I had a similar issue where the policy name was dbadmin_Filesystem and the plociy just wouldn't start, I had to change the name to dbadm_Filesystem for it to run. I think some names are used by Netbackup and hence cannot be accepted as policy names.....

Servet, can you tell us the policy name, schedule name and client name please?

Here's a technote that describes some rules for the policy names:
http://seer.entsupport.symantec.com/docs/252403.htm

NBU limits number of failures of backup for each policy. You can control this behavior here:
 

In the "Scheduled backup attempts" you can see, that NBU will not try more than twice in 12 hours. You can increase the number of tries, reduce update interval and run nbpemreq -updatepolicies

This should help

I have removed the log files which are located under '/usr/openv/db/failure_history ' directory. Then the issue has been fixed.

FYI. Thanks for all coments.

Regards.

Servet

Probably related to what mouse mentioned - the "Scheduled backup attempts"

The T/N About the Global Attributes properties states:

"...

Schedule backup attempts

NetBackup considers the failure history of a policy to determine whether or not to run a scheduled backup job. The Schedule backup attempts property sets the timeframe for NetBackup to examine.

This property determines the following characteristics for each policy:

• How many preceding hours NetBackup examines to determine whether to allow another backup attempt (retry). By default, NetBackup examines the past 12 hours.

• How many times a backup can be retried within that timeframe. By default, NetBackup allows two attempts. Attempts include the scheduled backups that start automatically or the scheduled backups that are user-initiated.

Consider the following example scenario using the default setting 2 tries every 12 hours:

• Policy_A runs at 6:00 p.m.; Schedule_1 fails.

• Policy_A is user-initiated at 8:00 p.m.; Schedule_2 fails.

• At 11:00 p.m., NetBackup looks at the previous 12 hours. NetBackup sees one attempt at 6:00 p.m. and one attempt at 8:00 p.m. The Schedule backup attempts setting of two has been met so NetBackup does not try again.

• At 6:30 a.m. the next morning, NetBackup looks at the previous 12 hours. NetBackup sees only one attempt at 8:00 p.m. The Schedule backup attempts setting of two has not been met so NetBackup tries again. If a schedule window is not open at this time, NetBackup waits until a window is open.

Note:
This attribute does not apply to user backups and archives.

..."