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Re:DigitalOcean not destroying droplets securely, data is co... by raiyu on Sunday March 30, 2014 @10:54PM (#7499299)
Hi Folks,

Just wanted to clarify the issue for anyone who didn't have the time to read the full gist.

When we first started DigitalOcean we occasionally received tickets from customers about recovering a droplet that they had destroyed. Unfortunately when a droplet was destroyed it was gone from the system and it wasn't possible to recover. To help our customers we decided that it was a good idea to take a temporary snapshot of the droplet after the destroy was issued that would automatically expire. This way if someone mistakenly destroyed a droplet they could still recreate it.

This proved to be a lifesaver for many customers of DigitalOcean when a third party company that provided a provisioning service that integrated with DO, AWS, Rackspace, etc. was compromised and the attacker issued a delete to all customers and all instances. Because this mechanism was in place we were able to recover almost everyone's droplets.

We ran into an issue with securely scrubbing data which was publicized on HN and we implemented a fix immediately with a scrub flag. Unfortunately we made a mistaken and made the default setting false. Most customers often click the default, and I myself do the same thing, since I assume that the default is the best course of action and this led to this issue resurfacing. This also was posted to HN and we immediately decided that the default behavior should be to scrub.

Prior to this when a customer selected scrub securely because they were taking two actions, issuing a destroy, and setting a flag, it was safe to assume that they indeed want the data completely destroyed. However when we had to reverse the default we were left in a situation where the default would not create a temporary snapshot if we used the secure destroy flag as the indicator for whether or not a temporary snapshot should be created.

Since we've implemented the temporary snapshot feature we have had 1154 droplets that have been restored after a destroy from different 752 customers.

That's 752 customers that were elated to find out that they could recover a droplet that was mistakenly destroyed so obviously this is a very beneficial feature since each time one of those customers recovered a droplet it was a huge win for them.

We assumed that since the temporary snapshots are automatically destroyed this would not be an issue. In fact in the control panel we provided an additional feature which would make the snapshot permanent otherwise that snapshot is deleted.

I think the issue that is brought up here is definitely worth a discussion and we treat security very highly. Since we had the prior HN post regarding changing our default behavior we have been working behind the scenes to ensure that would be the default behavior so that the scrub flag could be removed entirely and that all destroys regardless of how they would be issued would be secure.

That behind the scenes work is almost entirely done so this discussion of the temporary snapshot is great because it allows us to revisit this issue once again.

We have not had any other customer complaints that during a secure destroy the droplet and the backups and the snapshots were not immediately destroyed. So it was great to engage in a conversation with the customer to understand their view on how they wanted these commands to functions.

We'll be engaging with engineering tomorrow to see if it's time for us to begin to phase out the scrub data flag and instead perhaps open up a new flag which would create a temporary snapshot.

For the UX/UI of the control panel we would make the default behavior of the destroy create a temporary snapshot and we would have to discuss to see if the API should behave the same way.

Often API customers are creating and destroying many servers so it may be safe to assume that they do not want a temporary snapshot, though having default behaviors differ between the control panel and the API is generally not a good idea.

I think in general this highlights an issue that all startups deal with. That is as the product grows and matures and as features are added there are often unintended cascading consequences.

In this case we have done our best to do right by the largest number of customers to ensure that data is safely and securely destroyed while still providing a default behavior that would protect customers against accidental destroys whether they be self-initiated or otherwise.

If anyone has any questions regarding this issue or anything else always please feel free to email me directly, my first name, Moisey, at DO (expand that) . com.

Thanks, Moisey Cofounder DigitalOcean

Re:DigitalOcean not destroying droplets securely, data is co... by gingerlime on Monday March 31, 2014 @04:05AM (#7500248)
Availability is a core part of Security (not just Confidentiality or Integrity). In that respect, I think DO is doing the right thing - they eventually scrub all data, but leave a small window to recover from mistakes.

Of course, it depends on the use-case and customer priorities, but in my opinion, availability is a much bigger concern for most DO customers than confidentiality. If customers are deeply concerned about the latter, I would say they are less likely to choose a virtual platform in the first place.

I think this could be corrected with a small note (backup data will be scrubbed within 24 hours. If you wish to remove this data sooner, click here).

Having experienced making a mistake and removing the wrong virtual host (albeit on Linode), I really appreciate the fact that it could be recovered. And yes, I have external backups and could have recovered it otherwise, but it was much easier to have an 'undo destroy virtual host' button (so to speak) than to kick off my restore process.

I hope Digital Ocean and other cloud providers don't change the default behaviour. It will hurt many more customers than it would help in my opinion.

