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Creating Retention and Snapshots

[ Edited ]

We have about 10 or so Volumes which contain a single LUN each, where each LUN is mounted on a Windows 2003/8 server. Up until now, we have been taking consistent OS snapshots via a scheduled task that was configured on each server that ran the command "sdcli snap create [snapshotName]. This task would run a few times a day, generally about every 3-4 hours from 7AM - 11PM. Additionally, we would have another scheduled task which would run once a week giving the snapshot a name of xx_weekly_xx. We would then manually once a week delete all the daily (hourly) snapshots taken before the weekly snapshot, keeping a single weekly snapshot for each week.


We have been looking for ways to automate this process. We first thought of using OSSV, but OSSV doesn't support combining hourly and daily snapshots, in which case we would need to store duplicate sets of the data being backed up. Then we stepped back and though about using SnapCreator.

Questions:

  1. I installed and tested taking snapshots with SnapCreator but I don't see any way in the scheduler to allow for multiple snapshots throughout the day. It looks like using the cron scheduler is the only option? I found this sample schedule: 0 0 9-23/3 * * ?
  2. I see that you are required to enter in the Snapshot Retention count/number, but on the other hand the retention time is optional. The popup in the Age box states: "if configured, Snapshots will only be deleted if there are more than defined in Snapshot Retentions and if they are older than retention age". We don't really care about a specific number of snapshots, but rather we are interested in keeping all the snapshots within a specific interval (a week). In order to do this, what do I have to do?
  3. I see there are retention time of type "hourly,daily,weekly,monthly". How do I get the above cycle, whereby I can run a daily backup multiple times a day, and also a weekly backup, and what values do I put for each in the fields for question 2. How do I schedule this?

Thanks,

Reuv

Re: Creating Retention and Snapshots

Hello Reuv,

Please find the answers below.

I installed and tested taking snapshots with SnapCreator but I don't see any way in the scheduler to allow for multiple snapshots throughout the day. It looks like using the cron scheduler is the only option? I found this sample schedule: 0 0 9-23/3 * * ?

While you can use cron scheduler also, the intended procedure is to create multiple scheudles throughout the day. (one at a time). This is a serial activity. (like create one job at 9am and repeat daily, one job at 10am repeat daily etc)

2) I see that you are required to enter in the Snapshot Retention count/number, but on the other hand the retention time is optional. The popup in the Age box states: "if configured, Snapshots will only be deleted if there are more than defined in Snapshot Retentions and if they are older than retention age". We don't really care about a specific number of snapshots, but rather we are interested in keeping all the snapshots within a specific interval (a week). In order to do this, what do I have to do?

Snap Creator Policies

A policy defines the number of Snapshot copies that you want to keep and the Snapshot copy age.

Snap Creator policies are user-defined Snapshot copy retentions that apply to Snapshot copies on

primary storage and SnapVault Snapshot copies on secondary storage.

You must define at least one policy in the NTAP_SNAPSHOT_RETENTIONS configuration

parameter. For SnapVault, you can associate the same policy with different SnapVault retention.

For example, if you want to create daily Snapshot copies and retain them for seven days on primary

storage and one month on secondary storage, use the following options:

NTAP_SNAPSHOT_RETENTIONS=daily:7

NTAP_SNAPVAULT_RETENTIONS=daily:28

You can also specify the minimum age of a Snapshot copy (in days) to ensure that Snapshot copies

are deleted only if they are older than the minimum age, regardless of how many Snapshot copies

exist in a given volume. Using the preceding example of seven days for Snapshot copies and one

month for SnapVault Snapshot copies, use the following options:

NTAP_SNAPSHOT_RETENTION_AGE=7

NTAP_SNAPVAULT_RETENTION_AGE=28

Additionally, you can specify the Snapshot copy deletion by age only using the following option:

NTAP_SNAPSHOT_DELETE_BY_AGE_ONLY=Y

Note: Although you can define multiple policies, Snap Creator can run only one policy at a time.

The maximum age value is a global parameter and it applies to all the policies. To configure an

additional weekly policy, define it and then call it in Snap Creator once a week using Cron or task

manager with SNAP_TYPE set to Weekly.

3. I see there are retention time of type "hourly,daily,weekly,monthly". How do I get the above cycle, whereby I can run a daily backup multiple times a day, and also a weekly backup, and what values do I put for each in the fields for question 2. How do I schedule this?

snap creator can run only one policy at a time. Hence the solution is to create multiple scheduled jobs with each policy type. The key is to ensure that the jobs are spaced with enough time to allow application quiesce/un-quiesce if any

Re: Creating Retention and Snapshots

Hi,

 

eventhough snapcentyer is still maturing, we could use thepolicies to create multiple schedules. i have daily data backup schedule and 4 hour Log backup for SQL, daily backup and 2 hour log backup schedule for oracle.

 

Regards,

Mani