This summer, I finally tired of fighting a constant maintenance, recover, and backup battle with seven different PC's in the family (my notebook, a print server, a LINUX test box, plus wife and kid's machines). It's worse than keeping a small corporate network up and running (where there is no gaming or downloaded "free" software). And we have some real $ tied up in the wifes audio books and the IPOD downloads. So I overhauled our network and backup process.
For backup, I installed a SNAP 2200 800 MB network attached storage device ($1,600, yes expensive but my time is worth it) configured as RAID 1. I'm partitioning each PC into operating system and data drives, then ghosting the operating partition. The data on each machine is backed up incrimentally and automatically to the SNAP server with the SNAP supplied software.
System works OK, Snap appliance is a little noisy (fans) but I put it in a large fireproof box in the crawl space so I don't hear it. File transfer rates are nothing to write home about. But I've got the peace of mind that the data is much more secure against theft, hard drive crashes, most house fires, etc. AND it's not just one more PC to administer, as it is a self contained appliance running a stripped down LINUX kernal. The capacity should hold us for a few years, then I'll probably expand with an additional NAS appliance.
AC power distribution in a large data center can be quite complex. Although local authorities recognize the need for reliable backup power, amazingly, protection of life and property is considered more important than protection of data, and the design of the data center AC power systems reflects that philosophy.
I worked in two different data centers in the 1980-1990 time-frame. They both used Halon fire suppression systems and a sophisticated alarm monitoring system. A halon recharge cost over $25,000. If there was an alarm/fire in the data center, ALL AC power (raw and UPS) was killed and the halon dumped.
Raw and UPS AC power was routed through circuit breaker panels and large AC contactors. Large UPS systems must be designed to be more reliable than the municipal power, not a trivial task. In our centers, multiple redundant (50KW?) UPS systems ran in parallel and the output power was phase synchronized. Battery plants lived in their own vaults. At least one UPS (if not more) could drop off-line for repairs/maintenance without losing power to any equipment. There were numerous sub-panels behind the UPS system that fed individual circuits in different parts of the data center.
When a fire alarm sounded, things got interesting. The staff of 30 had about 1 minute to evacuate the data center. The last one out stood by any door and held a large, red, spring loaded hold-off button depressed. As long as the button was depressed, nothing further happened. We were instructed to hold the button and observe conditions in the data center till either of two events happened. A) We observed serious smoke/fire, in which case we let go of the button and left, allowing all power to be cut, and the halon dump to proceed. Or B) Responding firemen arrived, at which time the system was manually deactivated and the source of the alarm determined and the cause rectified.
Once, an electrician was working on the lighting system and accidently shorted one of the smoke detector sensor alarm loops. This (by design?) tripped the halon dump and killed AC power immediately, with no opportunity to exit first. We staff had to exit in the dark, stumbling into racks of equipment and over tables and chairs through streams of downpouring halon (very noisy, like dozens of scuba tanks being emptied simultaneously). The "wind" of halon emptied dozens of 4' tall boxes of wide format printer paper feeding the dozen or so chain printers. Tens of thousands of feet of paper were blown randomly all over the center.
I work today around much smaller data center, but the convention is still to use a small number of large UPS's, not a large number of individual UPS's to drive individual PC's. I'm told there are some code limitations, but mostly it boils down to cost and reliability. The batteries in small "home/office" UPS's wear out pretty regularly and somewhat unpredictabley. Most are "switchers" that do not decouple power spikes and noise on the mains completely. It is best to have a well designed backup power system consisting of redundant UPS systems in parallel, and an autostart emergency generator (which is often required by code in large buildings anyway).
Run a 1" smoothwall flexible duct from as many sides of as many rooms as you can stand to a central communications closet. Some types come with pull string already blown into the duct.
At each room end, terminate the duct in a deep 4-square box mounted flush with the drywall. Run duct into the basement, crawl space, attics, roof, and to the phone/cable entrance on the rear of the house.
In my house, I ran from the wall through the sill into the crawl space on the first floor. I ran from the wall into the attic on the second floor. I had the electrician install a single 3" EMT conduit between the crawl space and the attic. My "telecommunications closet" is in the crawl space, and if I had it to do over again, I would sacrifice space on the first floor for something I could access and work in more easily.
Do a little study on installation practices and code requirements. Keep bends to a minimum. Lots of information on the net.
Now you can pull whatever kind of wire/coax/fiber into any wall you want for the life of the house. In 20 years, you may want some type of cable in the wall that hasn't even been invented yet!
I bought a used Mazda once that had a hidden magnetic switch wired in series with the fuel pump power lead. If the magnet wasn't in place on the underside of the dash, the car would not start.
I really never used it, but it is the same principal as removing parts from the engine.
I was faced with a similar situation when my fourth and fifth grade children wanted to know what computer programming was all about. I found an adaptatoin of the original PC BASIC language (Liberty Basic) that runs in the windowns GUI environment.
It is easy to learn and implements a wide variety of programming constructs (I/O, conditional statements, looping, math, graphics, etc.). I loaded it on the family PC for the kids to play with. My son eventually wrote some of his own programs to generate solutions to the "The Traveling Salesman" problem for a grade school science project.
