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Comment Re:tips (Score 1) 695

At a minimum, you need:

  • A fair amount of 14- or 12-gauge wire (wire is expensive... go measure)
    • wire from generator switch breaker to each device
    • wire from generator to generator switch (needs to be underground / outdoors rated)
    • wire from main service to generator switch
    • instructions are generally with generator switch - study hard. Errors can be disastrous
  • A 15A or 20A socket at each power location (fridge, furnace)
  • A manual generator to line switch ($150 or so on Ebay)
  • A generator. I suggest MINIMUM 3500 watts Even though a furnace doesn't pull a lot when running, at the time that the blower starts up, there can be a VERY large startup current. The fridge the same, to a lesser extent.
  • A shed -- you can't put a gas generator indoors, generally speaking - very dangerous
  • I strongly suggest a strong table to mount the generator on for maintenance
  • Some way to bolt the table down, and bolt the generator to the table
  • High temperature exhaust hose for the generator (actually kind of difficult to come by)
  • high-temperature pass through for exhaust to go thru shed wall - hot!

You can get a lot fancier than this, but this will function perfectly as long as you are there to do the switching soon enough after power fails that your building doesn't get too close to pipe-freeze (I wouldn't want to go below 40 degrees f, pipes are often in walls that are cooler than the rest of the house.)

If that won't do, you're looking at an auto-start system with an auto-generator switchover, and the only thing I can tell you about that is prepare your wallet for deep excavation.

Sorry, fyngryz; but your reply needs to be downmodded for "Overkill", and "FUD".

Step 1) Buy a genset. Get 6000 watts or better, if you can afford it. Make sure it has a 220V twist-lock outlet on it, in addition to the usual dual-120V outlets.

Step 2) Buy a nice length of fat extension cable (10AWG or bigger), with a male twist-lock on one end, and a male dryer plug on the other. Your Home Depot or local electrical supplier can make it up for you if you lack the boxcutter-and-screwdriver skills necessary to assemble it.

Step 3) Bring it all home, fill the genset with gas. It will probably hold something like 20 litres (as you're in the States, I'll convert for you: ~5 gallons).

Step 4) Go to your breaker panel, and shut off the MAIN breaker, as well as any baseboard heaters and your hotwater tank. Those will all be 220V breakers (the double kind). Leave all the rest on, if you like. If you have sensitive electronics, feel free to shut off those breakers or unplug the devices- which you've probably already done anyhow, since when your lights went out, there was an accompanying surge which melted all your power bars, right?

Step 5) Plug the large plug into your dryer outlet. Yes, it might be awkward to reach. If you have the money and time, get an electrician to install a 220V dryer outlet on the outside of your house somewhere near where you'd park the genset. Your choice.

Step 6) Start the generator. Once it's running smoothly, plug the twist-lock in. If it stalls out right away, the chances are you forgot to shut off your mains breaker and are trying to feed power back onto the grid.

Step 7) Go inside and enjoy your warm, well-lit household. By being careful, you can use all the major appliances in your house, including your range and oven. If you run out of hot water, lower the rest of your load and turn the tank back on for a while. Just don't try and bake bread while your water tank is on (typical load for a hotwater tank is 3KW). You'll get a feel for it- if the generator bogs down really bad, it means you're overloading it. Back off a bit. Worst thing you can do (provided your extension cable is properly gauged) is stall the genset.

Step 8) In about 8 hours, go outside and feed the genset some more gas.

This response by fyngryz is ludicrous. Even in a professionally-installed backup power system, you never run feeds to each device, you merely use an automatic switch to shunt the mains from the utility to your genset. If you have money to burn, you shell out the $12,000 it costs and have a proper diesel or propane-powered generator installed (you don't need a shed, they come in their own housings these days). It will have an automatic starter so that within 3-5 seconds of the power failing, you'll be on backup.

When I lived in an isolated seaside village in northern Canada, where the power would go out regularly for days at a time, it would take me less than 3 minutes to bundle up, wade through the snow to the woodshed, pull the genset outside, plug in the cord, run it in through the back door to the dryer outlet, and be lights-on and surfing the web again. Backup power is NOT magic or scary or even expensive- you can get a 6KW genset for $500, brand new, add a couple hundred if you're lazy and want electric start.

