1x14: Cloudy Donkey Mascots

Heh. If you feel you must. Some things that you will want to make sure that your inotify and rsync script handles (this is the “why syncing is more difficult than it looks” list, and every one of them is something we tripped over and eventually fixed at U1, which is why the prototype of U1 file sync took a week to build and the product took three years):

  1. Have syncing happen between two nodes; take both nodes offline; change the same file on both nodes in different ways; bring both nodes back online; have the sync thing mark the file somehow as in conflict and give me the user a way to resolve that conflict on either machine
  2. Mark ~/stuff as a synced directory. Mount a USB stick full of data at ~/stuff/usb. Wait for the syncer to sync all the files on the USB stick to node 2. Unmount the USB stick. Does the syncer now delete all those files from node 2? It should; they’re gone, after all. But that’s unnecessarily customer-data-destructive. Handle this situation in a sensible way. Alternatively, you may declare that you don’t sync the content of mounted folders: so detect mounted folders accurately, and justify your choice to users.
  3. Make it obvious to a user whether a file that they have just changed is synced to the other node.

All of these are actually important. “Notice that a file has changed and copy it to another node” is about 15% of the problem, which is what I’m trying to tell you.

But that isn’t what @Dave, who was suggesting rsync was talking about, and my suggestion was simply to remove cron from rsync and replace it with inotify. I never suggested that I could whip up a U1/Dropbox replacement in a few hours. I’m not that arrogant. I was just saying that one could make inotify+rsync work better/faster than cron+rsync, which I feel I did indeed prove.

Oh! You were responding to Dave? Then I stand corrected and apologise.

The stuff I listed is precisely why syncing is hard. There are an awful lot of people who lodge exactly the same criticism: “why doesn’t U1 work? It’s just basically a two line shell script!” And it isn’t. As a community we are not good at telling the difference between a proof of concept and a product, and it hurts us a lot with real people.

@sil I wholly agree with you there. Dave said “use cron+rsync” you replied “cron is too slow, I need it as soon as I make changes” to which I added “if cron is too slow, use inotify”. I’d never imply a few lines of shell code could replace U1/Dropbox/whatever else. I could replace some use cases, but even then, only the easy ones. Some of your ‘why syncing is hard’ can be handled with better options to rsync, but not all of them. Specifically the ‘both files changed’ is one I am fairly certain can’t be. The other two can either be done with rsync or some prettyifying wrappers around my script.

So in conclusion, syncing is easy, syncing intelligently, as users expect and giving them good feedback, that’s the hard part!

I don’t know that it’s possible for me to agree with this more vociferously. It’s something I wish more people understood.

–jeremy

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You can go to Digital Ocean, spend $5 a month and set up an Ubuntu VPS, set up a mysql database, install owncloud, and you’re done.

Anyone who’s ever manually installed packages can do it in less than hour, and if you get stuck you can easily reset it to a fresh install.

The question was “why are not more people doing this”. It wasn’t why am I, Stuart, not doing this. My dad is in no way capable of understanding what the hell he’s doing in setting up a Digital Ocean VM.

That’s why I qualified it as anyone who’s manually installed packages.

I would support the opinion of the british guy. (I can’t hear the difference of your voices and i can’t memorize names. It’s a problem. :wink: ) Cloud is meaningless. In Germany, where i come from, EVERYTHING is cloud. Even the wifi, and with wifi they want to say access to the internet, in shopping malls are cloud based. (The german tagline says: free internet)

Maybe it is a german problem. We use englisch words all the time, mostly wrong. :-/ You probably already know we call “cell phones” “Handy”

I think that was Stuart (@sil).

OK. So if you’re in agreement that Owncloud is for techies and the reason more people are using Dropbox instead of Owncloud is because Owncloud is for techies, then fine.

just to pull back frrom the alpha monkey stuff; i had a couple questions that werent answered by the podcast.
1; since one of the advantages of cloud storage is the ability to communicate / share files / backup across the different platforms, i would be interested in more discussion about the best options for that. the assumption was that we are all on linux, but i have friends who arent, what are the best options for that?

2; i gather ubuntu1 has changed, mac has a built in thing but only for mac, what about options other than dropbox? there are many more out there, surely? particularly if dropbox is as insecure as you say (havent used it myself, do have a mega account though). this is really question 1 again.

3; the three fedora distrros discussed were workstation, server, and cloud server? did i hear that correctly? id be interested in that, and how that relates to, whatchacallem, clusters and stuff.

and 4; while i can administer from the shell with good instructions to copy, its not ideal. im really looking for a simple GUI. speaking as an end user for these systems, how easily i can collaberate with friends on other OSs to create, say, a song or a movie together is the sort of practical stuff im wanting to do. one click interface and hip hop might just be the answer…

cheers guys.
al on KXStudio.

Don’t know if this is still relevent, but I logged into Box on my Xperia phone and it told me that I now have 50GB of cloud storage for free, Idk if its forever or just a year or what, but if its just for a year, this is great just for partial time until I get some physical back up space!

SO yeah, currently moving alot of my shiz from Ubuntu one to Box, most photos are backed to G+ and college is on drive, I’m gonna miss Ubuntu One, but I have something, finally!

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