Archive for the 'Services' Category

Strange Mac OS X name resolution

Thursday, December 24th, 2009

Now on one Mac I have a strange issue I never had before: Sporadically, e.g. after a fresh boot, name resolution does not work. While nearly every kind of application is effected, Safari, Mail, etc. even ping. To my surprise, though, dig(1) does reliable work in this kind of stuck system state. After some review it turned out that Mac OS X provides different DNS resolution services of the classic Unix / Posix services - that apparently can get out-of-sync from what the classic resolution configuration would use. To flush them:

10.4: lookupd -flushcache
10.5: dscacheutil -flushchache
10.6: sudo killall -HUP mDNSResponder

For me, under Snow Leopard (Mac OS 10.6), killing the mDNSResponder did actually indeed help! I’ll have to keep an eye on the situation, if it’s getting too annoying I’ll have to try a clean re-install. Sigh!

The reliability of T-Mobile Germany

Saturday, May 16th, 2009

As child I already learned that the German Telekom is not the most friendly and providing company in the world and due to the past experienced I avoided it like the plague for many years. Recently, however, with an US iPhone used in conjunction O2 in Germany I desperately waited long for an unlock possibility to arrive, and eventually decided some 6 months (or so) ago that it’s time for the 3G/UMTS update and had to take the bitter pill T-Mobile Germany is.

I have to say I really regret it. So much that this Saturday morning is a good time to write about it. Not only is it the most annoying customer care company calling ever 1-2 month asking me what other stuff they can sell to me, no: not even their basic network functionality works solidly. Never before was I more often off-line than on-line. Very often non-German server are simply not reachable. Most notably my daily email check in the morning does just lead to “The connection to the server … failed.” and international sites like engadget.com are not reachable. Strangely this morning other Germany sites like heise.de did work, just not our comanpies website and mail server. And this is after a total cellular network
meltdown
that made headlines even in all regular German newspapers when their network went off-line, national-wide, … And this morning I called to complain about my ongoing “network routing issues” and the person told me (after the automated voice system failed to understand my request) that:

.. they have a known network issue right now and are working on it, … Voice calls should work, but I’m lucky that some German internet sites work for me at all. …

Now this was a 7 AM when I got up and now at 10:30 PM it is still not fixed, …

I even went on asking him if, deduced form my ongoing intermitted problems, they have weekly network problems. But the guy did not wanted to comment. I take this as yes.

I’ll now try to get rid of this iPhone contract early, because, frankly, my first US (UMTS-less, G1) iPhone my girlfriend keeps using with an O2 SIM and network always works without a glitch.

The worst part is that I often get a near heart-attack in the morning because the first thing I get to see is a “failed connection to our companies e-mail server”, that always kicks in some “oh my god are some our servers down” emergency mode in my brain.

I really wonder how Germany’s largest phone and internet provider can have so many ongoing basic “routing” or similar problems. I mean routing some data packets from cellular towers properly should not be too much of a deal with a network also connecting some million of landlines for analog, digital ISDN and DSL. Or are those landlines messed up right now, likewise? Thanks god I cannot tell as my landlines are covered by other providers that apparently do care more about their customers.