Re:DigitalOcean not destroying droplets securely, data is co... by Fuxy on Monday March 31, 2014 @05:40AM (#7500494)
I agree with you temp images are good however that check box text is not phrased right it should either say that it takes up to 48h to happen or specify that it only happens on the hypervisor and give you the option to not make temporary backups as well.
Re:DigitalOcean not destroying droplets securely, data is co... by dkural on Sunday March 30, 2014 @11:01PM (#7499321)
Your approach seems very sensible and the data you provide is in support of this. I do hope you stick with this, and more importantly, your data drive meta-methodology, and not let an HN post who don't face the use cases etc. drive you to abandon this.
Re:DigitalOcean not destroying droplets securely, data is co... by raiyu on Sunday March 30, 2014 @11:11PM (#7499360)
We love to hear feedback from customers because it allows us to refine the product. From our internal metrics we know that providing an automatic snapshot recovery function is essential given the number of times its been implemented but we can also understand this customers issue with data being destroyed.

The data is destroyed securely, but not as immediately as they would have liked since the default behavior is to preserve a snapshot until it automatically expires.

These discussions are great for us because they allow us to refine the user experience and ensure that we can provide a great service. As we've been doing a tremendous amount of work on the backend code this is a great time for this customers concerns to be discussed as we are knee deep in large rewrites at the moment and its the perfect time to address this, rather than deploy to production and then have to go back and retool.

Given that we've been working on the secure destroy all the time having that be an option doesn't make sense and instead we can use that UX/UI real-estate to expose the temporary snapshot issue but again would love to hear more feedback on whether that's necessary.

We would of course love to please every customer but then we would have a platform with 1,000 features so sometimes you have to politely decline a request because it doesn't fit in with the general use cases, but it doesn't mean that we shouldn't engage in a discussion as that is always helpful.

Even if action isn't immediately taken it often leads to us asking numerous questions that are always great that can lead to new product and feature ideas that may not be tied to the original question in mind but still can move the product forward in other areas.

Thanks!

Re:DigitalOcean not destroying droplets securely, data is co... by lscott3 on Monday March 31, 2014 @09:53AM (#7501426)
I agree. I also think that the poster could have talked with a DO rep. before making this public. It seems like the intention was to "expose" DO. I could be wrong though.
Re:DigitalOcean not destroying droplets securely, data is co... by atdt on Monday March 31, 2014 @12:32AM (#7499642)
Something doesn't add up. The user who wrote the report did not request that the destroyed droplet be recovered. The existence of lingering data was disclosed by traces which appeared in a brand new droplet. The only reason I can come up with for why that would ever happen is that you are re-using droplets, perhaps because erasing and resetting a few files is cheaper and faster than provisioning a brand new instance. If this is indeed the case, then what you are suggesting -- namely, that what looks like sloppiness is in fact conscious, customer-driven product design -- is completely false, because it means that the droplet recovery feature is available only in those cases where the customer did not create a new droplet after destroying the droplet she would now like to recover. I guess that this is why you were "able to recover almost everyone's droplets" after an attack, but not everyone's. The "temporary snapshot" feature is not actually a feature, or even a "mechanism" -- it's a bug, just one with a side-effect is occasionally positive.
Re:DigitalOcean not destroying droplets securely, data is co... by nixgeek on Monday March 31, 2014 @12:39AM (#7499657)
Sorry that's on me for not explaining better:

I created a droplet and then destroyed it with the 'Scrub Data' checkbox enabled, and was surprised when I noticed it had been turned into a "temporary snapshot" rather than eliminated entirely in a secure, irrecoverable manner as the text around that UI element would have suggested.

I then went ahead, to prove a point, in restoring said snapshot onto an instance called 'test' and what you are seeing in terms of lingering data is from 'test' as very primitive proof that the snapshot did indeed occur and 'Scrub Data' doesn't behave how I think it should.

tl;dr - raiyu is being perfectly forthcoming and DigitalOcean is not reusing droplets to avoid erase/reset, we're just quibbling over the semantics of whether the 'Scrub Data' box should have a safety net or not, and whether the presence of a safety net could be deemed a security issue.

Re:DigitalOcean not destroying droplets securely, data is co... by bsaul on Monday March 31, 2014 @03:40AM (#7500176)
I read the blog quickly and didn't understand that you restored the snapshot either. I think that's something you should highlight better, because it completely diminish the level of the issue.
Re:DigitalOcean not destroying droplets securely, data is co... by henryaj on Monday March 31, 2014 @04:07AM (#7500254)
Agreed. It took me a while to figure out and it basically makes your post moot, from what I can tell. I thought you made a brand new droplet and found your old data on it.
Re:DigitalOcean not destroying droplets securely, data is co... by nixgeek on Sunday March 30, 2014 @11:12PM (#7499367)
Moisey - Hat tip definitely due, you've been nothing short of responsive about the concerns raised and I can completely understand what led you down this train of thought, although I continue to think it presents an unwelcome surprise to customers thinking about their data security.

