[Samba] nmblookup receives response, but doesn't show it

Jeremy Allison jra at samba.org
Mon Jun 12 20:35:33 GMT 2006

On Mon, Jun 12, 2006 at 08:27:52PM +0000, Bryan K. Wright wrote:
> Hi folks,
> 	I find that nmblookup seems to be receiving 
> responses to name queries, but ignoring them.  Here's what's
> happening:
> 	# nmblookup somehost
> 	querying somehost on x.y.255.255
> 	name_query failed to find name somehost
> But watching the transaction with ethereal on the local
> host, I see that:
> 1.  nmblookup on local udp port nnnn (some random number above 1024) 
>     sends an nbns packet to udp port 137 on the broadcast address
> 2.  "somehost" immediately responds with an appropriate packet
>     from port 137 on somehost, directed at port nnnn on the local host.
>     This packet contains the correct IP address of somehost.
> Nonetheless, nmblookup acts as though it never received anything,
> and retries the request two more times before giving up.  (Each of
> the additional tries also results in a correct response from
> somehost.)
> 	iptables isn't the culprit, since I'm allowing anything
> with a dport or sport of udp 137.  (Also, I wouldn't even
> be seeing these packets with ethereal if they were blocked.)
> 	What's going on here?  It looks like nmblookup is
> just choosing to ignore the responses.

You can always check by running under gdb and seeing
if it wakes up on the response. 


More information about the samba mailing list