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Comment Re:the above is wrong (Score 1) 71

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) 71

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.

Submission + - After Snowden: Prioritising Free Software for Computing You Can Trust (

An anonymous reader writes: The president and the executive director of April, the French free software advocacy association, published this week an article in the popular French newspaper Libération entitled "After Snowden: Prioritising Free Software for Computing You Can Trust"

Here are two excerpts :

"The mechanism that establishes computing you can trust is not any different from that which regulates a modern democratic society. It essentially rests on the right to vote, associated with access to objective information. Free/libre software, which, in a global computer base dominated by Microsoft, is gathering momentum, is the only one to follow these principles: its code is accessible to everyone and its modifications are collectively decided on by a community of developers. The installation of a backdoor by the NSA within the source code of a free program is theoretically not impossible, but it will always remain much less likely than it would be within a proprietary program, whose code is kept secret."

"That said, technical solutions have their limits. What we need is political awareness, both at the governmental level and at the individual level. This choice is going to require some efforts from each of us: proprietary software programs have for years aimed to infantilize our relationship with IT, on the assumption that the less we knew, the more we would behave like captive customers. Regaining control of one's computing is not easy, but it is an essential civic initiative. Everyone should try to give priority to free software."

"I have five dollars for each of you." -- Bernhard Goetz