def _make_bridge_setup(self, name):
try:
self._make_group_fwd_mask_setup(name)
except OSError as e:
raise exc.SystemCompatibilityError(
type(self), name,
'filed to alter {} file: {}'.format(e.filename, e.strerror))
def _make_group_fwd_mask_setup(self, name):
p = pathlib.Path('/sys/class/net')
p /= name
p /= 'bridge/group_fwd_mask'
with p.open('w+') as stream:
raw = stream.readline()
bitmask = raw.strip()
try:
bitmask = int(bitmask, 0)
except ValueError as e:
raise exc.SystemCompatibilityError(
type(self), name,
'{!r} read from group_fwd_mask is not a number'.format(
raw))
bitmask |= 0x4000 # allow LLDP forwarding (ie 01:80:c2:00:00:0e)
stream.seek(0, os.SEEK_SET)
stream.write('0x{:x}\n'.format(bitmask))