From f80f7f0d82eaf05e68419c7ac87bf5d4c934b796 Mon Sep 17 00:00:00 2001 From: Ryan Harper Date: Thu, 26 Sep 2019 19:52:02 +0000 Subject: sysconfig: only write resolv.conf if network_state has DNS values If an OS image provided an /etc/resolv.conf file that was not empty cloud-init would read and re-write it with a cloud-init header even if no DNS network configuration was provided (e.g. DHCP only). This can cause problems for some network services which don't ignore cloud-init's header. LP: #1843634 --- tests/unittests/test_net.py | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'tests') diff --git a/tests/unittests/test_net.py b/tests/unittests/test_net.py index a093cf10..b6597412 100644 --- a/tests/unittests/test_net.py +++ b/tests/unittests/test_net.py @@ -2701,6 +2701,10 @@ USERCTL=no ns = network_state.parse_net_config_data(CONFIG_V1_EXPLICIT_LOOPBACK) render_dir = self.tmp_path("render") os.makedirs(render_dir) + # write an etc/resolv.conf and expect it to not be modified + resolvconf = os.path.join(render_dir, 'etc/resolv.conf') + resolvconf_content = "# Original Content" + util.write_file(resolvconf, resolvconf_content) renderer = self._get_renderer() renderer.render_network_state(ns, target=render_dir) found = dir2dict(render_dir) @@ -2718,6 +2722,8 @@ TYPE=Ethernet USERCTL=no """ self.assertEqual(expected, found[nspath + 'ifcfg-eth0']) + # a dhcp only config should not modify resolv.conf + self.assertEqual(resolvconf_content, found['/etc/resolv.conf']) def test_bond_config(self): expected_name = 'expected_sysconfig_rhel' @@ -3202,6 +3208,10 @@ USERCTL=no ns = network_state.parse_net_config_data(CONFIG_V1_EXPLICIT_LOOPBACK) render_dir = self.tmp_path("render") os.makedirs(render_dir) + # write an etc/resolv.conf and expect it to not be modified + resolvconf = os.path.join(render_dir, 'etc/resolv.conf') + resolvconf_content = "# Original Content" + util.write_file(resolvconf, resolvconf_content) renderer = self._get_renderer() renderer.render_network_state(ns, target=render_dir) found = dir2dict(render_dir) @@ -3219,6 +3229,8 @@ TYPE=Ethernet USERCTL=no """ self.assertEqual(expected, found[nspath + 'ifcfg-eth0']) + # a dhcp only config should not modify resolv.conf + self.assertEqual(resolvconf_content, found['/etc/resolv.conf']) def test_bond_config(self): expected_name = 'expected_sysconfig_opensuse' -- cgit v1.2.3