Data Backup and Recovery Discussions

Daily Snapshots - Previous Snapshot Grows When Deleting Snapshot Before

RedHatcc

Hi. I am new to NetApp, so please excuse the probably simple question. When I log into our SVM and run the following: 

snapshot show volNameHere

I get the list of the snapshots. This is a very inactive volume, so snapshots are very low in size (about 1MB). However when I run the following command to delete the snapshot:

snapshot delete -volume volumeNameHere -snapshot snapshotNameHere

It removes the snapshot, however it makes the snapshot before it grow to almost its same size. 

 

My question is how are these snapshots linked so when I delete say the one from Friday, the snapshot from Thursday takes its size? Thanks in advance!

1 REPLY 1

GrumpyOldMen

When you don't have an active filesystem, you mean not a lot of data is changed in between taking snapshots. Data changes within the different snapshots are carefully monitored by WAFL. When you delete a snapshot, WAFL will go through it's file system and only those blocks not used anymore by the other snapshots will be deleted. So in your case, not a lot of space is freed.

 

As you are a newbee it's important to understand how the snapshotting is working within WAFL. This is different then other vendors are doing snapshotting!!! Please have a look at following links.

 

http://reyansh-netapp.blogspot.be/2013/04/normal-0-false-false-false-en-us-x-none_20.html

https://www.eigenmagic.com/2009/10/17/why-netapp-snapshots-are-awesome/

http://doc.callmematthi.eu/static/webArticles/NetApp%20-%20SnapShot.pdf

 

Announcements
NetApp on Discord Image

We're on Discord, are you?

Live Chat, Watch Parties, and More!

Explore Banner

Meet Explore, NetApp’s digital sales platform

Engage digitally throughout the sales process, from product discovery to configuration, and handle all your post-purchase needs.

NetApp Insights to Action
I2A Banner
Public