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How Do I Provide a Workstation To Last 15 Years?
An anonymous reader writes "My father is a veterinarian with a small private practice. He runs all his patient/client/financial administration on two simple workstations, linked with a network cable. The administration application is a simple DOS application backed by a database. Now the current systems, a Pentium 66mhz and a 486, both with 8MB of RAM and 500MB of hard drive space, are getting a bit long in the tooth. The 500MB harddrives are filling up, the installed software (Windows 95) is getting a bit flakey at times. My father has asked me to think about replacing the current setup. I do know a lot about computers, but my father would really like the new setup to last 10-15 years, just like the current one has. I just dont know where to begin thinking about that kind of systems lifetime. Do I buy, or build myself? How many spare parts should I keep in reserve? What will fail first, and how many years down the line will that happen?"
Or just get quality components to begin with.
At the office, I'm still running a 350mghz PowerMac G4 computer (the bugger is 10 years old) as a server.
All original components. None failed. System still has it's original bleeding-edge 320megs of Ram, runs Mac OS X Tiger.
It was given a new 40gig baracuda drive that's been sitting on shelves for years. had never been used.
We use this machine as a slowest-denominator software test platform for a product in development and as a distributed networked compiler farm node and backup server for another more important machine (it backs up the backup machine's main OS, not it's files).
MS can argue all it wants about Apple making "aesthetic" machines, they actually use good components. Current XServe hardware being another case in point.
Not so with the flash drives. I was looking into an equivalent for MTBF for flash drives, and not finding one i started looking into the maximum capacity of writes, and found an article extolling a sort of half-life figure for flash drives. looking into the drive i have installed in my media center (for Quiet) an OCZ model. i found that i'd have to be writing to the drive at maximum capacity 24/7 for 18 years before the available capacity of the drive would decrease by half. they're quite long-lived, if the maximum writes per sector figures are to be believed.
Keep in mind that it may be prudent to pick less-reliable hardware that should still last 4 or 5 years (most likely), over slightly more-reliable hardware, WHEN the price difference makes it more cost-effective to ANTICIPATE replacement.
Even the most reliable components may be expected to fail in 5 years.
I think he's been very fortunate that his setup has lasted 15 years. On average, a computer has had a lifetime of 5 years, before some hardware failures occur. To be honest.. in many cases, newer hard drives has been less reliable or has not lasted as long.
The higher data density results in more failures not less. The more bits (at essentially the same rate of defects), means it's much more probable for there to be at least one sector defective on a larger drive.
Power supplies can fail within 1 year or 10. It's random, so there can be no guarantee that the setup will last 15 years without any hardware replacement. (Even using the hardware he has right now, something could have failed in 1 year. A drive could go completely bad tomorrow.)
So get a very decent power supply, preferably one that is efficient at the anticipated load (which you should calculate for the chosen hardware), but can handle a lot more.
Using SSDs would improve reliability if used in a RAID 1 array, and a choice made with decent cache and wear-levelling, provided your app is reasonable they should last 50 years (typical use level), more likely the RAM dies first.
But unfortunately, the suitable SSDs of any reasonable size are also highly expensive. the cheaper ones don't have the few gigabytes or so of battery-backed RAM cache that would be necessary for high speed. --- Which come to think of it, may also be a reliability risk, since most types of rechargeable batteries don't last 15 years.
And I expect you don't need high speed for a small veterinary database, so the most inexpensive SLC or MLC may be just what the doctor ordered..
Another possible application for flash is simply to boot off of it, and then use an ordinary mechanical hard drive for storing your data. This way, mechanical wear is not introduced when you boot your OS, and writes are rarely required.
However, Windows XP (or Vista) is not suitable for this, as it likes to write to its own boot media. A Linux-based kiosk with a mysql-backed database app of some sort could work great there.
Make sure you get a lot more space than you need, i.e. try to fit everything you need within 5 or 6 GBs. And use a 50gb drive, so you can have an "active" partition and "backup" partition
Minimize mechanical wear on your drives by getting enough memory to run the workstations without a swapfile or pagefile. i.e. get 1GB or 2GB (a workstation that can use ECC memory is better, as you reduce the small possibility of silent data corruption), and make sure you disable all paging/swapping features within your OS.
Use the most reliable drives available for a reasonable cost; these are probably NOT 1TB 7200RPM drives; these are more likely 30gb 5000RPM drives that come with a 3 year or 5 year warranty.
Have each workstation backup the other workstation, i.e. so there are always two copies of the database. This is in addition to daily backups to external media to be stored offsite.
