Hi folks! I have encountered a rather weird problem and I hope I will at least hear some ideas on how to fix it.
There is a wireless router/adsl modem (Vodafone HG556a HW.C) and two laptops. Laptop A: ASUS X73S with WIN7 ULT and Mint 13 in dual-boot and laptop B: HP Copmaq CQ43 with WIN7 ULT and SuSe 12.1 in dual-boot.
The issue: When (and only when) laptop A starts Windows and then laptop B starts SuSe my ADSL link goes down. If both A and B are running both Windows or Linux at the same time the connection to the internet is just fine on both machines. When A is running Mint and B is running Windows - no problem too. If I first start SuSe on B and then Windows on A - no problem until Linux on B is rebooted. Laptop B has been away for 5 months and before that there was no such a problem. The person who has been using it has hardly ever, if at all, run SuSe as she is an average user and got used to Windows. Now I can reproduce the failure 100% of the time. When laptop A or B is working alone - no problem too no matter what OS.
It’s like the modem refuses to work when SuSe on B and Windows on A are attempting to access the web simultaneously. I am a beginner network engineer myself, have done CompTIA Linux+ exam recently, so I’m kinda not a complete newbie in Linux and networking. I don’t know much about Vodafone modems but as far as know no router or modem is aware of higher-level OSI processes or operating systems running on our computers.
I installed all the latest updates for SuSe 12.1, but the problem persists. Any ideas, please? You are my first point of contact, the 2nd and the last I guess will be Vodafone’s tech support but I don’t really count on them.
Sorry for any mistakes - English isn’t my first language.
I wonder if maybe you have an IP conflict going on here? Check both machines network configurations. Are the addresses statically assigned, or via DHCP?
Hi, thanks for replying. All 4 OSs have DHCP enabled and DHCP is enabled on router with the range of 192.168.1.2-100 - more then enough. In fact, there is no conflict with IP-addresses since router’s web-interface is accessible from both machines at any time in any OS, it also shows me both computers connected with unique IP-addresses each. Wireless connection never goes down. But ADSL link from router to my ISP goes down same moment I attempt to establish wireless connection (I set all OSs to not connect at startup) from B using SuSe if (and only if) I have already Windows connected to the Internet on A. After that neither of laptops can access the web.
Just to clarify what I call “ADSL link goes down” is when the router’s ADSL led goes flashing and router reports through web-interface that ADSL connection is interrupted and attempts to re-establish it. It is never successful unless I shut down SuSe on laptop B. And like I said it’s not a random glitch. I am able to reproduce this situation always.
On 2012-12-24 02:16, KYTX wrote:
> Just to clarify what I call “ADSL link goes down” is when the router’s
> ADSL led goes flashing and router reports through web-interface that
> ADSL connection is interrupted and attempts to re-establish it. It is
> never successful unless I shut down SuSe on laptop B. And like I said
> it’s not a random glitch. I am able to reproduce this situation always.
Oh… (very baffled)
–
Cheers / Saludos,
Carlos E. R.
(from 11.4, with Evergreen, x86_64 “Celadon” (Minas Tirith))
Can you try using a wired connection for one of the computers, with the other connection via wlan? Does that present the same connection issue?
Some online searching regarding your router suggests that there has been some firmware issues with this hardware, so you may be best to contact your provider for support.
Just tried static IPs with A-Win-B-SuSe and A-Win-B-Win. In the former combination there is no change - it is still not working. However, I must note that when router loses ADSL link it becomes completely unresponsive. Maybe it was once or twice (that’s why first I said that it responds) but I never thoroughly checked that. Although, when ADSL link is up and running the router web-interface is available from both machines.
The latter combination (both Windows) there is a change: ADSL link up and running, but only A can access the web. B can only see the router but nothing beyond it. I tried URLs and IP-addresses (thought it might be DNS-related issue) but it won’t load a web-page or ping anything. addresses that I gave were 192.168.1.10 and 20/24 for A and B respectively.
Now I am going to try A-Mint-B-Windows and A-Mint-B-SuSe with all statics and see how it works. And then I’ll try using UTP cable.
To summarize DHCP theory - I tried all 4 combinations with static IPs and it didn’t bring any changes. Same issue arises when A is running Windows and B is running SuSe. Now about using ethernet - when I connected B via Ethernet and A via WiFi (A-Win-B-SuSe) both computers can access the web. I was aware of some software issues (like FTP not being able to recognize national characters in filenames on connected storage) but I don’t really understand how it is at all possible that a software error in a router affects only certain OSs. Do Linux and Windows produce different IP-packets? I think they don’t. Can you please share with us your findings about Vodafone’s firmware bugs?
@KYTX. As a short intermission: you can stop fumbling with the Shift key in your tedious work to type “SuSE”. It is “openSUSE”. But I admit that typing the name of the product we use correctly will not magicaly resolve your problem
Performance problems may also occur if the TCP “MTU” setting on the home broadband router differs from the setting on individual devices connected to it.
Hi everyone. I e-mailed my provider about the problem and they suggested me calling them (seems kinda weird to me). I’ll do that after Christmas and New Year holidays. Probably around 5-7th of January. My router doesn’t offer MTU change options, but it works with Windows 7 with its default MTU of 1500 bytes. I can check MTU size on the other machine in a few hours. If it’s not 1500, I’ll try adjusting it…not too sure though, if MTU in Windows is same as MTU in openSUSE. Oh, by the way the other person and their laptop are going back away on the 13th of January and they aren’t gonna be back anytime soon, so I will not be able to test possible solutions after that date.
I don’t remember where but I read that in some network devices MTU is the size of the whole IP packet and in the others it’s the size of IP-packet contents (excluding the header), or that sort of difference. I just googled MTU and this was one of the top results.
/etc/sysconfig/network/ifcfg-wlan0 file had no value for MTU (neither for pretty much everything else). Set it to 1500 - did no good. Will try to get to Vodafone’s support tonight. They told me via e-mail that it looks like firmware issue. Anyway I’m going to install Mint 13 on second machine and see if it will have the same problem…
Still it’s very strange because 5 months ago everything worked…
I guess we just should close this thread. I don’t have the laptop B around anymore anyway. Before it was gone I installed Mint 13 and it was working allright with Windows 7 and Mint 13 on laptop A.