See LibertyBasic
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This summer, I finally tired of fighting a constant maintenance, recover, and backup battle with seven different PC's in the family (my notebook, a print server, a LINUX test box, plus wife and kid's machines). It's worse than keeping a small corporate network up and running (where there is no gaming or downloaded "free" software). And we have some real $ tied up in the wifes audio books and the IPOD downloads. So I overhauled our network and backup process.
For backup, I installed a SNAP 2200 800 MB network attached storage device ($1,600, yes expensive but my time is worth it) configured as RAID 1. I'm partitioning each PC into operating system and data drives, then ghosting the operating partition. The data on each machine is backed up incrimentally and automatically to the SNAP server with the SNAP supplied software.
System works OK, Snap appliance is a little noisy (fans) but I put it in a large fireproof box in the crawl space so I don't hear it. File transfer rates are nothing to write home about. But I've got the peace of mind that the data is much more secure against theft, hard drive crashes, most house fires, etc. AND it's not just one more PC to administer, as it is a self contained appliance running a stripped down LINUX kernal. The capacity should hold us for a few years, then I'll probably expand with an additional NAS appliance.
AC power distribution in a large data center can be quite complex. Although local authorities recognize the need for reliable backup power, amazingly, protection of life and property is considered more important than protection of data, and the design of the data center AC power systems reflects that philosophy.
I worked in two different data centers in the 1980-1990 time-frame. They both used Halon fire suppression systems and a sophisticated alarm monitoring system. A halon recharge cost over $25,000. If there was an alarm/fire in the data center, ALL AC power (raw and UPS) was killed and the halon dumped.
Raw and UPS AC power was routed through circuit breaker panels and large AC contactors. Large UPS systems must be designed to be more reliable than the municipal power, not a trivial task. In our centers, multiple redundant (50KW?) UPS systems ran in parallel and the output power was phase synchronized. Battery plants lived in their own vaults. At least one UPS (if not more) could drop off-line for repairs/maintenance without losing power to any equipment. There were numerous sub-panels behind the UPS system that fed individual circuits in different parts of the data center.
When a fire alarm sounded, things got interesting. The staff of 30 had about 1 minute to evacuate the data center. The last one out stood by any door and held a large, red, spring loaded hold-off button depressed. As long as the button was depressed, nothing further happened. We were instructed to hold the button and observe conditions in the data center till either of two events happened. A) We observed serious smoke/fire, in which case we let go of the button and left, allowing all power to be cut, and the halon dump to proceed. Or B) Responding firemen arrived, at which time the system was manually deactivated and the source of the alarm determined and the cause rectified.
Once, an electrician was working on the lighting system and accidently shorted one of the smoke detector sensor alarm loops. This (by design?) tripped the halon dump and killed AC power immediately, with no opportunity to exit first. We staff had to exit in the dark, stumbling into racks of equipment and over tables and chairs through streams of downpouring halon (very noisy, like dozens of scuba tanks being emptied simultaneously). The "wind" of halon emptied dozens of 4' tall boxes of wide format printer paper feeding the dozen or so chain printers. Tens of thousands of feet of paper were blown randomly all over the center.
I work today around much smaller data center, but the convention is still to use a small number of large UPS's, not a large number of individual UPS's to drive individual PC's. I'm told there are some code limitations, but mostly it boils down to cost and reliability. The batteries in small "home/office" UPS's wear out pretty regularly and somewhat unpredictabley. Most are "switchers" that do not decouple power spikes and noise on the mains completely. It is best to have a well designed backup power system consisting of redundant UPS systems in parallel, and an autostart emergency generator (which is often required by code in large buildings anyway).
Run a 1" smoothwall flexible duct from as many sides of as many rooms as you can stand to a central communications closet. Some types come with pull string already blown into the duct.
At each room end, terminate the duct in a deep 4-square box mounted flush with the drywall. Run duct into the basement, crawl space, attics, roof, and to the phone/cable entrance on the rear of the house.
In my house, I ran from the wall through the sill into the crawl space on the first floor. I ran from the wall into the attic on the second floor. I had the electrician install a single 3" EMT conduit between the crawl space and the attic. My "telecommunications closet" is in the crawl space, and if I had it to do over again, I would sacrifice space on the first floor for something I could access and work in more easily.
Do a little study on installation practices and code requirements. Keep bends to a minimum. Lots of information on the net.
Now you can pull whatever kind of wire/coax/fiber into any wall you want for the life of the house. In 20 years, you may want some type of cable in the wall that hasn't even been invented yet!
I bought a used Mazda once that had a hidden magnetic switch wired in series with the fuel pump power lead. If the magnet wasn't in place on the underside of the dash, the car would not start. I really never used it, but it is the same principal as removing parts from the engine.
I was faced with a similar situation when my fourth and fifth grade children wanted to know what computer programming was all about. I found an adaptatoin of the original PC BASIC language (Liberty Basic) that runs in the windowns GUI environment. It is easy to learn and implements a wide variety of programming constructs (I/O, conditional statements, looping, math, graphics, etc.). I loaded it on the family PC for the kids to play with. My son eventually wrote some of his own programs to generate solutions to the "The Traveling Salesman" problem for a grade school science project. See LibertyBasic