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<p>Good Morning,</p>
<p>I am running Ubuntu 24.04, Kea 2.4.1. I have been using Kea
without major issues for a year or two, isc-dhcp for a couple of
years prior. During recent kernel updates I decided I was sick of
Virtualbox compatibility issues, so I created a bridged network so
that I could move my vms (Nextcloud, Stork) to KVM. I am somewhat
incompetent, but after about 100 attempts I have managed to setup
a bridged network that connects my server to the rest of the
network and to the internet. My new KVM VMs are joining the
network as if they were real devices. My problem is my kea DHCP4
server. I guess have done something stupid, either with selecting
the interface in kea-dhcp4.conf or with configuring my bridged
network (br0). At this stage, when I start kea-dhcp4-server, it
communicates to my HA standby to to take control of DHCP but then
completely fails to provide ip addresses itself. So, the network
currently looks like this:</p>
<p><i>dad@<a class="moz-txt-link-freetext" href="macserver:~$">macserver:~$</a> ip a<br>
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue
state UNKNOWN group default qlen 1000<br>
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00<br>
inet 127.0.0.1/8 scope host lo<br>
valid_lft forever preferred_lft forever<br>
inet6 ::1/128 scope host noprefixroute <br>
valid_lft forever preferred_lft forever<br>
2: enp34s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500
qdisc fq_codel master br0 state UP group default qlen 1000<br>
link/ether 2c:<a class="moz-txt-link-freetext" href="f0:5d:2d:88:35">f0:5d:2d:88:35</a> brd <a class="moz-txt-link-freetext" href="ff:ff:ff:ff:ff:ff">ff:ff:ff:ff:ff:ff</a><br>
3: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc
noqueue state UP group default qlen 1000<br>
link/ether 42:4c:23:6c:4d:7f brd <a class="moz-txt-link-freetext" href="ff:ff:ff:ff:ff:ff">ff:ff:ff:ff:ff:ff</a><br>
inet 192.168.1.104/23 brd 192.168.1.255 scope global
noprefixroute br0<br>
valid_lft forever preferred_lft forever<br>
inet6 <a class="moz-txt-link-freetext" href="fe80::e54c:73f4:f662:95fb/64">fe80::e54c:73f4:f662:95fb/64</a> scope link noprefixroute <br>
valid_lft forever preferred_lft forever<br>
4: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500
qdisc noqueue state DOWN group default qlen 1000<br>
link/ether 52:54:00:5b:<a class="moz-txt-link-freetext" href="e6:4e">e6:4e</a> brd <a class="moz-txt-link-freetext" href="ff:ff:ff:ff:ff:ff">ff:ff:ff:ff:ff:ff</a><br>
inet 192.168.100.1/24 brd 192.168.100.255 scope global
virbr0<br>
valid_lft forever preferred_lft forever<br>
5: vnet0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc
noqueue master br0 state UNKNOWN group default qlen 1000<br>
link/ether <a class="moz-txt-link-freetext" href="fe:00:27:dc:06:7e">fe:00:27:dc:06:7e</a> brd <a class="moz-txt-link-freetext" href="ff:ff:ff:ff:ff:ff">ff:ff:ff:ff:ff:ff</a><br>
inet6 <a class="moz-txt-link-freetext" href="fe80::fc00:27ff:fedc:67e/64">fe80::fc00:27ff:fedc:67e/64</a> scope link <br>
valid_lft forever preferred_lft forever<br>
6: vnet1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc
noqueue master br0 state UNKNOWN group default qlen 1000<br>
link/ether <a class="moz-txt-link-freetext" href="fe:54:00:80:eb:73">fe:54:00:80:eb:73</a> brd <a class="moz-txt-link-freetext" href="ff:ff:ff:ff:ff:ff">ff:ff:ff:ff:ff:ff</a><br>
inet6 <a class="moz-txt-link-freetext" href="fe80::fc54:ff:fe80:eb73/64">fe80::fc54:ff:fe80:eb73/64</a> scope link <br>
valid_lft forever preferred_lft forever</i></p>
<p>The key sections (eliminating all my lease reservations and such)
of my dhcp4.conf look like this:</p>
<p><i>{<br>
"Dhcp4": {<br>
"interfaces-config": {<br>
"interfaces": [ "br0" ]<br>
},<br>
"control-socket": {<br>
"socket-type": "unix",<br>
"socket-name": "/run/kea/kea4-ctrl-socket"<br>
},<br>
"lease-database": {<br>
"type": "memfile",<br>
"lfc-interval": 3600<br>
},<br>
"multi-threading": {<br>
"enable-multi-threading": true,<br>
"thread-pool-size": 2,<br>
"packet-queue-size": 14<br>
},<br>
"client-classes": [<br>
{<br>
"name": "homeauto"<br>
},<br>
{<br>
"name": "normal",<br>
"test": "not member('homeauto')"<br>
}<br>
],<br>
"option-data": [<br>
{<br>
"space": "dhcp4",<br>
"name": "domain-name",<br>
"code": 15,<br>
"data": "skfaf.servesarcasm.com"<br>
},<br>
{<br>
"space": "dhcp4",<br>
"name": "domain-name-servers",<br>
"code": 6,<br>
"data": "192.168.1.1"<br>
},<br>
{<br>
"space": "dhcp4",<br>
"name": "broadcast-address",<br>
"code": 28,<br>
