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<p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif">Hi All,<span></span></p>
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<p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif">I have a simple setup with a relay agent as shown below:</p><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif"><br></p><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif">+----------+-------------+<br>| dnsmasq server |<br></p><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif"> | (ubuntu) |<br></p><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif">+-------------------------+ <br> | m1s1p7 (1040::2/120)<br> | (IP route : 2020::/120 via 1040::1 dev m1s1p7 proto static metric 512 pref medium)<br> |<br> | <br> | 1/1/2 (1040::1/120)<br>+----------+------------+<br>| Switch |<br>| (Relay Agent ) |<br>+-----------------------+ <br> | 1/1/1 (2020::1/120) <br> |<br> | <br> | eth1 <br>+----------+--------------+<br>| Client (Ubuntu) |<br>+--------------------------+</p><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif"><br></p><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif">
</p><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif">It is exactly the same as explained in the video : <a href="https://www.youtube.com/watch?v=2Lt1aXpCzvQ" style="color:rgb(5,99,193);text-decoration:underline">https://www.youtube.com/watch?v=2Lt1aXpCzvQ</a>
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<p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif"><span><br></span></p>
<p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif">Whenever the client is requesting an IPv6 address dnsmasq is
failing to respond with “DHCPADVERTISE” message. The “DHCPADVERTISE” has not
been sent via the interface. The tcpdump clearly shows that “DHCPADVERTISE”
message has not gone through the interface (m1s1p7), its only showing the “DHCPSOLICIT”
message which has been received:<span></span></p>
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<p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt"><i><span style="font-family:monospace,monospace">root@8320:~# tcpdump -i <b>m1s1p7</b>
udp port 547 or 546 -vvv -n<span></span></span></i></p><i><span style="font-family:monospace,monospace">
</span></i><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt"><i><span style="font-family:monospace,monospace">tcpdump: listening on m1s1p7, link-type EN10MB (Ethernet),
capture size 262144 bytes<span></span></span></i></p><i><span style="font-family:monospace,monospace">
</span></i><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt"><i><span style="font-family:monospace,monospace"> </span></i></p><i><span style="font-family:monospace,monospace">
</span></i><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif"><i><span style="font-family:monospace,monospace">06:32:37.214798 IP6 (hlim 64, next-header UDP (17) payload
length: 110) 2020::1.547 > 1040::2.547: [udp sum ok] dhcp6 relay-fwd
(linkaddr=2020::1 peeraddr=fe80::250:56ff:febd:7c93 (relay-message (<b>dhcp6 solicit</b> (xid=1894f2 (client-ID
hwaddr/time type 1 time 599811159 005056bd7c93) (option-request DNS-server
DNS-search-list Client-FQDN SNTP-servers) (elapsed-time 0) (IA_NA
IAID:1455258771 T1:3600 T2:5400))) (interface-ID 00000024...))</span></i><span></span></p>
<p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif"><span> </span></p>
<p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif">But the dnsmasq logs shows that it is trying to send the “DHCPADVERTISE”
message but for some reason it’s not been sent via the interface <b>m1s1p7. <span></span></b></p>
<p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif"><b><span> </span></b></p><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif"><b><span>
</span></b></p><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt"><i><span style="font-family:monospace,monospace">root@8320:~# tail -f /var/log/dnsmasq_swns/dnsmasq6.log<span></span></span></i></p><i><span style="font-family:monospace,monospace">
</span></i><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt"><i><span style="font-family:monospace,monospace">Jan<span> </span>3 06:11:20
dnsmasq[4151]: started, version 2.78 DNS disabled<span></span></span></i></p><i><span style="font-family:monospace,monospace">
</span></i><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt"><i><span style="font-family:monospace,monospace">Jan<span> </span>3 06:11:20
dnsmasq[4151]: compile time options: IPv6 GNU-getopt no-DBus no-i18n no-IDN
DHCP DHCPv6 no-Lua TFTP no-conntrack ipset auth no-DNSSEC loop-detect inotify<span></span></span></i></p><i><span style="font-family:monospace,monospace">
<span style="font-size:11pt">Jan<span> </span>3
06:11:20 dnsmasq-dhcp[4151]: DHCPv6, IP range 2020::10 -- 2020::20, lease time
1h</span></span></i> <br></div><div dir="ltr"><br>
<p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt"><i><span style="font-family:monospace,monospace">Jan<span> </span>3 06:12:38
dnsmasq-dhcp[4151]: DHCPSOLICIT(m1s1p7) 00:01:00:01:23:c0:64:57:00:50:56:bd:7c:93<span></span></span></i></p><i><span style="font-family:monospace,monospace">
</span></i><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif"><i><span style="font-family:monospace,monospace">Jan<span> </span>3 06:12:38
dnsmasq-dhcp[4151]: DHCPADVERTISE(m1s1p7) 2020::12
00:01:00:01:23:c0:64:57:00:50:56:bd:7c:93</span></i><span></span></p>
<p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif"><span> </span></p>
<p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif"><b>Does anyone has any clue on what is going on here ? Am I
missing something ? Here is my dnsmasq config file contents:</b><span></span></p>
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<p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt"><i><span style="font-family:monospace,monospace">root@8320:~# cat /var/run/dnsmasq_swns/dnsmasq6.conf<span></span></span></i></p><i><span style="font-family:monospace,monospace">
</span></i><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt"><i><span style="font-family:monospace,monospace">enable-ra<span></span></span></i></p><i><span style="font-family:monospace,monospace">
</span></i><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt"><i><span style="font-family:monospace,monospace">log-dhcp<span></span></span></i></p><i><span style="font-family:monospace,monospace">
</span></i><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt"><i><span style="font-family:monospace,monospace">log-queries<span></span></span></i></p><i><span style="font-family:monospace,monospace">
</span></i><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt"><i><span style="font-family:monospace,monospace">log-facility=/var/log/dnsmasq_swns/dnsmasq6.log<span></span></span></i></p><i><span style="font-family:monospace,monospace">
</span></i><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt"><i><span style="font-family:monospace,monospace">port=0<span></span></span></i></p><i><span style="font-family:monospace,monospace">
</span></i><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt"><i><span style="font-family:monospace,monospace">dhcp-script=/usr/bin/dhcp_server_leases<span></span></span></i></p><i><span style="font-family:monospace,monospace">
</span></i><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt"><i><span style="font-family:monospace,monospace">leasefile-ro<span></span></span></i></p><i><span style="font-family:monospace,monospace">
</span></i><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt"><i><span style="font-family:monospace,monospace">dhcp-lease-max=64000<span></span></span></i></p><i><span style="font-family:monospace,monospace">
</span></i><p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif"><i><span style="font-family:monospace,monospace">dhcp-range=set:default+test,2020::10,2020::20,120</span></i><span></span></p>
<p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif"><span> </span></p>
<p class="MsoNormal" style="margin:0in 0in 0.0001pt;font-size:11pt;font-family:"Calibri",sans-serif">Thanks<span></span></p>
<span style="font-size:11pt;font-family:"Calibri",sans-serif">-Sandeep</span>
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