Protection Manager not deleting snapshots from the primary

[michaeldparker]

Hi All,

I have snapcreator 3.6 integrated with PM to handle transferring my backups to a test array.  PM is deleting the backups off the backup array location per the policy configured on the dataset, but it is not deleting the primary backups.  By doing the dfpm backup list command, I see the snapcreator backups are registered with PM and have the correct retention policy of daily.  I have my policy in PM set to only retain two days of daily's, but it does not delete any of them.  Anybody have any ideas where to start looking to resolve this problem?

Thanks

Michael

[michaeldparker]

Here is the output of my dfpm backup list command:

:\>dfpm backup list 51419

ackup Id Backup Version        Retention Type Retention Duration (in seconds)   Node Name            Description                         Properties(Name=Value)

-------- --------------------- -------------- --------------------------------- -------------------- ----------------------------------- -------------------------

   29765 14 Jan 2013 10:19:13  daily          259200                            Backup               NetApp Snap Creator Framework 3.6.0 Backup

   29764 14 Jan 2013 10:19:13  daily          172800                            Primary data         NetApp Snap Creator Framework 3.6.0 Backup

   29463 10 Jan 2013 15:30:17  daily          259200                            Backup               NetApp Snap Creator Framework 3.6.0 Backup

   29462 10 Jan 2013 15:30:17  daily          172800                            Primary data         NetApp Snap Creator Framework 3.6.0 Backup

   29378 09 Jan 2013 15:30:20  daily          259200                            Backup               NetApp Snap Creator Framework 3.6.0 Backup

   29377 09 Jan 2013 15:30:20  daily          172800                            Primary data         NetApp Snap Creator Framework 3.6.0 Backup

   29332 09 Jan 2013 06:00:19  daily          172800                            Primary data         NetApp Snap Creator Framework 3.6.0 Backup

   29243 08 Jan 2013 06:00:20  daily          172800                            Primary data         NetApp Snap Creator Framework 3.6.0 Backup

As you can see, I have backups on primary from the 8th, but only the 9th on the backup side. 

Here is the contents of the policy associated with the dataset:

H:\>dfpm policy node get Snapcreator_DB2_Backup_Test_Env

Node Id:                    1

Node Name:                  Primary data

Hourly Retention Count:     2

Hourly Retention Duration:  0

Daily Retention Count:      2

Daily Retention Duration:   172800

Weekly Retention Count:     1

Weekly Retention Duration:  0

Monthly Retention Count:    0

Monthly Retention Duration: 0

Backup Script Path:

Backup Script Run As:

Failover Script Path:

Failover Script Run As:

Snapshot Schedule Id:       0

Snapshot Schedule Name:

Warning Lag Enabled:        Yes

Warning Lag Threshold:      129600

Error Lag Enabled:          Yes

Error Lag Threshold:        172800

Node Id:                    2

Node Name:                  Backup

Hourly Retention Count:     0

Hourly Retention Duration:  0

Daily Retention Count:      2

Daily Retention Duration:   259200

Weekly Retention Count:     2

Weekly Retention Duration:  0

Monthly Retention Count:    1

Monthly Retention Duration: 0

[kryan · Accepted solution]

Hi Michael,

SnapCreator integrates with DFM/UM in a manner that allows it to control the primary side retention instead of DFM/UM.

The snapshot retention should be defined in the SC policy according to the SC 3.6 Installation and Administration Guide and then set in the SC config file.

https://library.netapp.com/ecm/ecm_get_file/ECMP1133886

[michaeldparker]

Thanks for the quick reply.  Yes, I had known that SC could manage the primary side backups, but I have some other SC datasets configured where the retention is managed by PM for primary and backup sides.  I remember because I was getting errors in PM because it'd try to remove the backups and failed since SC had already cleaned up. I guess since PM is not doing anything on these particular datasets, I could just use SC to manage the retention for the primary side.  If I did that though, I'd like for SC to manage retention on the backup side just for ease of troubleshooting.  How would I tell PM not to mange the retention?  Do I just set it to a big number or is there a better way?

Thanks

[michaeldparker]

Ok, I got SC to manage the primary and left PM managing the destination.  Seems to work fine that way so we'll call it good enough.

Thanks

[kryan]

Hi Michael,

The design is such that that applications should control the primary backup retention (backups it creates and then registers against the primary node of the dataset) and DFM/UM controls the secondary backup retention (backups that it creates).

There is no way I am aware of to modify this behavior except through unintentionally designed behavior occurring in versions of SMO/SMSAP prior to 3.3.  And even though the backups in these cases can all be deleted by DFM/UM, it is not the design and leads to errors in the applications when they look for the backups they created and expect to be available.

Also of note, SC 3.6 can handle its own vaults, without the need for integration with DFM/UM, and thus can control the retention on both sides of the relationship if desired.

Kevin

[michaeldparker]

Thank you Kevin for your detailed answers. Now I understand why my sc data sets are working the way they are. They were created with sc 3.3. My latest ones I was trying to get working the same way were created with sc 3.6. I changed sc to handle the deletion of the backups and everything is working perfectly. Thanks!

Sent from my iPhone

[adaikkap]

Hi,

     As kevin said, the design is that, SnapManager manage the retention of primary snapshots. But SnapCreator being a frame work allow you to customize whether SC or PM to delete the primary snapshot. I am attaching a image where by checking the option " Protection Manager Responsible for deleting Snapshot on Primary" the retention of primary snapshots are manged by PM and not SC.

Regards

adai

[kryan]

Thanks for the screen cap Adai.  I looked for this information in the guide and found it on pages 201-202:

==================================

Snapshot copy and Protection Manager update

When using Snap Creator to create a Snapshot copy, register the Snapshot copy with Protection Manager and then use Protection Manager to manage SnapVault or SnapMirror.

NTAP_SNAPSHOT_NODELETE Y

Note: Both Operations Manager and Protection Manager are required. Additionally, you must configure a dataset created by Snap Creator within Protection Manager and create a schedule for

that dataset (secondary). Snap Creator or Protection Manager can delete primary Snapshot copies. Protection Manager manages all secondary Snapshot copies and their retentions.

==================================

I also found this info not in the IAG:

In the config wizard, a check box is displayed where you can select "Protection Manager responsible for deleting snapshots on primary" and if it is selected the dataset is created with

is-application-managing-primary-backup-retention = false and NTAP_SNAPSHOT_NODELETE is set to Y.

If it is not selected  then the dataset flag is-application-managing-primary-backup-retention = true and NTAP_SNAPSHOT_NODELETE is set to N.

What I do not know is what happens if you have set the dataset flag to false and then later set the config parameter to N.  It seems to me that might lead to a build up of the primary snapshots.