This section explains the steps in redirecting clients with the INFORMIXSERVER environment variable and the connectivity strategy that supports this method.
The INFORMIXSERVER redirection method relies on the fact that when an application does not explicitly specify a database server in the CONNECT statement, the database server connects to the client that the INFORMIXSERVER environment variable specifies.
If one of the database servers in a replication pair is unusable, applications that use that database server can reset their INFORMIXSERVER environment variable to the other database server in the pair to access the same data.
Applications read the value of the INFORMIXSERVER environment variable only when they start. Therefore, applications must be restarted to recognize a change in the environment variable.
To support this method of redirection, you can use the following connectivity statements:
You cannot use the CONNECT TO database@dbserver or CONNECT TO @dbserver statements for this method. When a database server is explicitly named, the CONNECT statement does not use the INFORMIXSERVER environment variable to find a database server.
Administrators take no action to redirect the clients, but they might need to change the type of the database server.
Users who are running client applications must perform the following three steps when they decide to redirect clients with the INFORMIXSERVER environment variable.