Onboard Data Management ( Yes, I'm a Geek )

[schoonerdog]

Just thought I'd share, been thinking about this a while, we have lot's of precious data, pictures and videos of the kids being the most important. But also tax records, work files, and other things. We need to save the information in a way that's protected and accessible and uses little power.

So this is the plan

For our data itself, it will be protected on a synology ds 411 slim NAS device. It uses about 1/2 to 1/4 the power of a laptop, and would be used for storing the data and playing music, books on tape, etc. All laptops would look to it for any data. It has a built in media server for just that. It will have a couple large 1 TB 2.5 inch drives in RAID 1 (mirrored) to protect against failure of one drive and anand it uses natively 12volts!!!! I'd also send yet another disk offsite (after mirrored) to a relatives for safe keeping. Probably have it mailed back and forth once every 6 months or so. Power consumption is 16 watts and I'd assume it would be on a couple hours at least everyday. Another advantage is I can reimage the laptops when having any software issues and bring them back to a known good state without fear of data loss. I can also take the laptops to internet cafes without worry of data loss.

For just regular data access, such as browsing pictures, reading documents, reading email, browing the web when available we'd have a Dell IM 1018-4034 CLB Review – Atom N455 Netbook which uses just 5 watts. Possibly chart plotting, though I'm not sure. I'm assuming the vast majority of our work would be done with that. Perhaps an hour or two each day.

Then for more serious stuff and movies, we'd have a 17" Dell Studio which uses around 50 watts or so. I'm guessing an hour every other day or so.

[dacust]

That sounds like a valid approach to me.

I'm thinking a different way. I don't think it's better than yours, just different.

I'm planning to build 3-4 carputer type 12v computers with Linux and all open source.. Then just copy data from one to the others. I might loose the last few hours worth of data, but not much. But I'll have totally redundant computers. Gets a little trickier if I use more than one at a time...

Might write my own script to replicate tracks, etc. to the other machines on a schedule. Could even be every 5 minutes.

But, who knows, I might opt for a NAS in addition. I was surprised to see you can get the one you mentioned for about $300.

-dan

[schoonerdog]

depends on power needs for the computer versus nas. the NAS uses a lot less power, so it will be much lighter electric load. Most of the reason we have the laptop on is for things like music. Also, most OS need to be reimaged every so often to reoptimize them. By removing the data, the laptops become solely for viewing rather than storing data. The problem with the data copy technique (I do that now) is that keeping the data synchronized takes a long time, and really draws a lot on the laptop resources. Everything crawls during a sync and doing incremental synchronizations would still require walking the entire file system.

[dacust]

Originally Posted by schoonerdog

depends on power needs for the computer versus nas. the NAS uses a lot less power, so it will be much lighter electric load. Most of the reason we have the laptop on is for things like music. Also, most OS need to be reimaged every so often to reoptimize them. By removing the data, the laptops become solely for viewing rather than storing data. The problem with the data copy technique (I do that now) is that keeping the data synchronized takes a long time, and really draws a lot on the laptop resources. Everything crawls during a sync and doing incremental synchronizations would still require walking the entire file system.

Yep. But I was not planning on full, or even incremental sync. I was planning on just writing a script to only sync routes, tracks, log entries, etc.

Any syncing of charts, etc. would be at load time which would most likely be while on shore power.

Also, I'm on a stickpot and got lots of power.

-dan

[offline]

For your linux cluster use a script like POUND to create a reverse proxy for your network. That way all the "Carputers" act like one machine.

Originally Posted by dacust

That sounds like a valid approach to me.

I'm thinking a different way. I don't think it's better than yours, just different.

I'm planning to build 3-4 carputer type 12v computers with Linux and all open source.. Then just copy data from one to the others. I might loose the last few hours worth of data, but not much. But I'll have totally redundant computers. Gets a little trickier if I use more than one at a time...

Might write my own script to replicate tracks, etc. to the other machines on a schedule. Could even be every 5 minutes.

But, who knows, I might opt for a NAS in addition. I was surprised to see you can get the one you mentioned for about $300.

-dan

[Captain Bill]

Schoonerdog,
Your plan sounds fairly good, but you should backup your important files to some type of non-volitile media, that is one that does not require electricity to store. I suggest a blu-ray writer if you are planning to store lots of photos and video. Every thing that you have in your current plan is subject to the same types of failures and everything that is likely to take out one of your mirrored drives can also take out the other. I don't know where you plan on mounting the NAS in your boat, but put it somewhere that isn't subject to large G forces if you get into a pounding situation. Laptop drives for the most part have self parking heads with a G sensor for drop protection, so consider this when you choose your drives. The sensor activates on 0 G (when the laptop is dropped or your boat falls off a wave) and retracts the heads so that your media is not damaged. Desktop drives do not usually have this feature and sudden G forces (when the boat slams into the trough of the wave it just fell of of) can destroy both the heads and the media. I used to ship drives around the world and about 1 in 10 arrived broken, even when packed very well, so I would expect that you will have some loss shipping drives. I never quite understood why shipping drives after they had been used had a higher failure rate than new drives coming from the vendor, but they did. We even used original packing.

It's much better to ship non-volitile disks such as DVD and Blu-ray. They are much less subject to damage and are easy and cheap to replace. They are also much cheaper to ship. They will survive just about anything a boat can throw at them, moisture, power surges, lightning strikes, high Gs, salt air, even immersion.

That's my 2 cents, change welcome.

[dacust]

Originally Posted by offline

For your linux cluster use a script like POUND to create a reverse proxy for your network. That way all the "Carputers" act like one machine.

Thanks. I'll check that out. However, with just a quick glance, it looks like it is only a http load balancer. If everything was web based, that would be way cool. But maybe I am missing something? I am a Linux newbie. Well, I'm a system admin and do a little scripting, but my knowledge is in a very narrow scope. I am not familiar with all the packages and capabilities. Now if we were building an AS/400 nav system...

I think that since most of the time I'll be running a single application, that's not gonna help. It also won't do the replication.

I don't want to get too complicated, so load balancing and total system replication are out, I think. I might be convinced otherwise, but probably not.

The main thing I need is for the nav software, charts and routes to be available from more than one source. And for me, since all of it will be free software, complete redundant systems sounds good.

-dan

[idpnd]

Personally, I do occasional backups to an external hdd that's not permanently attached to the pc or electric system (surge risk), important documents are synced to the Internet via dropbox. I would certainly want my data OFF the boat