cloud-init crashes with IPv6 routes

[ubuntu-server-builder]

This bug was originally filed in Launchpad as LP: #2014226

Launchpad details

affected_projects = []
assignee = None
assignee_name = None
date_closed = None
date_created = 2023-03-31T21:37:48.042949+00:00
date_fix_committed = 2023-04-05T21:59:44.610594+00:00
date_fix_released = 2023-04-05T21:59:44.610594+00:00
id = 2014226
importance = undecided
is_complete = False
lp_url = https://bugs.launchpad.net/cloud-init/+bug/2014226
milestone = None
owner = mcamilli
owner_name = Michael Camilli
private = False
status = incomplete
submitter = mcamilli
submitter_name = Michael Camilli
tags = ['docs']
duplicates = []

Launchpad user Michael Camilli(mcamilli) wrote on 2023-03-31T21:37:48.042949+00:00

I have static routes specified for two networks, and during cloud-init an error occurs as it tries to make use of NETMASK1.

Network 2

eth1:
addresses: # List of IP[v4,v6] addresses to assign to this interface
- 2001:db8:abcd:abce:fe::1000/96

routes: # List of static routes for this interface
  - to: 2001:db8:abcd:abce:fe::0/96
    via: 2001:db8:abcd:bbce:fe::2

Network 3

eth2:
addresses: # List of IP[v4,v6] addresses to assign to this interface
- 2001:db8:abcd:abcf:fe::1000/96

routes: # List of static routes for this interface
  - to: 2001:db8:abcd:abcf:fe::0/96
    via: 2001:db8:abcd:bbcf:fe::2

Traceback (most recent call last):
File "/usr/lib/python3.6/site-packages/cloudinit/cmd/main.py", line 761, in status_wrapper
ret = functor(name, args)
File "/usr/lib/python3.6/site-packages/cloudinit/cmd/main.py", line 433, in main_init
init.apply_network_config(bring_up=bring_up_interfaces)
File "/usr/lib/python3.6/site-packages/cloudinit/stages.py", line 926, in apply_network_config
netcfg, bring_up=bring_up
File "/usr/lib/python3.6/site-packages/cloudinit/distros/init.py", line 233, in apply_network_config
self._write_network_state(network_state)
File "/usr/lib/python3.6/site-packages/cloudinit/distros/init.py", line 129, in _write_network_state
renderer.render_network_state(network_state)
File "/usr/lib/python3.6/site-packages/cloudinit/net/sysconfig.py", line 1011, in render_network_state
base_sysconf_dir, network_state, self.flavor, templates=templates
File "/usr/lib/python3.6/site-packages/cloudinit/net/sysconfig.py", line 1002, in _render_sysconfig
contents[cpath] = iface_cfg.routes.to_string(proto)
File "/usr/lib/python3.6/site-packages/cloudinit/net/sysconfig.py", line 199, in to_string
netmask_value = str(self._conf["NETMASK" + index])
KeyError: 'NETMASK1'

Additional Info:

1. Using KVM on a private server
2. See above configuration details that cause an issue. Note in the documentation I could only find an example of an ipv4 route, so maybe you could enhance the documentation with an example for ipv6 if possible.

[ubuntu-server-builder]

Launchpad user Michael Camilli(mcamilli) wrote on 2023-03-31T21:37:48.042949+00:00

Launchpad attachments: cloud-init.tar.gz

[ubuntu-server-builder]

Launchpad user Chad Smith(chad.smith) wrote on 2023-04-05T21:59:37.597357+00:00

Thanks for filing a bug and making cloud-init better and for the documentation request plug as well.
I'm adding a docs tag to the bug so it could be looked at from a documentation standpoint as well.

This bug looks conspicuously like the former bug https://bugs.launchpad.net/cloud-init/+bug/1958506 which was fixed in cloud-init version 22.2. If possible, would you be able to try reproducing this issue with a newer version of cloud-init?

You may be able to install cloud-init upstream's latest approved upstream release of 23.1 from our copr repo
https://copr.fedorainfracloud.org/coprs/g/cloud-init/el-testing/packages/

Once cloud-init is upgraded to 23.1 try running sudo cloud-init clean --logs --reboot to force cloud-init to try to reconfigure the system and network from scratch across reboot. If the KeyError still persists, then we know this is a new bug and not one formerly fixed.
I'm marking it 'incomplete' status above. Please set back to 'New' if you get a chance to confirm that latest cloud-init 23.1 still exhibits this issue.

[igalic]

https://bugs.launchpad.net/cloud-init/+bug/1958506 is now #3940

[holmanb]

This is believed to be fixed. Please reopen if you believe this to still be an issue.