Ubuntu 18.04 wrong parsing of instance-data.json generating network config

[ubuntu-server-builder]

This bug was originally filed in Launchpad as LP: #2008772

Launchpad details

affected_projects = []
assignee = None
assignee_name = None
date_closed = 2023-03-02T15:08:07.699836+00:00
date_created = 2023-02-28T10:04:38.670156+00:00
date_fix_committed = None
date_fix_released = None
id = 2008772
importance = undecided
is_complete = True
lp_url = https://bugs.launchpad.net/cloud-init/+bug/2008772
milestone = None
owner = vgobja
owner_name = Vadim Gobja
private = False
status = invalid
submitter = vgobja
submitter_name = Vadim Gobja
tags = []
duplicates = []

Launchpad user Vadim Gobja(vgobja) wrote on 2023-02-28T10:04:38.670156+00:00

Hello,

We have an cloud service based on Openstack, we have provide IPv4 (dhcp) and IPv6 (static),
on ubuntu 18.04 we detected that when is parsed instance-data.json it take info only for IPv4 and not get static records for IPv6. And related to this it not generate config for IPv6 we tested with netplan and ENI (ifupdown), all data in instance-data.json are present in the file.

2023-02-28 09:21:42,649 - util.py[DEBUG]: Reading from /sys/class/net/ens3/type (quiet=False)
2023-02-28 09:21:42,650 - util.py[DEBUG]: Read 2 bytes from /sys/class/net/ens3/type
2023-02-28 09:21:42,650 - networking.py[DEBUG]: net: all expected physical devices present
2023-02-28 09:21:42,650 - stages.py[DEBUG]: applying net config names for {'ethernets': {'ens3': {'dhcp4': True, 'set-name': 'ens3', 'match': {'macaddress': 'fa:16:3e:00:3c:33'}}}, 'version': 2}
2023-02-28 09:21:42,650 - util.py[DEBUG]: Reading from /sys/class/net/ens3/device/device (quiet=False)
2023-02-28 09:21:42,650 - util.py[DEBUG]: Read 7 bytes from /sys/class/net/ens3/device/device

On ubuntu 20.04 this problem not persist.
2023-02-27 14:36:40,755 - util.py[DEBUG]: Reading from /sys/class/net/lo/type (quiet=False)
2023-02-27 14:36:40,755 - util.py[DEBUG]: Read 4 bytes from /sys/class/net/lo/type
2023-02-27 14:36:40,755 - networking.py[DEBUG]: net: all expected physical devices present
2023-02-27 14:36:40,755 - stages.py[DEBUG]: applying net config names for {'version': 1, 'config': [{'type': 'physical', 'mtu': 1500, 'accept-ra': False, 'subnets': [{'type': 'dhcp4'}, {'type': 'static6', 'netmask': 'ffff:ffff:ffff:ffff::', 'routes': [{'network': '::', 'netmask': '::', 'gateway': '2a10:c941:12:1::1'}], 'address': '2a10:c941:12:1::10f', 'ipv6': True}], 'mac_address': 'fa:16:3e:f3:d9:ad', 'name': 'ens3'}, {'type': 'nameserver', 'address': '8.8.8.8'}, {'type': 'nameserver', 'address': '1.1.1.1'}]}
2023-02-27 14:36:40,756 - util.py[DEBUG]: Reading from /sys/class/net/ens3/device/device (quiet=False)
2023-02-27 14:36:40,756 - util.py[DEBUG]: Read 7 bytes from /sys/class/net/ens3/device/device

cloud-init version: 22.4.2-0ubuntu0~18.04.1

we tried and older version but it work same

[ubuntu-server-builder]

Launchpad user Vadim Gobja(vgobja) wrote on 2023-02-28T10:07:41.215022+00:00

Launchpad attachments: Ubuntu 20.04 collect log

[ubuntu-server-builder]

Launchpad user Vadim Gobja(vgobja) wrote on 2023-02-28T10:08:12.191100+00:00

Launchpad attachments: Ubuntu 18.04 collect log

[ubuntu-server-builder]

Launchpad user Vadim Gobja(vgobja) wrote on 2023-02-28T10:09:07.854874+00:00

Attached and the collected logs from Ubuntu 18.04 and 20.04.

[ubuntu-server-builder]

Launchpad user James Falcon(falcojr) wrote on 2023-03-02T15:07:54.443595+00:00

This is expected behavior. On Ubuntu 18.04, on Openstack, the network was configured using the fallback network interface only. In Ubuntu 20.04, it was updated to use network_data.json. Since changing this behavior would have resulted in backwards incompatibly, it is not default behavior on 18.04.

To enable this behavior on 18.04, you can add the following to /etc/cloud/cloud.cfg or a file in /etc/cloud/cloud.cfg.d/

datasource:
OpenStack:
apply_network_config: true

Since this is expected behavior, I'm going to set this bug status to Invalid, but if I have missed something, please do set it back to New and add more context.

See the following links for context:
https://bugs.launchpad.net/cloud-init/+bug/1749717
cd1de5f
https://github.com/canonical/cloud-init/blob/ubuntu/bionic/debian/patches/openstack-no-network-config.patch/

[ubuntu-server-builder]

Launchpad user Vadim Gobja(vgobja) wrote on 2023-03-03T08:21:48.369371+00:00

Thank for reply, missed this in documentation.