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Comment Re:Hardware requirements (Score 2) 641

That's why (if they're smart) there are three spare ISA cards on the shelf, or more, preferably already installed in identical machines.

I work with a group that has ISA-based cards for research data acquisition (EEG variant, if I remember correctly) with a study that's been running for 20+ years on the same subjects. They can't swap the hardware, because the output data wouldn't be directly comparable -- newer equipment is "better", but in terms of continuity for the research, they need the same, not better. There's a stack of old 286 or 386 machines in the basement, and we run a Netware server (since they were originally tested with the DOS Netware clients over IPX, we continue to use it) to get the data from those DOS boxes to something vaguely modern over NFS.

ISA also had the oddity that the clock speed for the bus wasn't fixed. It's variable based on CPU speed on the original systems, the last machines shipping with ISA would lock it at 8Mhz or so (i.e., a 1/4 multiplier on a 33Mhz bus CPU, like a 486DX2/66).

They've considered it. And they're probably terrified of that happening -- it's either going to mean the end of a research project, or a multi-million dollar expense along with a major disruption in work. If it was less dire than that, they probably would have already replaced it.

Comment Re:Reflections (Score 1) 960

Way late to answer, but you'll probably be notified.

Typical consumer drives are intended for relatively low-heat, low-vibration environments. The firmware on the drives is typically optimized for desktop access patterns, and will automatically slow or stop the motor to save power. The drive assembly itself is quite a bit different -- lower quality bearings, less isolation on the heads (protection from vibration). Datacenters are hot, noisy, and vibrate badly. Consumer drives fail in that environment at a lot higher rate.

Firmware is typically optimized very differently, for different access patterns, power usage, etc.

The same model consumer drive, over different revisions, may have different capacities. In a RAID-1 config, if the replacement drive, or the drive you buy to create the mirror, is a few hundred sectors smaller, there's no joy and no mirror. If I remember correctly, some consumer-targeted RAID controllers actually reserve a bit of the disk and don't present it to try to protect against that particular problem. I ran in to that a lot in the past, not as much recently, but it still happens. Hell, back in the mid-90s I had that happen with enterprise SCSI drives that weren't vetted through a vendor that pushed it -- same model of the Barracuda from a random cheap-ass vendor (Dirt Cheap Drives, if I remember correctly), different capacities. Ruined my bloody weekend.

Going outside the facts, and moving to the artificial reality of vendor contracts, HP or Oracle may well respond that they won't support something until you pull the consumer-grade shit out of the machine.

Now, after all of that -- I do use consumer drives in servers when it's worth it, and when I can afford the risk. My backup media servers (Netbackup) are Sun x4500s with 48 internal disks -- those disks have been swapped with cheap-ass WD 2TBs and have close to 100TB of available space. The disk is managed by ZFS with single-parity RAIDZ and is used for staging backups before pushing to tape to move offsite (weekly/monthly), and duplicated storage of short-term backups (daily).

I'll use it for scratch space, and I'll use it when I can afford to lose it (or at least lose access until I rebuild and restore). If there's data I care about on there, it's typically using ZFS so that block-level checksums are done and I'll at least know that the data is bad without silent corruption.

I've got shit to work with for budget (public higher education), and the cheapest reasonable "enterprise-like" disk I can get runs us about $400/TB usable -- Dell MD3200 SAS-connected array with dual controllers (four hosts redundant, 8 non-redundant, and it's really an OEM LSI Engenio (sp)). Best I can do for disk on the SAN is more like $600 (Nexsan, Dell/LSI MD32xx), and those prices aren't for a single TB purchase. Most SAN-connected disk is still in the $1000/TB range and higher. I'm counting these prices including support (NBD response, usually) for three years or so. The other constraint is that I want the vendor to exist in a few years and have some track record, and I need to be able to get it past purchasing, which usually means state-or-U-level contract -- I've had to support some random shit bought from HPC vendors, usually OEM'd Infortrend or similar, and don't want to deal with that shit ever again.

It's all about the application and level of risk that's acceptable for that app/system. I'll never stick shit disk on a SAN to use with a VMware cluster, but I will happily throw a pair of cheap disks in a standalone ESX server that's running developer VMs or testing. Prod systems need to be expensive shit, sadly, to avoid giving the vendor an excuse (I'm looking at you, Oracle).

The speed increase matters once in a great while too -- more RAM is usually more effective, and cheaper.

