I have a problem with my laptop resolving DNS names that only seems to be present when I am connected to my Belkin N router from home. At work, I can get online just fine, in fact, I am posting from it right now. When I open any internet page by DNS name, it states that the page cannot be found. However, when I open network tools and lookup a url (lets use google.com) I successfully pull up its internet IP address. I can then put that IP into the web browser and even search Google until I have to use a link that requires DNS. It doesn’t seem to matter if I am using wireless or wired connections. Also, other microsoft computers in the home are connecting to the net without an issue(of corse). DNS works because I can ping yahoo and lookup ip addresses from network tools, but I cannot surf the net or connect to repos. HELP!
- speretz,
you say you open a console and type “ping www.google.com” and it works, but going to “http://www.google.com” in a web browser doesn’t? If so: Which browser?
Uwe
All browsers, I have tested Opera, Firefox, and Konqueror. Also, to be 100% clear, I cannot browse “Http://www.google.com” but “http://74.125.67.100/” works great.
-----NEW DEVELOPMENT-----
I have bypassed my router and plugged straight into my AT&T DSL modem, got a valid IP and have the exact same problem. I remember an ATT support tech once telling me to set my MTU to something specific for a good connection, anyone think that this might be the problem? (Not entirely sure what the MTU does)
Also, I am not using a different computer to resolve “google.com” to an IP so buckesfeld, yes, you are correct.
speretz wrote:
> Also, I am not using a different computer to resolve “google.com” to an
> IP so buckesfeld, yes, you are correct.
>
>
VERY strange…if i understand you correctly you can ping google.com
and in that way see the IP, right?
well, let me ask, does your router and ISP provide Domain Name Server
(DNS) by way of Dynamic Host Configuration Protocol (DHCP, a protocol
for automating the configuration of computers that use TCP/IP)
if so, and you go YaST > root pass > Network Services > DNS and Hostnames
do you there see that you have checked to use DHCP?
and, is your router configured to do the same?
or maybe you are required to UNcheck the DHCP block and fill in the
ISP specified nameservers…
which way does your ISP require…
–
palladium
Have a lot of fun…
I have a couple of options, all of which work on my windows PCs.
Typically, all of my settings are established via DHCP and typically I use my router as my main DNS server. As a troubleshooting step, I have manually configured my IP settings and pointed to the ATT dns server and it gave the same results. I still have to ping google.com to find out its IP so I can use it to search.
I have also checked my /etc/resolv.conf file and it is accurate.
Also, my connection “just works” when I take it up to my office on my corporate network.
> Also, my connection “just works” when I take it up to my office on my
> corporate network.
which means to me that the trouble at home is in how your openSUSE box
is working with your router, or not…
i don’t know how to troubleshoot that…
does your YaST > Network Services > Hostnames
have 127.0.0.1 as localhost?
and, have you followed (carefully) your router’s setup routine and
added your machine’s name, IP and MAC Address and etc to the router’s
routing/WAN table, and etc???
–
palladium
Have a lot of fun…
On Tue, 03 Nov 2009 16:06:01 +0000, speretz wrote:
> Also, my connection “just works” when I take it up to my office on my
> corporate network.
Are you familiar with using tools like network sniffers (say, Wireshark)?
If you are, a trace should tell you the whole story. 
Jim
Jim Henderson
openSUSE Forums Moderator
hi,
This could be a symptom of an incorrect mtu setting…
try the following:
ping -s 1472 Tux-IT Open Source - BSD and Linux Solutions
If the pings are allowed through without a fragmentation error then all is well and your mtu is 1500.
If not then post the result back (you will get fragmentation errors if the mtu is incorrect).
Also can you post your resolv.conf and the output of the following:
ifconfig -a
route
ta
hth
J
- speretz wrote, On 11/03/2009 04:16 PM:
> Also, I am not using a different computer to resolve “google.com” to an
> IP so buckesfeld, yes, you are correct.
Try disabling IP-V6 in Yast.
