Wikipedia:Reference desk/Archives/Computing/2017 August 14

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August 14[edit]

Domain Provider versus Host versus DNS[edit]

I'm trying to understand the following sentence:

"GoDaddy is the website's domain provider, directing internet users and search engines to its URL. GoDaddy doesn't, however, host The Daily Stormer's content."[1]

What exactly is GoDaddy's relationship with this website? The article says GoDadday is directing internet users and search engines to its URL. Isn't that what a Domain Name Server does? A Quest For Knowledge (talk) 14:34, 14 August 2017 (UTC)[reply]

The site has apparently been hacked (and there's various places in the chain of responsibility, to which your question pertains, where that might have happened) so I can't answer for how it is normally configured. But some domain providers also provide (often for free) a simple redirect service whereby they host a redirect, which always returns a HTTP 301 to some other website. So that's a tiny middle ground between simply being the domain name provider and actually hosting the whole website content. With this website hacked (and in practice, with its hosting arrangements being in a state of flux) it'll be hard to say if that's what GoDaddy is doing in this specific case. -- Finlay McWalter··–·Talk 15:02, 14 August 2017 (UTC)[reply]
I think that means that they are both directing Internet users and search engines to the IP address, and are providing the CPU and disk service for the web site, but the disclaimer means that they are not responsible for the content. I think it's similar to the disclaimer that a rental car company can provide. They are only providing the car, and are not responsible if you use the car as the getaway for a bank robbery, or use the car to transport fentanyl. They are hosting the web site, but are not responsible for its content (which may be fascist nonsense). Robert McClenon (talk) 15:06, 14 August 2017 (UTC)[reply]
The sentence "GoDaddy is the website's domain provider, directing internet users and search engines to its URL. GoDaddy doesn't, however, host The Daily Stormer's content. " is simply wrong. GoDaddy is the Domain name registrar for the site. As such it provides the association between the domain and a DNS server that knows how to resolve addresses in that domain. GoDaddy is almost certainly also acting as this authoritative DNS server for the domain - these services are nearly always (but not necessarily) bundled. But neither "direct anything to an URL" - what these services do is to associate an IP address with the hostname part of the URL. --Stephan Schulz (talk) 15:10, 14 August 2017 (UTC)[reply]
I will note that, although GoDaddy was not responsible for the web site's content, they appear to have concluded that its content violated their Terms of Service (TOS) and have cancelled the hosting contract. Robert McClenon (talk) 15:53, 14 August 2017 (UTC)[reply]
OK, so GoDaddy is the registrar. That makes more sense. A Quest For Knowledge (talk) 20:12, 14 August 2017 (UTC)[reply]
As a customer, always make sure, You to own the domain and order the provider to host it as a service, only. --Hans Haase (有问题吗) 21:58, 18 August 2017 (UTC)[reply]

PSU voltages[edit]

I'm not sure if this is a science desk or a computer desk question so feel free to move it if you like. I have a computer power supply unit that outputs "+3.3V, +5V, -5V, +12V and -12V." I don't understand how minus voltages work at all but if I connect the +12V to something and use the -5V as negative terminal would the thing I connected it to get +7V? — Preceding unsigned comment added by 196.44.242.20 (talk) 15:05, 14 August 2017 (UTC)[reply]

No. You'd get +17V. As our Power supply unit (computer) says, the -5V rail has been largely abandoned for a very long time and even before then was barely used and so is unlikely to support much power so this wouldn't work well. And considering that and other factors, I doubt the PSU even if it did have a -5V would be happy with this setup. (Also the -5V was only provided on the AT/ATX line so under normal circumstances, you'd either need to be doing this on the motherboard, or use some sort of adapter and you probably risk killing the motherboard if you were careless. If you want 7V you need to connect to the +12V and +5V (or -12V and -5V). Some people did actually do this with fans since you can easily get +12V and +5V from the classical molex connectors, but it's not considered good practice and does carry some risks [2] [3] [4] [5]. Still it often worked and the number of issues causes seemed quite low compared to the number of people doing it, but of course the +12V and +5V lines are a lot more important so are likely to be a lot better regulated than the -5V. Nil Einne (talk) 17:56, 14 August 2017 (UTC)[reply]
The -12 line is usually of low current capability, as it was really only used for the RS-232 serial port where it was called on to deliver very little current. I still have several ATX power supplies as spares for my 1998 Compac computer running PCDOS 7.0 and they're all rated at 0.5 Amp on the -12V lines. Akld guy (talk) 21:39, 14 August 2017 (UTC)[reply]
Half an amp is still quite a lot, in electronics terms.
A problem with using PC PSUs is that they expect to see the load of a typical motherboard and disk(s), and taking a very low current instead may leave them in a shutdown mode. This is pretty commonplace for switchmodes.
I would be wary of cross-connnecting the outputs like this. If you do, assume only the current capacity of the smallest, at most. Andy Dingley (talk) 21:48, 14 August 2017 (UTC)[reply]
See the article Power supply unit (computer), there's a simplified circuit diagram and some documentation, the voltage rails were and are used for. Before the MAX-232 signal converters came, the 1489 and 1488 converters do not generate the output voltage levels and the -12 volts were required. --Hans Haase (有问题吗) 22:04, 18 August 2017 (UTC)[reply]