Clients with the failover property automatically reconnect to the secondary companion when the primary companion crashes or you issue shutdown or shutdown with nowait, triggering failover. To give a client the failover property, you must add a line labeled “hafailover” to the interfaces file to provide the information necessary for the client to connect to the secondary companion. You can add this line using either a file editor or the dsedit utility.
The following UNIX interfaces file entry is for an asymmetric configuration between the primary companion PERSONNEL1 and its secondary companion MONEY1. It includes an hafailover entry that enables clients connected to PERSONNEL1 to reconnect to MONEY1 during failover:
PERSONNEL1 master tcp /<host> <port> \x00029f7g82d63ce70000000000000000 query tli tcp /dev/tcp \x00029f7g82d63ce70000000000000000 hafailover MONEY1
The following is a Windows sql.ini entry for a symmetric configuration between the MONEY1 and PERSONNEL1 companions:
[MONEY1] query=TCP,FN1,9835 master=TCP,FN1,9835 hafailover=PERSONNEL1
[PERSONNEL1] query=TCP,HUM1,7586 master=TCP,HUM1,7586 hafailover=MONEY1
For more information about adding this information to the interfaces file, see the Open Client and Open Server Configuration Guide for your platform.
Client applications must resend any queries that were
interrupted by failover. Other information specific to the connection,
such as cursor declarations, will also need to be restored.
