This bug is believed to be fixed in cloud-init in version 22.3. If this
is still a problem for you, please make a comment and set the state back
to New
Thank you.
** Changed in: cloud-init
Status: Fix Committed => Fix Released
--
You received this bug notification because you are a member of Yahoo!
Engineering Team, which is subscribed to cloud-init.
https://bugs.launchpad.net/bugs/1979877
Title:
cloud-init fails with KeyError when nameserver config and matching
interface are present
Status in cloud-init:
Fix Released
Bug description:
cloud-init fails to parse network configuration with a KeyError if:
- The configuration has a `nameservers` configuration, and
- The configuration matches an existing interface on the machine, and
- The configuration name does not match that interfaces name.
Consider the following network config:
```
version: 2
ethernets:
eth:
match:
macaddress: '00:11:22:33:44:55'
addresses: [10.0.0.2/24]
gateway4: 10.0.0.1
nameservers:
addresses: [10.0.0.1]
```
Now, if a device is present with the mac address 00:11:22:33:44:55,
parsing will fail with the following stack trace:
```
2022-06-25 10:26:43,657 - util.py[WARNING]: failed stage init-local
2022-06-25 10:26:43,657 - util.py[DEBUG]: failed stage init-local
Traceback (most recent call last):
File "/usr/lib/python3/dist-packages/cloudinit/cmd/main.py", line 738, in
status_wrapper
ret = functor(name, args)
File "/usr/lib/python3/dist-packages/cloudinit/cmd/main.py", line 410, in
main_init
init.apply_network_config(bring_up=bring_up_interfaces)
File "/usr/lib/python3/dist-packages/cloudinit/stages.py", line 937, in
apply_network_config
return self.distro.apply_network_config(
File "/usr/lib/python3/dist-packages/cloudinit/distros/__init__.py", line
231, in apply_network_config
network_state = parse_net_config_data(netconfig)
File "/usr/lib/python3/dist-packages/cloudinit/net/network_state.py", line
1056, in parse_net_config_data
nsi.parse_config(skip_broken=skip_broken)
File "/usr/lib/python3/dist-packages/cloudinit/net/network_state.py", line
278, in parse_config
self.parse_config_v2(skip_broken=skip_broken)
File "/usr/lib/python3/dist-packages/cloudinit/net/network_state.py", line
328, in parse_config_v2
self._v2_common(command)
File "/usr/lib/python3/dist-packages/cloudinit/net/network_state.py", line
782, in _v2_common
self._handle_individual_nameserver(name_cmd, iface)
File "/usr/lib/python3/dist-packages/cloudinit/net/network_state.py", line
110, in decorator
return func(self, command, *args, **kwargs)
File "/usr/lib/python3/dist-packages/cloudinit/net/network_state.py", line
570, in _handle_individual_nameserver
_iface[iface]["dns"] = {"nameservers": nameservers, "search": search}
KeyError: 'eth'
```
I've investigated the issue myself and created a test case:
```
from unittest import mock
from cloudinit import safeyaml
from cloudinit.net import network_state
class TestNetDns:
@mock.patch("cloudinit.net.network_state.get_interfaces_by_mac")
def test_networkd_render_x(self, by_mac):
by_mac.return_value = {"00:11:22:33:44:55": "foobar"}
network_state.parse_net_config_data(safeyaml.load("""\
version: 2
ethernets:
eth:
match:
macaddress: '00:11:22:33:44:55'
addresses: [10.0.0.2/24]
gateway4: 10.0.0.1
nameservers:
addresses: [10.0.0.1]
"""))
```
This test case will fail with the KeyError.
The reason for this bug is that `handle_ethernets` will take the
interface name from the system because no set-name setting is present.
It will then add the network state under that interface name, not the
configured key 'eth'. Later, _handle_individual_nameserver will try to
look up the state for 'eth' and fail.
A quick bisect shows that this test case starts failing with commit
bf94945fb855c40c5188cef5fb00327c51c41fef (though the mock doesn't work
very far in the past). This commit introduced the name handling logic.
As a workaround, you can give an explicit set-name statement, or
change the key of the network config to match the physical device
name.
To manage notifications about this bug go to:
https://bugs.launchpad.net/cloud-init/+bug/1979877/+subscriptions
--
Mailing list: https://launchpad.net/~yahoo-eng-team
Post to : yahoo-eng-team@lists.launchpad.net
Unsubscribe : https://launchpad.net/~yahoo-eng-team
More help : https://help.launchpad.net/ListHelp