Destroyed should mean destroyed and if the outcome is a UX/UI change to remove the 'Scrub Data' (making it default) box and replace with a 'Temporary Snapshot' box (along with accompanying tooltip for explanation) then I think that would be a perfectly great way to assuage my concerns, and a positive development to the DigitalOcean platform.

Obviously there remains a question of how best to tackle this from an API perspective, perhaps you can consider adding a new parameter to /droplets/:id/destroy along the lines of 'temporary_snapshot' (bool) or similar, with a well-documented default behaviour if not passed in.

Re:DigitalOcean not destroying droplets securely, data is co... by raiyu on Sunday March 30, 2014 @11:17PM (#7499384)
Agreed, this highlights a larger issue that we've been dealing with as we've grown to over 100,000 customers and the platform has evolved.

When you have a singular product with a very narrow focus, say Instagram, it allows you to really strip away everything besides the core functionality.

When building a platform often you start off with something simple and elegant and as the number of customers grow you quickly begin to realize that as a platform you need to provide more customizability than first intended.

With that in mind we've been working with our customer support team to understand what are the most frequently asked questions and began to automate that directly into the support system as well as provide a more relevant and up to date help guide for the platform. Both inside the control panel directly but also searchable.

Of course one of the thoughts was to make all of the help documentation public on github and then also field requests from the community to help rewrite any documentation that wasn't clear.

Sometimes when you are engineering a product you take for granted all of the knowledge that you have and something that is obvious is entirely missed.

So that would be the idea behind asking our community to help us update the documentation since they come in with fresh eyes and can spot things that we can't see because for us it's been a continuous spectrum of development rather than something that we just walked into at some point in time.

Thanks!

Re:DigitalOcean not destroying droplets securely, data is co... by clmorg01 on Monday March 31, 2014 @12:39PM (#7502501)
You mentioned in a comment above an occurrence where someone's DO account was compromised leading to many droplets being trashed but that the account holder was able to recover because of the waiting period. If you add a flag to bypass the temporary snapshot would not this mean the hacker could have succeeded in their attempt to wipe out all the droplets?

I actually prefer the enforced cooling off period for destroying droplets. (As long as the UI/API docs are cleaned up a little to communicate it better.)

Re:DigitalOcean not destroying droplets securely, data is co... by ivan_gammel on Monday March 31, 2014 @08:12AM (#7500895)
Replacing one checkbox with another is not solution, since it will remain optional for customer and thus can easily be missed when submitting the form. For such sensitive topic there must be explicit confirmation of user intents.
Re:DigitalOcean not destroying droplets securely, data is co... by Fuxy on Monday March 31, 2014 @05:27AM (#7500461)
I see where your coming from a lot of people don't seem to understand the meaning of permanently and irrecoverably deleted.

My suggestion is to remove the secure delete flag/option there's little reason not to securely delete things and make the default behavior on both websites and the API as delete with 24h-48h backups.

However add a flag/option that does permanently and irrecoverably delete the droplet without making any backups.

This flag/option should require active input from the user so there are no excuses or misunderstandings once checked it's gone for good.

Re:DigitalOcean not destroying droplets securely, data is co... by axaxs on Monday March 31, 2014 @02:47AM (#7500033)
Semi offtopic... I love your interface and service. However, IPv6 is a requirement and you don't offer it. It's been promised for years now, but you leave your customers in the dark. Either say no, like aws, or yes. Please don't keep dicking with us.
Re:DigitalOcean not destroying droplets securely, data is co... by mnordhoff on Monday March 31, 2014 @06:30AM (#7500596)
There was just some news on that front, actually. There should be an IPv6 beta in Singapore in a few weeks.

http://digitalocean.uservoice.com/forums/136585-digital-ocea...

Re:DigitalOcean not destroying droplets securely, data is co... by duongkai on Tuesday April 01, 2014 @03:50AM (#7506707)
Hope so this is a programming issue.

But I think DigitalOcean is doing the right thing for customers.

Re:DigitalOcean not destroying droplets securely, data is co... by xorgar831 on Monday March 31, 2014 @02:33AM (#7499997)
How did you solve the original performance problem with scrubbing by default?
Re:DigitalOcean not destroying droplets securely, data is co... by d23 on Monday March 31, 2014 @01:06AM (#7499748)
You've responded well -- all you can hope is that people understand.