wifi non connection

Pedroski · #1 8th February 2013, 01:06 AM

This is a long ongoing problem. Maybe someone has an idea. I have an ordinary dsl router with wlan at home. I cannot use the wlan under Linux. nm says I am connected (see screenshot), but there is no internet access. I have never been able to connect to the internet using the wifi at home under Linux. Works fine under Windows, but I hardly ever use Win. Recently I got an Android phone. That also cannot use the wlan to access the internet. The router is new, the isp upgraded my connection to make it faster an gave me a new router.

Here is some info which may give someone a clue as to what is wrong. Why am I getting 'REFUSED'?
1) The dsl cable is unplugged
[pedro@peterbedroom ~]$ nslookup baidu.com
Server: 192.168.1.1
Address: 192.168.1.1#53

** server can't find baidu.com: REFUSED
[pedro@peterbedroom ~]$ host google.com 192.168.1.4
;; connection timed out; trying next origin
;; connection timed out; no servers could be reached

2) The dsl cable is plugged into the laptop

[pedro@peterbedroom ~]$ nslookup baidu.com
Server: 218.2.135.1
Address: 218.2.135.1#53

Non-authoritative answer:
Name: baidu.com
Address: 123.125.114.144
Name: baidu.com
Address: 220.181.111.85
Name: baidu.com
Address: 220.181.111.86

[pedro@peterbedroom ~]$

3) I ran nslookup baidu.com with the dsl cable unplugged and at the same time ran tcpdump. Here is the output of tcpdump.

[pedro@peterbedroom ~]$ sudo tcpdump -i wlan0 -vn port 53
tcpdump: listening on wlan0, link-type EN10MB (Ethernet), capture size 65535 bytes
08:44:32.924987 IP (tos 0x0, ttl 64, id 22233, offset 0, flags [none], proto UDP (17), length 55)
192.168.1.4.38925 > 192.168.1.1.domain: 41931+ A? baidu.com. (27)
08:44:32.928814 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto UDP (17), length 55)
192.168.1.1.domain > 192.168.1.4.38925: 41931 Refused 0/0/0 (27)
08:44:32.931827 IP (tos 0x0, ttl 64, id 22234, offset 0, flags [none], proto UDP (17), length 55)
192.168.1.4.56955 > 192.168.1.1.domain: 54745+ A? baidu.com. (27)
08:44:32.933899 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto UDP (17), length 55)
192.168.1.1.domain > 192.168.1.4.56955: 54745 Refused 0/0/0 (27)
^C
4 packets captured
4 packets received by filter
0 packets dropped by kernel
[pedro@peterbedroom ~]$

This says refused. If I run tcpdump with a lot of tabs open in Firefox, they are all 'Refused'

Does anyone know what is happening here? Why is the router refusing to connect to the internet? I can access the router, but I cannot see a setting to unblock/block internet access. It seems strange to have a wlan set to no access. Pointless having wlan then.

Any ideas out there??

christian_l · #2 8th February 2013, 06:08 AM

Since you also have problems with your Android phone, I would guess that the problem lies with the router. Try to connect with your WiFi, then log into the router and see if it has a log that tells you why it just refused your connection. You might also see some error message in /var/log/messages (as root).

Also, compare the details of your working WiFi setup on Windows with the one on Linux, and see if you can find some difference between the two (manual vs automatic DHCP, DNS servers, MAC address...).

Pedroski · #3 8th February 2013, 08:55 AM

This is from my son's laptop connected via wlan under Win. The dns is also 192.168.1.1 The difference is, it works!

Wireless LAN adapter Wireless Network Connection:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Broadcom 802.11g Network Adapter
Physical Address. . . . . . . . . : 0C-EE-E6-BC-A3-4A
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
Link-local IPv6 Address . . . . . : fe80::6d74:f3c0:7d3c:1f65%10(Preferred)
IPv4 Address. . . . . . . . . . . : 192.168.1.5(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Lease Obtained. . . . . . . . . . : 06 February 2013 17:46:01
Lease Expires . . . . . . . . . . : 09 February 2013 17:46:01
Default Gateway . . . . . . . . . : 192.168.1.1
DHCP Server . . . . . . . . . . . : 192.168.1.1
DHCPv6 IAID . . . . . . . . . . . : 185396966
DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-13-CD-AD-2B-00-26-22-85-F3-68

DNS Servers . . . . . . . . . . . : 192.168.1.1
NetBIOS over Tcpip. . . . . . . . : Enabled

sidebrnz · #4 14th February 2013, 02:13 AM

I've told you in another thread to find out exactly how the working connection is configured and copy all of the details to the one that isn't and see if that works. Until you've done that, I have no more suggestions.

Pedroski · #5 14th February 2013, 03:24 AM

Put it this way: at home , Linux, Android and iPhone say 'There is a wlan available, please input the password' then 'I am connected to router' BUT they cannot access the internet. Windows also says 'I am connected to the internet' BUT until we make the dsl connection, notwithstanding that the dsl cable is not plugged into the laptop, then and only then can windows connect via wlan to the internet. That is a crucial difference to Linux, and I fear, the source of my problem. You can clearly see above that the router is sending back 'REFUSED'

I am slowly coming to the conclusion that this router is hardwired to reject normal wlan requests. They have rigged it to accept windows wlan requests, because most of China uses windows.

At the office I don't do anything special, just click on our available wlan and enter the password. Nothing else, and it works!

sidebrnz · #6 14th February 2013, 03:48 AM

Since you won't try what I've suggested (copy the appropriate parts of your Windows settings on Linux) I have nothing more to say. Do as you wish and don't bother me unless you're willing to try what I've told you, or you have and it hasn't worked.

Pedroski · #7 14th February 2013, 03:58 AM

Really, there is nothing to copy. Just the password in the appropriate place. Fedora says it is connected. I do not do anything else in the office. I can't do anything else here. There is nothing I can alter, except the password and the name of the network, and even that must start with ChinaNet-

Above is the output from the working windows connection: I cannot put that in Fedora, I would not know how or where!!

Pedroski · #8 14th February 2013, 04:02 AM

Here is an nm screenshot taken just now: tell me how that is different to windows.

flyingfsck · #9 14th February 2013, 06:07 AM

Howdy,

To use a network, you need four things:
IP address
Network Mask
Default Route
Domain Name Server

Your problem likely lies with either the default route or the DNS settings.

Check the IP address and mask using the ifconfig command
Check the route using the route command
Check the DNS settings using dig or nslookup

Pedroski · #10 14th February 2013, 06:19 AM

So, a happy end!!

2 days ago, my internet tv suddenly stopped working. I got a girl to call the helpline and just now a man came to have a look. I mentioned that my phone and my laptop cannot connect to the wlan. He said, no, you have to enable wlan, by putting your username and password (ie my area code plus phone number, then just phone number)

He used my laptop and connected to the net, then entered 192.168.1.1 BUT: he did not enter the useradmin and the password written on the back of the router. He used telecomadmin and some other long password! He then had a completely different 192.168.1.1 page, and the details were entered in seconds!

Now I can write this without using the cable connection!! So sorry to have caused you any bother, but I've had 3 years of no wifi at home! I was getting frustrated!

All this still leaves me wondering why Windows can manage the wlan connection without the wlan enabled in this way. Windows must push the username and password from the dsl connection to the wlan page somehow!! I wish Linux would learn that trick.

Thanks again and sorry to have troubled you!!