[ubuntu-us-mi] hostname lookup bug?

[David F]

Is "foo" a hostname or IP address?  Are you sure that your query is going 
where you think it is going?  Are you sure that you successfully removed bar 
from DNS on foo?  Could you run "tshark -i <interface> udp and port 53" 
(where <interface> is the name of the network interface through which 
packets to foo are routed, e.g. eth0), then run the dig command, and post 
the output?  Obscure any sensitive information if you want, but be careful, 
"pseudo-commands" sometimes hide a lot.

If you see no queries/replies, check carefully that you didn't make a 
mistake with the sniffer command because as previously noted, dig should not 
do local caching.  Let's find out on which machine the problem is before 
jumping to any conclusions.

-- David

On 11/09/2010 10:52 AM, Robert Citek wrote:
> I'm trying to figure out where the issue is with name resolution on
> Ubuntu Lucid 10.04.  Here are the symptoms in psuedo-commands:
>
> on Red Hat machine:
> $ dig @foo bar
> ->  10.1.1.1
>
> on Ubuntu:
> $ dig @foo bar
> ->  10.1.1.1
>
> Remove bar from DNS on foo.
>
> on Red Hat machine:
> $ dig @foo bar
> ->  no IP
>
> on Ubuntu:
> $ dig @foo bar
> ->  10.1.1.1
>
> reboot Ubuntu machine.
> on Ubuntu:
> $ dig @foo bar
> ->  no IP
>
> Why is Ubuntu still returning an IP for machine foo?  What is being
> cleared/stopped by the reboot?
>
> I'll try to setup a self-contained real example a bit later.
>
> Regards,
> - Robert
>