HA_ALIAS configuration parameter

The HA_ALIAS configuration parameter defines a network alias that is used for server-to-server communication in a high-availability cluster. The specified network alias is also used by Connection Managers, the ifxclone utility, and onmode -d commands.

onconfig.std value
Not set. The HA_ALIAS configure parameter applies to high-availability cluster servers.
values
The HA_ALIAS configuration parameter value must match a DBSERVERNAME or DBSERVERALIASES configuration parameter value that is associated with a TCP sqlhosts file entry. If the DBSERVERNAME or the DBSERVERALIASES configuration parameter value includes the optional number of listener threads, omit the optional listener thread value from the HA_ALIAS configuration parameter value. For example, if DBSERVERNAME is set to my_server-4, HA_ALIAS is set to my_server.
takes effect
After you edit your onconfig file and restart the database server.
For the primary server in a high-availability cluster, reset the value dynamically in your onconfig file by running the onmode -wf command. This method does not work for secondary servers in a high-availability cluster.
For the primary server in a high-availability cluster, reset the value in memory by running the onmode -wm command. This method does not work for secondary servers in a high-availability cluster.

Usage

The HA_ALIAS configuration parameter is required for high-availability cluster servers that use shared-memory connections.

For example, if a high-availability cluster server's DBSERVERNAME configuration parameter is associated with a shared-memory sqlhosts file entry, set a DBSERVERALIAS configuration parameter and a matching HA_ALIAS configuration parameter value, and then create a TCP sqlhosts file entry for the for the alias.

onconfig file values:
DBSERVERNAME my_server
DBSERVERALIAS alias_1
HA_ALIAS alias_1
sqlhosts file values:
#dbservername  nettype   hostname  servicename  options
 my_server     onipcshm  host_1    port_1               #client-to-server
 alias_1       onsoctcp  host_1    port_2               #server-to-server 

Setting the HA_ALIAS configuration parameter for all servers in a high-availability cluster also enables you to separate client/server communication from server-to-server communication .


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