Comment Re:Hash Collisions (Score 1) 386

Which might make for some interesting theoretical attacks -- if I can craft a block with the same hash as a block I'm interested in, I can read the contents of the other block.

// Assume that an information-leak bug that allows the attacker to read the hash values and other metadata necessary, which is entirely possible.

Comment Re:Palm has retired the OS (Score 1) 290

Then your company would likely frown on you working around that by indirectly syncing the personal machine as well. The technical measures in place that prevent you from connecting your laptop to Exchange are merely a way of enforcing policy. You're still violating the policy even if it doesn't stop you.

I don't give a shit, but I bet your company would.

Comment Re:Stay classy (Score 1) 290

I mostly agree with you, but ADB made it all the way from the Apple IIgs [1986] and IIc+ (6502/65816 CPU with Apple II OS), Mac SE (68000, System 5 or later), up through the beige PowerMac G3 [1998]. That's about a 12 year run. Even beyond that, it apparently was still used for internal keyboards on laptops until the Intel switch.

Comment Re:A REALLY bad place to ask for appreciation (Score 1) 232

If you think we *want* to be stuck on IE 6, we don't. We don't really care. However, the developers wrote some asinine ActiveX shit that doesn't work on IE 7 or IE 8, and sure as fuck don't work on Firefox. Or, we're using PeopleSoft software that isn't certified on anything about IE 6, etc.

For XP? Well, by the time Vista was working well enough with the internal apps to roll out, Windows 7 was in beta. Why the hell would I go through upgrading everything to Vista just to have the same people turn around and want Windows 7 next week, but we can't afford to have any departments down for a day to reimage.

It comes down to the golden rule of the sysadmin -- if it's working, don't fuck with it.

Comment Re:hey guys, no more sysadmin bashing ... (Score 1) 232

I've dealt with enough developers that I'd say about 1/2 to 2/3 were competent, and some of those, while competent developers, didn't have anywhere near enough knowledge to be allowed to administer their own machine.

Of course, I'd probably say the same about 1/2 of the sysadmins I've worked with as well, and very few sysadmins have the knowledge to be competent developers. The higher percentage of incompetent sysadmins stems from not understanding security, or not understanding how to balance security with usability.

Note my use of the word knowledge -- most developers could be competent sysadmins, but don't have the knowledge base. If you're developing database-driven web applications using .NET, how likely are you to need to know details of filesystem ACLs, or how a rootkit may insert itself in to a OS kernel? How many sysadmins are going to know how to write (or even use) a database stored procedure, and more importantly, /when it's appropriate to do so?/

Unfortunately, most people don't have the wisdom to understand where their own knowledge ends. I understand quite a bit about a lot of topics, but I'm willing to let an expert (doctor, dentist, mechanic, athletic trainer, etc.) do their jobs. Why don't people have the same attitude about sysadmins? (Hint: I think it's because when you fuck up your car, you pay to fix it. If you fuck up your PC there's no direct financial penalty for you personally.)

Comment Re:Maybe we could couple it with Guy Fawkes day (Score 1) 232

It's not "one minute out of work."

You're focused on a large, complex problem. Someone interrupts you, and you have to go deal with them. When you get back to the large, complex problem, you lose a lot of time figuring out where you were and picking up the pieces of the troubleshooting.

That's not even factoring in that your co-worker called the help desk, someone there had a write a ticket, send it to a deskside support person, who had to leave their desk, come down, and do the "one minute" fix. Total time? Probably more like 30 minutes where your co-worker wasn't working.

I agree with one of the other posters -- I would have had *your* ass. Sending an email to the entire company to apologize to the tech? That's a cannon to kill a gnat -- but don't forget that you're the gnat, asshole.

Comment Re:Maybe we could couple it with Guy Fawkes day (Score 1) 232

If you really think the sysadmin is making the decision to block flickr, I (hope and expect) you're wrong. Generally, it's some asshole who's spending his day looking up nudists on flickr, someone else sees the monitor and complains, and because the asshole is the manager's nephew/golf buddy, the problem is that was allowed -- tell the sysadmins to block it.

Even without that contrived scenario, if they're using a third-party service for the filter, like websense, you block a category -- porn, blogs, social networking, sports, gambling, etc. Because flickr has plenty of NSFW images, filters may include it in the porn category, as well as social networking (comments, friends, etc.)

If the filter is blocking it by default, in a non-work-related category (porn), how will you justify *un*blocking it?


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