openbsd/net: flush the route table on net restart (canonical#908)

goneri · web-flow · commit fc161f8e3e35 · 2021-05-25T14:48:07.000-05:00
Ensure we've got a clean environment before we restart the network.

In some cases, the `sh /etc/netstart` is not enough to restart the
network. A previous default route remains in the route table and
as a result the network is broken.
Also `sh /netstart` does not kill `dhclient`.
The problen happens for instance with OVH OpenStack SBG3.
diff --git a/cloudinit/net/openbsd.py b/cloudinit/net/openbsd.py
@@ -36,6 +36,9 @@ def start_services(self, run=False):
         if not self._postcmds:
             LOG.debug("openbsd generate postcmd disabled")
             return
+        subp.subp(['pkill', 'dhclient'], capture=True, rcs=[0, 1])
+        subp.subp(['route', 'del', 'default'], capture=True, rcs=[0, 1])
+        subp.subp(['route', 'flush', 'default'], capture=True, rcs=[0, 1])
         subp.subp(['sh', '/etc/netstart'], capture=True)
 
     def set_route(self, network, netmask, gateway):
