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Comment 2TB is the limit in the accountancy system.... (Score 1) 204

That's as much as the carrier's engineers say you could theoretically get through without a limit if you ran it 24x7, but you're really not going to get that in the real world.

They do traffic management to prioritise certain traffic, up what they can see as VoIP (Which is hilarious as Facebook, Google Hangouts, Skype etc calls suck but SIP connections are flawless), HTTP (80) / HTTPS (443) are again, up. Try to torrent something? 64kb during peak hour, close to useless in my experience, but out of hours it picks up to a couple of hundred KB / sec.

Also, in the real world, once you go over 20GB you get a phone call. A friend of mine was using a SIM of theirs for a backup connection in his house, and he got a phone call from them saying something along the lines of "Is everything OK with your equipment, you seem to have gone from using not much to using a lot in a day or two" he told them it was the backup to his cable and they went "OK, thanks" and left him be.

So, they don't seem unreasonable about large usage as long as it's not every month. For â20 / month, I thought it was quite decent value actually.

Ordinarily I'd use 2 - 3GB, but if I hit 5 or 6 because I was tethering I wouldn't even think about it, and in my experience, neither did they.

Comment Re:the above is wrong (Score 1) 72

Sorry, what?

Even the kernel isn't accurate at doing this. On heavily loaded systems I've seen 20ms wait before a packet is stamped before. Pre-emptive kernels and everything else means that a packet might be sitting on the network card or in a buffer without it being collected and stamped by the system. The only way to have accurate timestamps is to have something like a Napatech or Myricom card using a third party time source.

Comment Re:Interesting (Score 1) 72

I'm guessing your using standard ping there, well, the problem is that the packet being generated and the time sent and received times are coming from timers most likely in the app itself, it's doing the calculation, so if you ask the system for time 1 and it goes "00:00:00:00" and you ask for the time again and it says "00:00:00:01" it'll get reported at 1ms, but the packet may have entered the system a lot faster than that, it's only because you're using a 1ms accuracy time stamp that you're getting 1ms. Also, if you ask for a timestamp and the system takes a long time to respond to that request, you're timestamps are going to be out again.

Accurately measuring all this stuff, there's whole sections of the networking industry built around it.

Comment Re:Greece cannot make debt payments... (Score 1) 743

People are still starting businesses here and people that are dodging tax through Ireland are employing thousands upon thousands of people. (Tech: Microsoft, Oracle, Google, Facebook, Twitter. Pharma: Astrazeneca, Phizer, ICON Finance: Creddit Suisse, BoAML, JP Morgan, SIG) Those tax breaks on income tax happen all the time in other countries, a lot of different countries give out large tax breaks for large employers, they know they'll get the money back in income tax from employees.

Double Irish might go away, but the lower tax rate won't any time soon. The Irish government know which side of their bread is buttered.

Comment Re:Summary of above post (Score 1) 287

> get a cheap GPS unit and attach it to a local server.

Yes, I should buy 40,000 cheap GPS units. Actually, you know what? I'm going to ask Dell, HP and Intel to implement this. Oh crap, I can't, 'cause I can't get a GPS signal in a DC.

You really didn't think about this too hard did you? People have been working at this for years, NTP does a heck of a lot of stuff to ensure that the clock is accurate, and how much you can trust the information you're given. NTP isn't a cheap hack, it's mathematically brilliant for distributed systems.

Comment Re:I have two problems with this article. (Score 1) 287

Stuff dependant upon time of day, ACL restrictions, replay attacks of time based credentials (Tokens I guess in the previous post).

Even log analysis across systems if the clocks in different systems are drifting faster and slower according the the temp of the system would be a major PITA.

Let's not start looking at the consequences to financial exchanges (Expiring bond markets, matching trades across disparate systems), telephony (TDMA, billing systems), depending on how far you take it, train signalling, air traffic control... Basically, this list is endless.

Comment Re:How about we hackers? (Score 4, Informative) 863

> From what I can see on the RHEL lists that have many professional admins, there's been no hue and cry, no sky falling, etc.


I don't know about you, but I admin about 400 odd servers, we've got about 40,000 globally. I've still got RHEL 4 boxes (Soon to be decomm'ed) Only some (5 - 10) of the boxes I built last year are RHEL 6. Everything else is RHEL 5 still. It works, I've no need to go above that for our purposes.

Now, I've got some new re-purposed boxes that I've started building with RHEL 7, and I've just started dropping myself into systemd.

Changing the startup scripts of *every* vendors application out there? No commercial applications are setup for systemd, this is going to be a loooooooooooooooong drawn out process to make this work.

RHEL 7 is brand new, very few people have started using it, the customers haven't had a chance to comment on it yet.

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