Hi Krishna ,
If your DB2 system is the backend DB of an SAP system then the users that are generally set to non expirable are sap<sid> , sap<sid>db ( if java ), sapadm etc .
Normally an SAP system is installed with the confidence that it is highly available , ie it is available for end user to access 24/7
The SAP connects to the DB using the sap<sid> user and incase this user gets expired all the db operations will be hanging back eventually failing . (The user password will expire any time )This does not help in assuring that the system is HA/ near HA . [A time critical job might fail , an important update might fail]
Hence we set the passsword to never expirable .
If their is a password policy for the client such that every password should be changed then the above comes in conflict . You have the option to define a process to cater this . Normally the password is changed every quarter/year depending on the security policy
Thanks ,
Manu
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