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What I Would Do If I Ran Tarsnap

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801 points tnorthcutt | 2 comments | 03 Apr 14 16:33 UTC | HN request time: 0.567s | source
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acabal ◴[03 Apr 14 18:42 UTC] No.7525065[source]▶
Hit the nail on the head with the pricing model. I really want a backup solution like Tarsnap that encrypts my data client-side and has an OSS client. I'm even fine with it being a Unixy command-line tool. But I have almost 1TB--a lifetime, so far--of pictures and music that I want backed up. I have literally no idea how much that would cost with Tarsnap, and it could be as high as hundreds per month. There's no way to find out until the bill comes. So I'm just not going to bother.

If cperciva wants to keep metered pricing, maybe offering a free 3-day trial or something so users can get an idea of how much their particular backup situation would cost before committing would be a good idea.

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e12e ◴[03 Apr 14 19:30 UTC] No.7525570[source]▶
If you have ~1TB of free space, just create a regular tar archive of your data and compress it -- maybe factor in another 10% for dedup (as seen anecdotally by others with large image collections -- this assumes you have raw images+jpegs -- for just jpegs, maybe nothing). Should be (bounded by) 500 USD first month (storage and upload), and 250 USD/Month after that (and ~250 USD to restore).

I'm not sure what's difficult with these calculations?

The dedup (as I understand it) is mostly relevant for incremental backups "adding up" -- so that you can (mostly) run weekly backups without worrying too much about storage cost ballooning out of control.

Note: I'm not affiliated with tarsnap, nor am I a customer -- partly because I'm in a similar position: The data (emails etc) that I can afford to backup in a similar fashion to tarsnap (I use backupninja as a front-end for duplicity) is almost trivial to backup -- the rest (photos, media) I cannot currently afford to backup to the cloud (nor do I have the upstream bandwidth for it).

replies(2): >>7526154 #>>7527421 #
beagle3 ◴[03 Apr 14 20:13 UTC] No.7526154[source]▶
I am not sure how tarsnap dedups, but you could use apenwarr's amazing "bup" to create a dedupped, compressed backup and get a good idea of the size. But at those prices ...

An external, USB powered, 5400RPM 1TB drive can be bought for $60 last I checked. An online backup service is nice to have, but for $250/month, you could buy a new 1TB disk every week, format it with TrueCrypt, copy your stuff to it, and email it to a random acquaintance/family member (or a known wrong address in Hawaii, so it comes back to you with "wrong address" a few weeks later). It's not as convenient as tarsnap, but way more resilient, not to mention that downloading 1TB back is going to take more than mailing the disk back to you -- or in most cases, taking a return flight to retrieve the disk yourself.

replies(1): >>7528328 #
1. e12e ◴[04 Apr 14 00:43 UTC] No.7528328[source]▶
> It's not as convenient as tarsnap, but way more resilient

I'm not so sure about that. In either case loosing your encryption keys is a single point of failure, but tarsnap is backed by regular s3, so it should take a pretty cataclysmic event for the data to disappear -- contrast that with dropping your hd 1 meter and loosing the data.

I don't expect to have a hopelessly slow and asymmetrical 10-20/1-2 mbs Internet connection forever, so at some point personal backup to the cloud is likely to become more viable (technically I could get ~gps upload at my university right now). The only remaining obstacle would be price -- and while backing up servers via tarsnap sounds great, if all you want is off-site ~1TB storage with the bandwidth to use it you could just get a dedicated server somewhere. Not as redundant, but assuming you have on-site backup on disk, and a live copy on your server, you'd have to be pretty unlucky to loose any data.

FWIW I don't think tarsnap aims to be a personal backup solution (for multimedia) -- and for now neither is S3/glacier. If it were, there'd be no reason for Backblaze to have their storage pods.

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2. beagle3 ◴[04 Apr 14 07:43 UTC] No.7529878[source]▶
> contrast that with dropping your hd 1 meter and loosing the data.

Note that tarsnap prices are comparable to 1 new drive per week. After a year, you'll have 52 fully independent snapshots. If the 4 latest ones fall from 1m height, you still have 48 copies (losing most recent month, but having access to all of last year).

And it doesn't take a cataclysmic event - if Colin can't pay amazon e.g. Because the Canadian FBI might have a gag order instructing him to back door he service ... Or else ... I know he can't, but I am not sure that will stop them from disrupting the service. Same goes for any cloud backup, by the way.