MAAS configures nodes with incorrect DNS server addresses when using multiple IP addresses
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
MAAS |
Fix Released
|
Undecided
|
Christian Grabowski |
Bug Description
MAAS version 2.9.2-9164-
172.17.100.0/23 (eth0, default node network)
172.17.102.0/24 (eth1, management network for IPMI etc.)
Both are untagged subnets on fabric-0 and MAAS provides DHCP. Because of that the MAAS server has two IP addresses, one on each subnet, let's say 172.17.100.3 and 172.17.102.3. When I deploy a node with static IP address (which is only on the 172.17.100.0/23 subnet) both 172.17.100.3 and 172.17.102.3 end up as nameservers in /etc/netplan/
I recently set up two additional rack controllers with the same setup (one IP on 17.100 and one on 172.102) and that makes things even worse because now there are six nameserver addresses of which three are not reachable
for machines on the 17.100 subnet. Systemd circumvents the problem but on other setups where there is an actual limit of 3 nameservers this might lead to DNS being completely broken.
This is not a problem when DHCP is used. I checked the DHCP response and that only contains the addresses on the 17.100 subnet.
Related branches
- Alberto Donato (community): Approve
- MAAS Lander: Approve
-
Diff: 136 lines (+125/-0)1 file modifiedsrc/maasserver/tests/test_preseed_network.py (+125/-0)
description: | updated |
Changed in maas: | |
assignee: | nobody → Christian Grabowski (cgrabowski) |
Changed in maas: | |
status: | New → Triaged |
Changed in maas: | |
milestone: | none → 3.0.0-rc1 |
status: | Triaged → Fix Committed |
Changed in maas: | |
status: | Fix Committed → Fix Released |
PS: this might look like a duplicate of https:/ /bugs.launchpad .net/maas/ +bug/1744454 at first. But note that in my case MAAS has IP addresses on two different subnets, and it blends nameserver information together instead of keeping it separate for each subnet.
I just noticed that this isn't a problem with DHCP, but actually only happens when setting a static IP address in the node config and deploying. Then all six IP addresses end up in /etc/netplan/ 50-cloud- init.yaml, but via DHCP I only get the ones on 172.17.100 as it should be. So something must go wrong when MAAS composes the config for cloud-init I guess.