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On Mon, May 23, 2022 at 09:06PM +0200,
Geert Stappers <<a href="mailto:stappers@stappers.nl">stappers@stappers.nl</a>>
wrote:
<div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">On Mon, May 23, 2022 at 08:11:53PM +0200, Kamil wrote:<br>
> On Wed, May 18, 2022 at 10:14, Geert Stappers via Dnsmasq-discuss wrote:<br>
> > On Tue, May 17, 2022 at 11:16:28AM +0200, Kamil via Dnsmasq-discuss wrote:<br>
> > > On Mon, May 16, 2022 at 04:56:25PM +0100, Simon Kelley wrote:<br>
> > > ><br>
> > > > What does the output of<br>
> > > ><br>
> > > > iptables -L<br>
> > > ><br>
> > > > look like?<br>
> > > ><br>
> > > # iptables -L<br>
> > > Chain INPUT (policy ACCEPT)<br>
> > > target prot opt source destination<br>
> > ><br>
> > > Chain FORWARD (policy ACCEPT)<br>
> > > target prot opt source destination<br>
> > ><br>
> > > Chain OUTPUT (policy ACCEPT)<br>
> > > target prot opt source destination<br>
> ><br>
> > Acknowledge on those firewall (empty) rules.<br>
> ><br>
> <br>
> Dear Geert,<br>
> <br>
> Is there something I should change?<br>
> <br></blockquote><div><br></div><div>
Dear Geert,
</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<br>
Not on the firewall rules.<br>
<br>
} Is there something I should change?<br>
<br>
Yes<br>
<br>
> | # tcpdump -i eth0<br>
<br>
Add a filter (stop flooding us )<br>
a filter to try<br>
ether host 38:XX:XX:XX:XX:c3 or port bootps<br>
So the command line with filter<br>
tcpdump -i eth0 ether host 38:XX:XX:XX:XX:c3 or port bootps<br>
<br>
<br>
Use another character as > <br>
example given |<br>
so another character as what email client use for "previous text"<br></blockquote><div><br></div><div>
Of course! <br></div><div>I'm sorry for flooding previously.
</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<br>
Example<br>
> | tcpdump: verbose output suppressed, use -v[v]... for full protocol decode<br>
> | listening on eth0, link-type EN10MB (Ethernet), snapshot length 262144 bytes<br></blockquote><div><br></div><div><br></div><div>Here is the filtered tcpdump:</div><div><br></div><div>| # tcpdump -i eth0 port bootps<br>| tcpdump: verbose output suppressed, use -v[v]... for full protocol decode<br>| listening on eth0, link-type EN10MB (Ethernet), snapshot length 262144 bytes<br>| <br>| [All devices unplugged. Plugging Device X]<br>| <br>| 14:16:53.674021 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from 38:XX:XX:XX:XX:c3 (oui Unknown), length 548<br>| 14:16:59.174249 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from 38:XX:XX:XX:XX:c3 (oui Unknown), length 548<br>| 14:17:02.179593 IP 192.168.6.1.bootps > 25250484.bootpc: BOOTP/DHCP, Reply, length 300<br>| 14:17:02.180817 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from 38:XX:XX:XX:XX:c3 (oui Unknown), length 548<br>| 14:17:02.198161 IP 192.168.6.1.bootps > 25250484.bootpc: BOOTP/DHCP, Reply, length 300<br>| <br>| [Unplugging Device X]<br>| [Unplugged]<br>| [Plugging RTMU86]<br>| <br>| 14:17:41.901105 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:ZZ:ZZ:ZZ:ZZ:1c (oui Unknown), length 300<br>| 14:17:44.978012 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:ZZ:ZZ:ZZ:ZZ:1c (oui Unknown), length 300<br>| 14:18:05.667274 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:ZZ:ZZ:ZZ:ZZ:1c (oui Unknown), length 300<br>| 14:18:08.747191 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:ZZ:ZZ:ZZ:ZZ:1c (oui Unknown), length 300<br>| 14:18:29.659678 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:ZZ:ZZ:ZZ:ZZ:1c (oui Unknown), length 300<br>| 14:18:32.737700 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:ZZ:ZZ:ZZ:ZZ:1c (oui Unknown), length 300<br>| <br>| [Unplugging RTMU86]<br>| [Unplugged RTMU86]<br>| [Plugging Device