Uwe
Wow, thanks guys for all the help.
palladium- the loopback is in my hostname window and my ip settings have been properly setup as far as my router is concerned
hendersj- Downloading wireshark today to see what it tells me, but no I haven’t ever really used one.
buckesfeld- Done that already
tuxituk - I think we are on to something, I am getting fragmented pings. When I hit the tuxituk site, it fragments the first couple of times, then it’s ok. When I tried opensuse.org, I never got a successful ping.
PING Tux-IT Open Source - BSD and Linux Solutions (87.194.100.100) 1472(1500) bytes of data.
From 192.168.1.254: icmp_seq=1 Frag needed and DF set (mtu = 1492)
From 192.168.1.254 icmp_seq=1 Frag needed and DF set (mtu = 1492)
1480 bytes from 87-194-100-100.bethere.co.uk (87.194.100.100): icmp_seq=2 ttl=49 time=176 ms
1480 bytes from 87-194-100-100.bethere.co.uk (87.194.100.100): icmp_seq=3 ttl=49 time=176 ms
1480 bytes from 87-194-100-100.bethere.co.uk (87.194.100.100): icmp_seq=4 ttl=49 time=175 ms
1480 bytes from 87-194-100-100.bethere.co.uk (87.194.100.100): icmp_seq=5 ttl=49 time=175 ms
1480 bytes from 87-194-100-100.bethere.co.uk (87.194.100.100): icmp_seq=6 ttl=49 time=176 ms
1480 bytes from 87-194-100-100.bethere.co.uk (87.194.100.100): icmp_seq=7 ttl=49 time=175 ms
1480 bytes from 87-194-100-100.bethere.co.uk (87.194.100.100): icmp_seq=8 ttl=49 time=176 ms
1480 bytes from 87-194-100-100.bethere.co.uk (87.194.100.100): icmp_seq=9 ttl=49 time=180 ms
1480 bytes from 87-194-100-100.bethere.co.uk (87.194.100.100): icmp_seq=10 ttl=49 time=185 ms
^C
— Tux-IT Open Source - BSD and Linux Solutions ping statistics —
11 packets transmitted, 9 received, +2 errors, 18% packet loss, time 24035ms
rtt min/avg/max/mdev = 175.701/177.648/185.816/3.171 ms, pipe 2
PING opensuse.org (130.57.5.70) 1472(1500) bytes of data.
From 192.168.1.254: icmp_seq=1 Frag needed and DF set (mtu = 1492)
From 192.168.1.254 icmp_seq=1 Frag needed and DF set (mtu = 1492)
From 192.168.1.254 icmp_seq=22 Frag needed and DF set (mtu = 1492)
^C
eth0 Link encap:Ethernet HWaddr 00:1E:EC:71:07:B8
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
Memory:e8000000-e8020000
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:14 errors:0 dropped:0 overruns:0 frame:0
TX packets:14 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:820 (820.0 b) TX bytes:820 (820.0 b)
pan0 Link encap:Ethernet HWaddr BE:A5:CD:AD:8D:16
BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
wlan0 Link encap:Ethernet HWaddr 00:21:5C:2B:27:6B
inet addr:192.168.2.6 Bcast:192.168.2.255 Mask:255.255.255.0
inet6 addr: fe80::221:5cff:fe2b:276b/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1263 errors:0 dropped:0 overruns:0 frame:0
TX packets:412 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:458251 (447.5 Kb) TX bytes:193242 (188.7 Kb)
wmaster0 Link encap:UNSPEC HWaddr 00-21-5C-2B-27-6B-32-62-00-00-00-00-00-00-00-00
UP RUNNING MTU:0 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.2.0 * 255.255.255.0 U 2 0 0 wlan0
default . 0.0.0.0 UG 0 0 0 wlan0
Had this same problem, here are a couple of notes:
- Disabling IP-V6 in yast doesn’t work, there is a bug out there for it but you need to add a boot option which I can not remember and not at that computer right now.
- Once IP-V6 was disabled, almost everything worked (browsing etc). BUT
tools like ssh and wget would not resolve host names, so that brings me to the next point… - Edit resolv.conf to put in your ISP addresses it should work, did the trick for me! I don’t know if its the router or the dsl modem that is causing my issues (netopia modem, linksys wireless router) but it works now.
