NETGEAR is aware of a growing number of phone and online scams. To learn how to stay safe click here.
Forum Discussion
Solved
Snapshots set to hourly - some are missing #26605970
I’m experimenting with an RN204 and OS 6.4.2. Long term my employer would not use that but may buy an RN516 or RN716. The RN204 is just an inexpensive way to test out the features and functionality o...
This issue got bumped up a support tier. I have been working with them and here is what is going on: if disk spindown is enabled, hourly snapshots can be missed. If spindown is not enabled, hourly snapshots are taken each hour as expected. This has been confirmed for OS 6.4.2 and 6.5.0 beta on an RN204. It may apply to other models, I'm not sure. A problem report was logged into engineering to fix the issue.
I want to thank support, which has been excellent, and you folks for your efforts. From my point of view this thread is resolved.
The file was copied using Windows explorer. Ctrl-C and CTRL-V. I'll rerun the experiment to confirm the results.
Reading into your answer, it sounds like no snapshot if no files changed is intended operation?
A missed snapshot is important to us. Our users recover files from snapshot on our current system many times a month. We have CAD folks who do design all day and who would lose an hour of work if they have to go back an extra hour.
TullyNYGuy wrote:
Reading into your answer, it sounds like no snapshot if no files changed is intended operation?
My smart snapshots were previously set to daily, which seem to be always created - I'm not sure on hourly.
However, the 6.5.0 has a "custom snapshot" feature which I am now using. That includes a checkbox for "Only take snapshots with changes". You can also set retention (either in days/months or number of retention). They are not "thinned" over time either. It sounds to me like the custom snapshots might be of interest to you.
I reran the experiment where I copied an existing file using windows explorer within a share: Select the file. Ctrl-C and then Ctrl-V. No other changes occurred within the files of the share. The hourly snapshot was not taken.
My guess is that there is a bug or I don't understand the functionality. I think a snapshot should have been taken due to the additional file.
That file was an excel spreadsheet. So I modified the copy by adding some text to a cell and then saved it. Still no snapshot taken on the hour. That makes me nervous.
Then I did the same procedure with an ascii text file. Copy without any modification = no snapshot on the hour. Then I modified the copy and saved it. I got a snapshot on the hour.
Bottom line, I don't understand how it determines when to take an hourly snapshot. I would have thought if a new file appeared that would trigger a snapshot on the hour. Certainly any modification to the copy should trigger a snapshot. So I'm going to call it a bug and see if support agrees.
In practice, in our environment the share will see hundreds of files changing per hour. So I don't expect any missed snapshots. If there are, then a ReadyNAS is not for us.
The Custom Snapshot Management from 6.5.0 Beta 1 brings the option to "only take snapshots with changes". As far as I know this wasn't part of any hourly/daily/weekly/monthly snapshotting on 6.4.2 and before. But maybe it was introduced to reduce the number of snapshots as 48 hourly snapshots multiplied by the number of shares you're using that one, can become a LOT of snapshots.
Regardless of this "only take snapshots with changes", copy and pasting the same file generates a new file, not a hardlink. The data may be the same but the file itself is different. As there is no deduplication capabilities on the ReadyNAS, it doesn't sound like BTRFS would know it's the "same" file and not take a snapshot (also because it's basically not the same file as it wasn't deduped).
I'll do some tests on my NAS to see if I have the same behavior.
If that helps, on my RN312 6.5.0 Beta 1, all hourly snapshots are created regardless of new data or not (on standard Smart Snapshot Management).
NETGEAR Academy
Boost your skills with the Netgear Academy - Get trained, certified and stay ahead with the latest Netgear technology!
Join Us!