Unless you are using a UNIX/Linux OS with a journalled filesystem (or something like ZFS), it's pretty much a fact, that you are likely going to need an OS recovery at least once.
Each workstation should have two drives and a 'working partition' and backup partition. That you manually refresh every few months. Even better if they are separate physical disks (but again, more expensive)
Reliability will be maximized if you use a UNIX or Linux based application. And you minimize unnecessary reads and writes to your mechanical media, and minimize unnecessary load (and therefore heat) emitted by your hardware.
In any case, the usernames logging into the worksta
My father is also a veterinarian with a private practice... I don't know enough about the exact details of his software but can give you the high level, as well as issues he has had, etc.
First, he has gone through a few (2 or 3 not sure) completely different systems (hardware and software) in the last ~20 years of having a "computerized" practice.
When they got the first system the practice was much smaller - 3 vets in the partnership and a handful of employees. Over time it has grown to employ another 3 full time vets and a much larger staff. So that's question 1: it may be small now, but do you expect it to grow? 2 networked workstations won't be enough if he may have 20+ employees in the future, and deciding on something today (hardware and software) that at least supports upgrades will go a long way to prevent having to redo the whole thing later.
Question 2 is related to the nature of his practice. Is it a relatively low-tech, rural practice or is he planning on modernizing/keeping up with technology? Back in the 70's the most high-tech equipment in most practices was the x-ray machine. Since then, my dad's practice has added an ultrasound, laparoscope, and most recently a digital x-ray that allows inexpensive, near instant access to results (without having to develop, etc) as well as convenient storage, display on a number of terminals in exam rooms, even convenient consults from remote specialists. That's in addition to all of the other benefits that come with professional veterinary software packages, like integration with outside labs to get faster test results, tracking of inventory and reordering, etc.
Question 3: how much does he care about his data/computer systems? If down is it a minor inconvenience or a crippling liability? If the latter, do you really want to build something for him with off the shelf parts with no support? Are you available for 24/7 support if something goes wrong? My dad's practice has 24/7 1 hour business support (from IBM? or something similar). If a system goes down, HDD dies, network is flaky, etc they will have someone there in less than an hour to replace hardware, diagnose issues, restore backups, etc. Sure, that service costs money but has been necessary several times over the past couple decades and saved their ass when it happened. On the other hand, if your father is basically using the machines for payroll, inventory, and bookkeeping, he might be ok with a simple backup system and your help when something goes wrong...
Anyway, I know my dad's practice now has a central server (I think just standard workstation HW with RAID and nightly backups?), a few terminals (I believe all Windows-based, since that's what the veterinary SW runs on), and most recently a medical grade monitor and high-res video card for x-ray display, along with a couple of WiFi laptops they use in exam rooms to show x-rays, look up histories, data entry, etc. All of it comes with 24/7 HW and SW support, which for their type of usage (and the fact they don't want or need a full time IT employee) I'd consider a must have...
Anyway, hope that helped. But to summarize I'd rank the goals as (not counting cost, which of course needs to be factored in depending on personal situation):
1) minimize downtime/lost revenue
2) allow modernization/support for new technologies as necessary
3) scalable if/when the practice grows in the future
What I would most definitely NOT worry about is the latest fancy hardware. If he's still surviving on a 486 with 8MB RAM, any reasonable modern HW will be cheap and more than enough. By all means go for reliability over performance, especially if you are doing it yourself. If buying HW/SW/support from a professional company, they will make sure the HW is adequate and reliable (since it costs THEM much more in the long run if it isn't).
On the software side, I would consider hosting the DOS app on linux using an emulator such as dosemu or dosbox. The OP's dad would have an environment very similar to what he's using now. I would probably use Debian stable for both boxes, which has very long release cycles and is very stable.
With linux comes the option to replace the DAT tapes with an off-site rsync over ssh. If the main box dies, you'd be able to just swap in the backup box in a couple of minutes. If the data set isn't very large the mirror will complete in a couple of seconds. It's very easy to do:
Create a RSA public/private key pair: ssh-keygen -t rsa, press enter at the password prompts.
Copy the public key to the remote box: ssh-copy-id -i ~/.ssh/id_rsa.pub remotebox.
Have a nightly cron job to push the files: rsync -ave ssh --delete /localfiles/ remotebox:/localfiles.
For bonux points you could even throw in snapshots.
I'm backing up hundreds of partitions this way at work, each with snapshots going back a month. Tapes are slow, unreliable and expensive. I would not use them for any purpose.