Iptables port 5353 -

[Bob Goodwin]

Mikkel L. Ellertson wrote:
> Bob Goodwin wrote:
>   
>> It appears that the stimulus for this is my daughters Apple Mac which
>> sends 224.0.0.251 and my computer tries to respond on port 5353.  Her
>> computer runs dhcp connecting directly via an ethernet cable to the
>> wireless router since it is on her desk.
>>
>> I guess then the question is if I open 5353 will she have access to my
>> DNS?  Is this an indication that her computer needs that access?  Would
>> it benefit?
>>
>> It's simple enough to try it but I still wont know if it accomplishes
>> anything.
>>
>> I would think she must have access to the DNS server provided by
>> Wildblue but it's been a year and a half since we set that one up and I
>> don't recall what was done and I am lost whenever I use her Mac ...
>>
>> Bob Goodwin
>>
>>     
> Let me preface this by saying that I do not run zero-config, and I
> do not have a MAC. So while I know how this is supposed to work, I
> have not verified it.
>
> If you open port 5353, what should happen is that your Linux box
> will know how to reach the MAC by using its host name. The MAC will
> be able to access the Linux box using its host name. For this to
> work, both machines have to be running the zero-config daemon. But
> it looks like they are, or you would not be getting this traffic. If
> you add a Windows machine with zero-config enabled, it will also
> show up. This does not set up other machines on the network to use
> the DNS server on your Linux machine. They will still use the DNS
> server supplied by the DHCP server. (Probably the wireless router.)
>
> For a small home network, I prefer to configure the DHCP server to
> give each machine a fixed address, and then add them to the hosts
> file for each machine. For a larger network, I like to have a Linux
> machine that is the DHCP and DNS server for the network. As part of
> that, it updates its DNS table to match assigned IP addresses. It
> also have the advantage of caching DNS entries locally, cutting down
> slightly on Internet traffic, and speeding up DNS lookups for
> machines on the local network.
>
> Mikkel
>   
I guess I need to continue looking into this then since anything that 
reduces internet activity in my present situation is a plus.  Wildblue 
has a "fair use policy," more for their benefit I suspect than for the 
users, that restricts the amount of traffic through their system [5gB 
up/17gB down/30 days] and I've been struggling to get this under control 
recently.

I have two dhcp users, the Mac and an XP, and another XP that has an 
assigned address on our home LAN.  The two dhcp's always seem to come up 
with the same addresses.  I configured the router to use 
192.168.1.21/51  and the Mac usually comes up as 22 the XP as 24.  I can 
identify them by their mac addresses and that's the way they come up. 
Curiously in the router dhcp configuration I specified that the Mac 
should be 192.168.1.21 and it gets assigned 22 while the XP was 
configured as 23 and it comes up as 24?

I need to learn more about this.  There's enough here to keep me 
confused for a while!

Thanks for the help. 

Bob Goodwin