X]<br>| <br>| 14:19:50.276363 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from 38:XX:XX:XX:XX:c3 (oui Unknown), length 548<br>| 14:19:52.686176 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from 38:XX:XX:XX:XX:c3 (oui Unknown), length 548<br>| 14:19:56.186461 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from 38:XX:XX:XX:XX:c3 (oui Unknown), length 548<br>| 14:19:56.187331 IP 192.168.6.1.bootps > 25250484.bootpc: BOOTP/DHCP, Reply, length 300<br>| 14:19:56.188564 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from 38:XX:XX:XX:XX:c3 (oui Unknown), length 548<br>| 14:19:56.202561 IP 192.168.6.1.bootps > 25250484.bootpc: BOOTP/DHCP, Reply, length 300</div><div><br></div><div><br></div><div>Moreover - I've tried isc-dhcp-server with minimal config (without "authorative" flag):</div><div><br></div><div>| subnet 192.168.6.0 netmask 255.255.255.0 {<br>| interface eth0;<br>| range 192.168.6.11 192.168.6.20;<br>| option subnet-mask 255.255.255.0;<br>| option routers 192.168.6.1;<br>| }</div><div><br></div><div>And the result of filtered tcpdump is as follows:<br></div><div><br></div><div>| # tcpdump -i eth0 port bootps<br>| tcpdump: verbose output suppressed, use -v[v]... for full protocol decode<br>| listening on eth0, link-type EN10MB (Ethernet), snapshot length 262144 bytes<br>| <br>| [All devices unplugged. Plugging Device X]<br>| <br>| 14:29:07.305369 IP 192.168.6.11.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from 38:XX:XX:XX:XX:c3 (oui Unknown), length 548<br>| 14:29:08.306388 IP 0.0.0.0.bootps > 192.168.6.11.bootpc: BOOTP/DHCP, Reply, length 300<br>| 14:29:08.307842 IP 192.168.6.11.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from 38:XX:XX:XX:XX:c3 (oui Unknown), length 548<br>| 14:29:08.308360 IP 0.0.0.0.bootps > 192.168.6.11.bootpc: BOOTP/DHCP, Reply, length 300<br>| <br>| <br>| [Unplugging Device X]<br>| [Unplugged]<br>| [Plugging RTMU86]<br>| <br>| 14:30:09.646491 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:ZZ:ZZ:ZZ:ZZ:1c (oui Unknown), length 300<br>| 14:30:10.647624 IP 0.0.0.0.bootps > 192.168.6.12.bootpc: BOOTP/DHCP, Reply, length 300<br>| 14:30:10.686487 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:ZZ:ZZ:ZZ:ZZ:1c (oui Unknown), length 300<br>| 14:30:10.702470 IP 0.0.0.0.bootps > 192.168.6.12.bootpc: BOOTP/DHCP, Reply, length 300<br></div><div><br></div><div>So IP was assigned to the RTMU86 in the same maner as for Device X<br></div><div> </div><div>Kind regards,</div><div>Kamil</div><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<br>
<br>
> > ....<br>
> ><br>
> > [Done]<br>
> <br>
> Syslog:<br>
> > ...<br>
> > Done<br>
> <br>
> As you can see - Device X got its IP assigned every time.<br>
<br>
No, because I have other stuff to look after.<br>
No, because I have other stuff to see at.<br>
<br>
<br>
> I have absolutely no idea why RTMU86 is not working...<br>
> <br>
> <br>
> > Start with analyzing the working configuration.<br>
> ><br>
> What information about the network could I provide?<br>
> <br>
> <br>
> <br>
> ><br>
> > Groeten<br>
> > Geert Stappers<br>
> ><br>
> > P.S. @Kamil: Your email client doesn't add<br>
> > On <timestamp>, <person> wrote:<br>
> > line on top of your responses.<br>
> ><br>
> <br>
> It should work now<br>
<br>
Yes, it did.<br>
Thanks for fixing it.<br>
<br>
<br>
> ><br>
> > P.S. @all: Please avoid obfuscation of what you send.<br>
> > (Please do not mangle MAC addresses)<br>
> ><br>
> <br>
> I'm sorry, I'm obligated to not publish this data<br>
> <br>
<br>
I feel sorry for you (in your current situation).<br>
<br>
<br>
<br>
Groeten<br>
Geert Stappers<br>
No hard feelings<br>
(My younger version also encountered unawareness first hand)<br>
-- <br>
Silence is hard to parse<br>
</blockquote></div></div>