Merge pull request #4317 from smitterl/fix_utils_net

utils_net: improve dhcpcd support

Author: nanli1

virttest/utils_net.py

@@ -1692,6 +1692,24 @@ def get_guest_nameserver(session):
     return output
 
 
+def _deactivate_ipv4ll_dhcpcd(session):
+    """
+    The command is more prone to requesting link local addresses, such as
+    169.254.200.199 and the guest ends up with two ipv4 addresses.
+    As this can lead to ipv4 discovery issues in this module and is
+    different from the previous behavior when using dhclient, deactivate it.
+
+    :param session: guest console session
+    """
+    cmd = "grep -qxF 'noipv4ll' /etc/dhcpcd.conf "
+    cmd += "|| echo 'noipv4ll' >> /etc/dhcpcd.conf"
+    status, _ = utils_misc.cmd_status_output(
+        cmd, shell=True, ignore_status=True, session=session
+    )
+    if status:
+        raise exceptions.TestError("Couldn't deactivate IPv4 local link setting.")
+
+
 def get_dhcp_client(session):
     """
     Return the available dhcp client command and its release argument.
@@ -1709,6 +1727,8 @@ def get_dhcp_client(session):
             "which %s" % cmd, shell=True, ignore_status=True, session=session
         )
         if status == 0:
+            if cmd == "dhcpcd":
+                _deactivate_ipv4ll_dhcpcd(session)
             return cmd, release_flag
 
     raise exceptions.TestError("No dhcp client found on the system")
@@ -1732,13 +1752,13 @@ def restart_guest_network(
         if mac_addr:
             nic_ifname = get_linux_ifname(session, mac_addr)
             restart_cmd = "ifconfig %s up; " % nic_ifname
-            restart_cmd += "%s; " % release_flag
+            restart_cmd += "%s %s; " % (dhcp_cmd, release_flag)
             if ip_version == "ipv6":
                 restart_cmd += "%s -6 %s" % (dhcp_cmd, nic_ifname)
             else:
                 restart_cmd += "%s %s" % (dhcp_cmd, nic_ifname)
         else:
-            restart_cmd = "%s; " % release_flag
+            restart_cmd += "%s %s; " % (dhcp_cmd, release_flag)
             if ip_version == "ipv6":
                 restart_cmd += "%s -6" % dhcp_cmd
             else: