RMAN recovery issues

Hello,

I have had a rough few days, trying to solve an issue with RMAN recovery process.

I am using NetWoker 8.2.0.1 Build 479 as a backup software with attached DD4500 with OS 5.7 version. Ora backups and restores are triggered from client side by application team.

Normal retention of the backups is 35 days, we are usually receiving request to extend the retention of certain backups (like in this case).

As an example:

We receive a request to extend the backups from 26th of August(inc0).

Issue occur when they tried to start the recovery process. All of the DBs that were extend started smoothly and everything was OK, except for one DB. When they were trying to start the recovery process from 26th of August, RMAN was requesting the control file from 9th of June 2017 and went back to 30th of September 2016. At the end they started the recovery from September inc0 and it completed successfully. However, I want to understand why RMAN and NetWorker was not communicating properly.

Why I thought it is a strange behavior?

1. RMAN script they are using completed successful with only changing the date from 26th to September(backup without extended retention)

2. All of the savesets are displayed properly when you are using mminfo, in the tape gui, in media tab as well. Everything is listed properly, it is shown as existing. When I am checking each tape displayed in mminfo and media tab, they are containing the save sets of each listener and control file.

3. All of the save sets are listed as browsable

Script we are using to extend the saveset expiration contains below line:

nsrmm -y -w "+7 days" -e "+7 days" -S %%a

Looking for hints and help. Will be really grateful if I get this solved before next month activities.

Thank you in advance