the client's connection
to a server is dropped (for example, if the server is shut down), then the
client can retry connecting to the same locator to access another available
Note: Thin clients do not specify the peer discovery addresses or port as
do GemFire XD servers and peers.
For example, in an interactive gfxd session, use the
command and specify the client host and
port number of a locator:
connect client 'locator1host:1527';
In a third-party JDBC tool, specify the host and port in the JDBC
Locators balance client requests to all GemFire XD servers available in a
cluster, so multiple connection requests to the same locator may result in
connections to different servers.
When a client connects to a distributed system using a locator, by default the locator
provides the client the hostname
of an available datastore. You must ensure that
each hostname correctly maps to the IP address for each server (for example, in
). As an alternative, for systems that use only IP
addresses you can use the prefer-netserver-ipaddress
system property to provide server IP addresses to
When load balancing is enabled, clients may not be able to connect to a specific
server even if they provide that server's unique port number for client connections. If
a JDBC client needs to connect to a specific member, set load-balance
to "false" in the connection string and specify the connection details for a specific
GemFire XD member, rather than a locator. For
gfxd> connect client 'server_hostname:server_port/;load-balance=false'