[ale] Fedora 13 DNS weirdness

[Joe Knapka]

Thanks, Brian, I will try disabling IPv6.  I'll also try stracing both 
telnet and ping
on my home network and on my SO's network, and compare the results.


On 08/09/2010 06:42 PM, Brian Pitts wrote:
> On 08/08/2010 11:05 PM, Joe Knapka wrote:
>    
>> I went to my SO's house, configured the wifi connection for her network,
>> and it connected with no problem.  I could ping the router and the
>> upstream gateway by IP or by name.  I could ping things out in the world
>> by name:
>>
>>     jk at jaklaptop:>  ping google.com
>> <successful ping responses from an actual Google IP>
>>
>> However, other applications that I tried (FireFox, telnet, ssh) did this
>> (or in FF's case gave me the equivalent "I can't do that" page):
>>
>>     jk at jaklaptop:>  telnet google.com 80
>>     Host google.com not found - Name or service unknown.
>>
>> Weirdly, dig and nslookup had no problem resolving google.com (or any
>> other name). But any app that I actually wanted to USE for any practical
>> purpose complained about name lookup errors, as in the telnet example above.
>>
>> I checked everything in Network Manager and the two networks were
>> configured identically. I looked at /etc/resolv.conf, /etc/host.conf,
>> /etc/nsswitch.conf and everything looked totally OK -- the machine was
>> using the correct router and DNS server for my SO's network. I ran
>> tcpdump on UDP port 53 while doing a ping and a telnet, and I saw
>> successful DNS requests for google.com in both cases.... but telnet
>> still complained about "Name or service unknown". I thought maybe it was
>> something to do with SELinux, so I disabled that, but no joy.
>>      
> I might try
>
> strace -v -e trace=network telnet google.com 80
>
> to see things from telnet's perspective.
>
> Also, I might try disabling ipv6.
>
> Do the /bin/true thing described below, then reboot.
>
> http://www.cyberciti.biz/faq/redhat-centos-disable-ipv6-networking/
>
>