"data": "192.168.1.255"<br>
},<br>
{<br>
"space": "dhcp4",<br>
"name": "routers",<br>
"code": 3,<br>
"data": "192.168.1.1"<br>
},<br>
{<br>
"space": "dhcp4",<br>
"name": "subnet-mask",<br>
"code": 1,<br>
"data": "255.255.254.0"<br>
}<br>
],<br>
"valid-lifetime": 43200,<br>
"renew-timer": 21600,<br>
"rebind-timer": 32400,<br>
"expired-leases-processing": {<br>
"reclaim-timer-wait-time": 3600,<br>
"hold-reclaimed-time": 172800,<br>
"max-reclaim-leases": 0,<br>
"max-reclaim-time": 0<br>
}, <br>
"dhcp-ddns": {<br>
"enable-updates": false<br>
},<br>
"authoritative": true,<br>
"hooks-libraries": [<br>
{<br>
"library":
"/usr/lib/x86_64-linux-gnu/kea/hooks/libdhcp_lease_cmds.so"<br>
},<br>
{<br>
"library":
"/usr/lib/x86_64-linux-gnu/kea/hooks/libdhcp_stat_cmds.so"<br>
},<br>
{<br>
"library":
"/usr/lib/x86_64-linux-gnu/kea/hooks/libdhcp_ha.so",<br>
"parameters": {<br>
"high-availability": [ {<br>
"this-server-name": "macserver",<br>
"mode": "hot-standby",<br>
"heatbeat-delay": 10000,<br>
"max-response-delay": 60000,<br>
"max-ack-delay": 5000,<br>
"max-unacked-clients": 5,<br>
"sync-timeout": 60000,<br>
"multi-threading": {<br>
"enable-multi-threading": true,<br>
"http-dedicated-listener": true,<br>
"http-listener-threads": 0,<br>
"http-client-threads": 0<br>
},<br>
"peers": [<br>
{<br>
"name": "macserver",<br>
"url": <a class="moz-txt-link-rfc2396E"
href="http://192.168.1.104:8003/">"http://192.168.1.104:8003/"</a>,<br>
"role": "primary"<br>
},<br>
{ <br>
"name": "oldhp",<br>
"url": <a class="moz-txt-link-rfc2396E"
href="http://192.168.1.110:8003/">"http://192.168.1.110:8003/"</a>,<br>
"role": "standby"<br>
}<br>
]<br>
} ]<br>
}<br>
}</i></p>
<p><i><br>
</i> </p>
<p><i>],<br>
"shared-networks": [<br>
{<br>
"name": "macnet",<br>
"subnet4": [<br>
{<br>
"id": 1,<br>
"subnet": "192.168.1.0/24",<br>
"pools": [<br>
{<br>
"pool": "192.168.1.124 - 192.168.1.198",<br>
"client-class": "normal"<br>
}<br>
],<br>
"option-data": [<br>
{<br>
"space": "dhcp4",<br>
"name": "routers",<br>
"code": 3,<br>
"data": "192.168.1.1"<br>
}<br>
]<br>
},<br>
{<br>
"id": 2,<br>
"subnet": "192.168.0.0/23",<br>
"pools": [<br>
{<br>
"pool": "192.168.0.150 - 192.168.0.175",<br>
"client-class": "homeauto"<br>
}<br>
],<br>
"option-data": [<br>
{<br>
"space": "dhcp4",<br>
"name": "routers",<br>
"code": 3,<br>
"data": "192.168.1.1"<br>
},<br>
{<br>
"space": "dhcp4",<br>
"name": "domain-name-servers",<br>
"code": 6,<br>
"data": "192.168.1.1"<br>
}<br>
]<br>
}<br>
]<br>
}<br>
],<br>
"loggers": [<br>
{<br>
"name": "kea-dhcp4",<br>
"output_options": [<br>
{<br>
"output": "/var/log/kea-dhcp4.log",<br>
"maxsize": 2048000,<br>
"maxver": 4<br>
}<br>
],<br>
"severity": "INFO",<br>
"debuglevel": 0<br>
}<br>
]<br>
}<br>
}</i></p>
<p><br>
</p>
<p>I changed my "interface" to "br0" because my previous setup
(exerp below) stopped working when I started the br0 network. </p>
<p> <i>{<br>
"Dhcp4": {<br>
"interfaces-config": {<br>
"interfaces": [ "enp34s0" ]</i></p>
<p>Changing the interface to "br0" has had exactly no effect.</p>
<p>I realise that I have missed something fundamental and I am
wasting your valuable time. However I have been trying to sort
this out for days (in whatever spare time is available) and I have
acheived nothing. Each time I start kea-dhcp-server on my main
server it appears in Stork with no errors, systemd says its
running fine and my HA standby stops providing dhcp. Unfortunately
if I then turn on a device it simply does not receive an ip lease.
If I turn off DHCP on the main server then eventually the standby
starts takes over dhcp again and network functions return to
normal (though this takes a very long time & sometimes
requires a restart of kea-dhcp4-server on the stanby server,
perhaps another error to fix later). Even my new VMs receive ips
seamlessly from the standby server.</p>
<p>If you need to see some logs, please tell me where I can retreive
them because I haven't been able to work that out either (I think
I need to change my logging parameters in kea-dhcp4.conf). I used
Wireshark to capture network coms before and after turning on the
main dhcp server but I then realised that I was too
stupid/ignorant to work out what was going on from the output. I
can provided the Wireshark output, but it is a large file (ran it
for too long and filtered it poorly, I think) that I won't inflict
on you unless you wish it.</p>
<p>Please give me some ideas of what I have to do to
troubleshoot/fix this.</p>
<p>Regards</p>
<p>Stuart MacGregor</p>
<p><br>
</p>
<p><br>
</p>
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