Tag: networking

Collapse of the docker0 bridge

We’ve got a printer in the office. I’m not sure how the network is organized, but it’s on a different IP range than the rest of the dev network. And for some reason I couldn’t get it to work.


I solved those problems. I was googling hard, i read dozens of bug tickets and launchpad threads, and though i couldn’t really find anything that exactly matched the problems i had, the intersection of the suggestions always included using pppoeconf, so i gave it a try, ran it, then rebooted and now everything works fine and smooth. I still have no idea what the true nature of the problem was, but it’s fixed so i can’t really care anymore.


So, i got my internet connection back up, but however much i’d love to say “all right”, that wouldn’t be true. I have some problems with it. I’ve to note that i didn’t test every possible combination thoroughly.

The problem is: under Ubuntu, some websites time out. They are not related to each other in any way, not geographically nor based on content. Then, some secure websites load without stylesheets and scripts in Chrome, but load all right in Firefox. Some websites load if i proxy through Tor. Also, Filezilla (and gftp too) is unable to transfer files to/from certain ftp hosts – while some other hosts work all right. Again, no geographic or any such relation between the hosts.

The tricky part is, it all works fine on Windows (at least the problems with Chrome and secure websites and ftp transfers do), so i guess it’s some kind of configuration problem, but i tried all i could find and i couldn’t figure what could be causing it.

On Windows (7) i have the default settings with the username and password for the DSL connection (PPoE). On Ubuntu, i also have the default settings, but i tried changing them, because who knows, it might be some cutting edge tech not yet supported by the servers, but to no effect.

Any and all help would be appreciated.

Super-r net not so super?

Last spring i got the first internet provider i could find: Super-r. As apparent from my plurk and twitter streams, it’s often more of a disconnection than a connection.

I was for example not aware that i had some limitations or rules on my traffic. Apparently there are, because for a day now my internet was cut. After i couldn’t reconnect this morning, i now decided to call the support. Surprisingly they answered at first try, but what they said was more surprising. My net was indeed cut, because i was generating too much traffic.

Oh finally

My computer tricked me. I couldn’t connect to the net since i got back to Japan and i had no idea why. Actually i had plenty of ideas, but none that i could fix. For example my university messaged us of a scheduled downtime last friday, maybe they forgot to switch the router back on? No, my neighbours can still use their net. Is it a cable problem? None that i could see. I even called the provider’s support for some info on what could i do, but they only suggested testing with other computers and stuff. (This was today, since i couldn’t get through to any human on the support line for three days, #hellyeah super-r net.)

Since i couldn’t borrow another pc right away (everyone either used theirs or they weren’t home), i just took the modem and checked if it could get in touch with the tv in the common room (which had a lan port for unknown purposes), and it could. This started to raise my suspicions, but i couldn’t really think of any problem my computer could have except for the failure of the network chip on the motherboard.

On virtual networks

Last time i was playing around with wireless networks, trying to set up a mesh, which is apparently still in a very geeky level of development—meaning it works if you are a linux nerd and can and want to hack your way all down to the kernel, but even then it might be buggy. Now, on Windows that’s obviously not as easy as on linux, as there is no make to change the problem lines. Also, the mesh thing would need to be implemented easily and quickly, possibly natively, which is out of question for now. Or at least if Windows could (simply) set up an ad-hoc network without having to share an internet connection… On the other hand, since we’re moving out of the dorm, and will be spread all over Japan, it’s a natural question how to continue playing together. Using a server would be an option, but that wouldn’t give the other lan options of file sharing, and would probably work with one or two games only. The other option is to set up a virtual network. And i honestly tell everyone, it’s a pain in the ass to find one that knows exactly what i expect of it. That is, to handle networks just like Hamachi does, but without the 16 client limit, for free. Today i took my time and checked out “a few”: Leaf Networks, LAN on Internet, NeoRouter, OpenVPN, Remobo, tinc and Wippien. And naturally i’ve been using Hamachi for over a year now.


Between two tries at the song i’m learning, i decided to write about playing, games, on the computer, with other people. Usually we play by grouping together in a (common) room and then either with cables and a router, or me creating an ad-hoc wireless network for the purpose, or the combination of the two (which, to my surprise, works flawlessly as well). This way the only problem is stuffing that many people in one place, because even if we’re playing in a common room with big tables, fitting eight-ten people there is not easy. If it’s a normal room, then it gets difficult over two participants.

A high-power wireless network could be a solution, but apparently the structure of the building is inappropriate for that. At home, i could sit in the living room with my laptop and browse the net via the shared connection of the desktop computer – with at least two walls in the way. Here it’s not working, even though people can see the network, for some reason they can not connect.

Or, a virtual network. The most popular is definitely Hamachi, which i use as well. It doesn’t take much: install the little program, join the network and it’s as if we were connected via lan. True, the speed depends on the internet connection and even then quite limited, for games it’s still all right. Also, voip programs like Ventrilo can provide the speech freedom that even lan games lack (you can’t go shouting “hey he’s alone let’s gank him!” with all the enemy sitting around you). Setting up a Ventrilo server is easy as well, i managed in about ten minutes with downloading and configuring. Also, it works across Hamachi-like virtual networks.

Also, there won’t really be a chance once we move out of the dorm and will live far away from each other.

WPA, WEP, tovább is van, mondjam még?

Tegnap délelőtt maat-nak hála be tudtam állítani a vezeték nélküli hálókártyámat Ubuntu alatt. Már kezdtem volna örülni, de csak naiv voltam. Sikerült ugyan a kártyát telepíteni, de azt elfelejtettem, hogy Windows alatt is fél napos tortúra normálisan beállítani a hálózatot (amint azt később megtapasztaltam). Linux alatt természetesen, teljesen idegen környezetben, lényegében minden segítség nélkül csak odáig sikerült jutnom, hogy az “iwlist scan” paranccsal megbizonyosodtam róla, hogy van a hálózat, látja is, de kapcsolódni hozzá nem sikerült sehogy se. Hiába állítottam be 64 bites WEP kulcsot, hiába csináltam lényegében akármit, csak nem akarták megszólítani egymást.