`global` is needed only when assigning a new value to the global
variable; it's not necessary when modifying a mutable object (in our
case we just append items to the global list).
Otherwise, this easily trigger another exception:
```
======================================================================
ERROR: test_erspan_tunnel_v0 (__main__.NetworkdNetDevTests)
----------------------------------------------------------------------
Traceback (most recent call last):
File "./test/test-network/systemd-networkd-tests.py", line 686, in wait_online
check_output(*args, env=env)
File "./test/test-network/systemd-networkd-tests.py", line 65, in check_output
return subprocess.check_output(command, universal_newlines=True, **kwargs).rstrip()
File "/usr/lib64/python3.6/subprocess.py", line 356, in check_output
**kwargs).stdout
File "/usr/lib64/python3.6/subprocess.py", line 438, in run
output=stdout, stderr=stderr)
subprocess.CalledProcessError: Command '['/usr/lib/systemd/systemd-networkd-wait-online', '--timeout=20s', '--interface=erspan99:routable', '--interface=erspan98:routable', '--interface=dummy98:degraded']' returned non-zero exit status 1.
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "./test/test-network/systemd-networkd-tests.py", line 1808, in test_erspan_tunnel_v0
self.wait_online(['erspan99:routable', 'erspan98:routable', 'dummy98:degraded'])
File "./test/test-network/systemd-networkd-tests.py", line 689, in wait_online
output = check_output(*networkctl_cmd, '-n', '0', 'status', link.split(':')[0], env=env)
File "./test/test-network/systemd-networkd-tests.py", line 65, in check_output
return subprocess.check_output(command, universal_newlines=True, **kwargs).rstrip()
File "/usr/lib64/python3.6/subprocess.py", line 356, in check_output
**kwargs).stdout
File "/usr/lib64/python3.6/subprocess.py", line 438, in run
output=stdout, stderr=stderr)
subprocess.CalledProcessError: Command '['/usr/bin/networkctl', '-n', '0', 'status', 'erspan99']' returned non-zero exit status 1.
```
Not sure when the issue was fixed.
- kernel-3.10 on CentOS 7 has the issue,
- kernel-4.18 on CentOS 8 works fine.
Note, the workaround dropped by the commit is not incomplete:
with an old kernel which has the issue, all non-prefix routes are
configured on the specified route table, but the prefix route is
configured on the main table. That should not work for most cases,
hence, the workaround is mostly meaningless.
There is no reason networkd refuses that. Especially, when multiple
downstream interfaces are connected to the same network, it is natural to
assign the same subnet prefix to them.
Prompted by #22571.
If we assign our own test runner, passing arguments stops working
as unittest won't instantiate its own test runner after it parses
the arguments from sys.argv.
Consequence is that the tests will write to stderr now instead of
stdout since it doesn't seem possible to configure the stream that
unittest.main() will instantiate its test runner with so it'll
default to sys.stderr.
Add the "Isolated" parameter in the *.network file, e.g.,
[Bridge]
Isolated=true|false
When the Isolated parameter is true, traffic coming out of this port
will only be forward to other ports whose Isolated parameter is false.
When Isolated is not specified, the port uses the kernel default
setting (false).
The "Isolated" parameter was introduced in Linux 4.19.
See man bridge(8) for more details.
But even though the kernel and bridge/iproute2 recognize the "Isolated"
parameter, systemd-networkd did not have a way to set it.
The warning is correct, since we don't inherit the necessary
unittest.TestCase class, but that's on purpose, since the Utilities
class is not supposed to be instantiated on its own, but should
complement other classes' definitions which do inherit from the
unittest.TestCase class.
It currently works because `\(` and `\)` are not valid escape sequences,
so they're not treated differently. Using raw strings (or double
backslashes) is a more correct solution.
Multiline comments are converted to docstrings only when they're the
first statement in a function/method. Even though they're still a no-op
otherwise, let's use "true" comments to make pylint happy.
