1,507 reputation
11113
bio website
location Orbiting the Sun (More precisely: probably Prague)
age
visits member for 5 years, 7 months
seen Nov 20 at 10:21

Rents brain for food.

Programmer by day, OpenStreetMap enthusiast by night, bicyclist in-between.


Nov
18
awarded  Caucus
Apr
30
awarded  Yearling
Mar
27
comment Determine if file is in the process of being written upon?
How exactly is the file being transferred? For example, rsync uses a temporary filename during the transfer (by default), and only after the file is completely transferred, renames it to the actual filename.
Apr
30
awarded  Yearling
Apr
11
comment it is good and safe to use debian software raid?
This depends also on the RAID level used - as a rule of thumb: RAID1 is reliable but storage-hungry, RAID5 is problematic, RAID6 has both advantages and drawbacks. Don't even think about RAID0. RAID10 is an option, but not something I'd recommend for a beginner (pardon my assumption). See also: en.wikipedia.org/wiki/RAID#Standard_levels
Dec
20
awarded  Popular Question
Oct
23
comment Weird PHP upload behaviour
Do you have any non-ASCII characters in the filenames? This has sometimes triggered seriously weird behavior, both client- and serverside.
Aug
9
comment How to point sub-domains to different local IP
@thang nhoc: Please edit your question, and add more detail (it seems you have only added more text). Specifically, start by answering the questions above, and include the relevant part of the configs.
Jul
26
comment Why couldn't MAC addresses be used instead of IPv4|6 for networking?
@tylerl: Yes. So what? Are you saying "hardware vendors are known to be infallible, therefore this cannot happen"? It has happened, multiple times, in the wild. We could be rightfully upset about this, it should never happen, but it does happen. We need to cope with an imperfect world, not throw our hands up in frustration and say "this should have never happened, and it's not my fault anyway."
Jul
24
comment Why couldn't MAC addresses be used instead of IPv4|6 for networking?
Pedantic correction: reasonably unique; cards with identical HW MAC addresses have been sighted in the wild - this is a "fun" network issue to debug.
Apr
30
awarded  Yearling
Mar
11
comment Is anyone using GPS for time sync?
Nope. The delays introduced with such equipment would give a lower precision than just using any ol' NTP server out there on the Net; the price tag of a purpose-built GPS receiver is not just for the pretty logo.
Mar
11
comment Is anyone using GPS for time sync?
Note that GPS isn't "secure" either: there are constellation simulators out there, which would allow manipulation of the signal as desired.
Feb
25
comment Do Dual CPUs Provide Fault Tolerance?
Hmmm, but even in the case of hard reboot: IIRC if CPU#0 fails, you're still screwed - no POST, which means no further boot, as only the first CPU is used for the early startup process.
Feb
25
comment Do Dual CPUs Provide Fault Tolerance?
@TomTom: Of course, then we're talking things like the venerable TANDEM (and its modern-day successors), not a vanilla x86-64 architecture.
Feb
22
comment RAID for load balancer needed?
It's Murphy: as long as you have a well-maintained RAID 1, nothing ever happens. Try having a server without any disk redundancy, and it will crash and burn at the worst possible moment. (Been there, done that ;))
Feb
21
comment How to define a “challenging RF environment”?
Weeeeelll, throw some old microwave ovens, several cordless landline phones, a few baby monitors, and that tiny RC copter into the mix, and you'll have pretty challenging RF environment, all right (most of such equipment uses the 2.4 GHz part of the EM spectrum). It's hard to find a non-challenging RF environment in any city, nowadays ;)
Jan
25
comment One terabyte of video served per hour - network limits?
@webjunkie: Aha, thanks for the clarification.
Jan
25
comment One terabyte of video served per hour - network limits?
Just to check we're on the same page: several 1Gbit lines that you intend to keep fully loaded at all times are not expensive, then? (and does your provider have sufficient peerings so that your 1Gbit of traffic is not routed through East Elbonia and back, en route to your users?)
Jan
16
comment Fastest way to copy folder that contains many files via SSH
@tomlogic: Good point - in other words, don't use -zfor LAN copy or copying within one machine; test with and without -z for copy across the Internet (one or the other may be faster, depending on many things).