Comment Re:I'm a tech coordinator for a small district... (Score 1) 1117

I am in almost the same position as this tech coordinator (we have 520 students). We have only had a couple (less than 5, for sure) students who have attempted to circumvent the System. We've had one who figured out that Firefox stores all your passwords in plaintext, and managed to borrow a clueless teacher's laptop long enough to copy the entire list of her login, network, banking, and email passwords (um, hello, now you know why we tell you all the time to LOCK THE SCREEN!). But no, the students AREN'T falling over themselves trying to hack the network or get unrestricted web access. The only time they get creative is if we block apps like iTunes, since that pisses them off.

Besides, our laptop program isn't a tech-training program. We're treating the laptops like tools, like textbooks. Sure, you need to know how to use that tool, but that's not the focus in the classrooms. We leave that for the tech-ed teachers.

Comment Re:Its hard to say... (Score 1) 1117

Our student sign an AUP when they register each year. It's also signed by their parent or guardian. And it's not a legal document, perhaps- but we're not going to charge them with a crime if they violate it; we'll merely take their laptop away for an appropriate amount of time, or impose some other consequence for their actions. Our AUP also says you won't use our network to send porn or spam or conduct business (could be construed to prohibit eBay), yet we only really come down on people who send spam. And they're usually our bosses...*grin*

Comment Re:Why Macbooks? (Score 1) 1117

You have a point- there are a lot better ways the money could be spent. That being said, there are sound pedagogical reasons for using the Macs, particularly with regard to literacy and numeracy. HOWEVER, if our friends at Sun ever get Open Office up to MS Office's specs, a LOT of people will migrate to OSS. The only reason we haven't is that MS Word has features that are used every day by our teachers, that OO lacks. Once those show up, we'll be the first to go to Linux!

The other things Macs have going for them are sturdier hardware and a great (better than Windows) OS. We have never had one come in with a virus or malware; and they can literally take a hell of a beating.

I tell you though- Apple is killing their education (K-12) market in a hurry by pulling stunts like dropping the 12" subnotebooks and killing firewire. When the MSI Wind is available in a 12" format, maybe we'll seriously look into going Hackintosh!

Comment Re:Create a restore point and a data partition (Score 1) 1117

Deepfreeze actually works quite well- it allows you to set a 'thaw' partition that allows users to store files on the local machine, but keeps the c: drive locked down.

That being said, I would never in my wildest dreams think of releasing Windows laptops into the wild of a student body, if I were expected to keep them running. A lab is one thing, but mobile machines? Egad. Especially if they were allowed to take them home and connect them to the wide open cesspit of the unfiltered malwareverse!

Comment Re:You are not alone, others have done the same th (Score 1) 1117

Yeah, thanks for that, buddy! Good thing the government is paying our bandwidth bill...

I think there's a disconnect between what governments want and what is actually required. Too many people are scared of the Big Bad Internet and all those legions of pedophiles and cyberbullies and l33t h4x0rs just waiting to corrupt The Poor Defencless Children. They take the position of "If we protect our children from it, they won't be hurt by it", and "If they can't access it, it won't corrupt them"; which is ironically the exact opposite tact taken with regard to that other topic, Sex Ed. If you tried to tell educators that they should be simply banning sex among children, or that they should segregate schools by sex, you'd be laughed out of town. Yet when it comes to something like the Internet, they attempt to do exactly that.

In our District (SD92 Nisga'a), we apply an absolute minimum amount of filtering. Don't get me wrong- our connection is content-filtered at the gateway in Victoria where our main connection point is- that's because the Province provides all schools with broadband connections, and they use a single gateway for all of us. It's filtered by Websense, which is a pretty stupid company overall, but fortunately, we have our own set of rules, so we're not tied to what everyone else gets. If a site is blocked that we feel is legitimate, we can (and have done) request a removal, and it takes a day or two to kick in.

At a District level, we do zero content filtering. We will occasionally block a website temporarily at the request of an administrator, but at most for a couple days (if, for example, there's a case of bullying that needs to be dealt with). We do watch our squid logs for 'interesting' surfing habits, but in several years, that's only resulted in a couple of reprimands for students.