Hope this helps, just google for the bug above for disabling ip-v6 with opensuse and you should find it.
Also, you can check if it really is disabled by running ifconfig, you shouldn’t see any v6 addresses there.
speretz wrote:
> tuxituk - I think we are on to something, I am getting fragmented
> pings. When I hit the tuxituk site, it fragments the first couple of
> times, then it’s ok. When I tried opensuse.org, I never got a
> successful ping.
>
> From 192.168.1.254: icmp_seq=1 Frag needed and DF set (mtu = 1492)
> [snip] PING opensuse.org (130.57.5.70) 1472(1500) bytes of data.
i’m not sure this is your problem, but you try the following and then
back out the changes if it doesn’t work:
determine and set MTU:
so, pick something smaller than 1492
ping -c 1 -s 1492 -M do google.com
keep decreasing until there is no fragmentation
then to set, become root and do
ifconfig eth0 mtu 1490
TWO notes on that command:
-use 1490 or whatever you learned was the highest no frag MTU
-command assumes only one network card (0)
live with it a while…to make that permanent:
add/change MTU=‘1490’ in /etc/sysconfig/network/ifcfg-eth0 (IF it is
ethernet card zero)
OR gui:YaST > root pass > Network Devices > Network Card > Overview
(tab) > Configure > General (tab) and change/fill in the MTU blank
with 1490, then Finish
OR YaST => System => /etc/sysconfig Editor => Hardware => Network =>
<Choose interface> (in this case eth0) => MTU
–
palladium
Have a lot of fun…
The boot parameter is ipv6.disable=1
For more reference look at this bug
https://bugzilla.novell.com/show_bug.cgi?id=539869
On Wed, 04 Nov 2009 14:06:01 +0000, speretz wrote:
> hendersj- Downloading wireshark today to see what it tells me, but no I
> haven’t ever really used one.
If you have a background in IT type work, then you should be able to pick
it up pretty easily - though it is a complex piece of software.
Basically what you’ll want to do is capture (make sure you’ve selected
the correct interface - you will need to run it as root) all traffic to
and from your machine. Start the capture, do what’s failing, and then
stop the capture. Repeat these steps in the situation where the
operation succeeds. That’ll give you something to compare to.
Chances are that you’ll see some sort of error condition on the not-
working trace (Wireshark is really good in that it makes errors really
visible - whether it’s a bad reply, a corrupted response, or packet
loss), and that should help us figure out what the problem is.
Jim
–
Jim Henderson
openSUSE Forums Moderator
PROBLEM SOLVED!!!
Thanks for the wireshark tip. It looks like a really cool program that I will be able to use a lot.
When I was told to google the boot command to disable ipv6 I found a suse help file to disable ipv6 and it went through disabling in the /etc/sysconfig editor. I followed the KDE instructions even though I am using Gnome and BIGNO, all is well.
Now time to conquer my compiz issues… again
NEVERMIND
I cannot connect to repos. Any of them. I can browse to them in firefox without a problem, but not with yast. I ran wireshark on it and it tells me definitively that it cannot resolve download.opensuse.org, but it is only for yast. I am lost…
On Thu, 05 Nov 2009 02:06:02 +0000, speretz wrote:
> PROBLEM SOLVED!!!
>
> Thanks for the wireshark tip. It looks like a really cool program that
> I will be able to use a lot.
Great news, and I’m glad that helped.
Jim
–
Jim Henderson
openSUSE Forums Moderator
On Thu, 05 Nov 2009 02:36:01 +0000, speretz wrote:
> I ran wireshark on it and it tells
> me definitively that it cannot resolve download.opensuse.org, but it is
> only for yast. I am lost…
Are you seeing responses from the DNS server?
Jim
–
Jim Henderson
openSUSE Forums Moderator
- speretz,
maybe you missed a place where IP V6 needs to be disabled. With openSUSE 11 it should be as easy as disabling it in the NIC configuration in Yast.
Uwe