As for other restrictions, we use Apple's Workgroup manager to help with that, although I have to say, it's probably not the best thing out there. It tends to cause us headaches with mobile users. We restrict what students can install through Workgroup Manager (they get a local account on the machine, but it's very restricted), and teachers can authenticate to allow apps to be installed if needed. We had to kill Bonjour on our networks because there was too much filesharing and chatting going on during classtime- which really comes down to a classroom management issue, not a technical one, but it's easier for teachers to ask for services to be nuked than to change how they run their classrooms. (That being said, most of our teachers are awesome and really do grok the importance of open networks.)

Our students get to take their lappys home at night, and because we use an authenticating proxy for web in our schools, they need to disable their proxies outside the district. Since they can't (limited account), we provide them with Firefox on their machines, and set it for direct connection. That way, Safari uses their Network Prefs proxy, and Firefox lets them straight out. For teachers and admins, we set them up with Locations.

As for customising the laptops, we pretty much let them at it. We spend a lot of time in the summers removing stickers and Sharpie doodles, but allowing the students to personalise their machines actually has given them a higher level of ownership, which results in less willful damage to the machines.

As to the discussions around selling the units when they hit a certain age, we've decided not to go that way. For student machines, because they are almost all using G4 iBooks, we're keeping as many as we can and using them for spare parts as the warranties expire. And honestly, after four years in a high-schooler's hands, those things aren't worth much! The Elementary students are a lot easier on their machines, so those ones last longer. We talked about selling them at, say 4 years, but decided it would be better to keep them for spare parts. While you will only get $200 for a 4-year old 12" iBook, if the screen is good it's worth $600, and the logic board is worth $700 (GSX replacement cost). So that crappy-looking, scratched-up brick is suddenly worth more than we paid for it as spare parts alone.

As for live screen monitoring, we have Apple Remote Desktop for that. Our teachers can use it for helping students or just checking quietly to make sure they are working, but not many do. As techs, we really only use it for troubleshooting- like we have time to babysit! If a laptop is reported stolen, we will check our logs to see if it's online, then we'll try and get an ARD session going to get more data. But Workgroup Manager tells us who's logged into the machine and all that stuff anyhow.

I can go into a lot more detail if there's interest, but I gotta go watch Big Bang Theory now. Obviously the Slashdot traffic wasn't enough to kill my bittorrent session!

Comment Re:No offense... (Score 1) 1117

We use Apple's Workgroup Manager in our district to control user rights on our ibooks and Macbooks. It's "ok", but not "great". Works well for restrictions, but not so well for un-restrictions. For remote monitoring, our teachers have Apple Remote Desktop- similar to VNC, but more feature-rich (and expensive!). For monitoring users' web activities (all we really are told to care about), we have our Squid logs. Students who take their lappys home obviously have to either a) change their proxy settings (which they need admin rights to do, so that's out); or b) run an alternative browser (we set up Firefox with no proxies for this purpose, and they use Safari in-school).
Communications

Submission + - Passive Optical Networks - suggestions?

who's got my nicknam writes: "I have been asked to help with the replacement/upgrade of a community cablevision system in a small, remote village in Northern Canada. The existing coaxial cable plant has to be completely replaced due to corrosion and age; the headend is being replaced because the building it was in burned down. The community wants a modern infrastructure that can be used for television, Internet, and telephony (Triple-play), as well as local access to educational networks (ie, the system will need to support VLAN so customers can access a local LAN in addition to their Internet ISP's gateway).

My research leads me to believe that GPON is going to be the preferred technology, but we are having a hard time sourcing hardware. The actual glass will be easy to source and install (and where I am located, fibre optic cable is cheaper than copper anyways), but we need a reputable vendor for the headend and CPE hardware. It seems a lot of what's being talked about in press releases is still vapourware.

The community consists of about 150 homes in a tight geographical area. There is currently a high-speed microwave link providing an E10 to the local school, as well as another E10 to the local WISP, so bandwidth in and out is fine. Construction on the last 30 kilometres of fibre to reach the village will begin shortly, after which the microwave will be surplussed.

Given the small size of the community, EPON would be a viable alternative, but I am a bit concerned about its limitations regarding HDTV. Maybe that's not an issue though.

Any vendors or geeks out there who'd care to offer advice or pre-sales support on a project like this? I can be emailed at this address."

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