diff --git a/tests/_live_build.pm b/tests/_live_build.pm
index 76f48291..9e933d92 100644
--- a/tests/_live_build.pm
+++ b/tests/_live_build.pm
@@ -12,14 +12,14 @@ sub run {
     my $lcsubv = lc($subv);
     # install the tools we need
     assert_script_run "dnf -y install mock git pykickstart tar", 120;
+    # base mock config on original
+    assert_script_run "echo \"include('/etc/mock/fedora-${version}-${arch}.cfg')\" > /etc/mock/openqa.cfg";
     # make the update/task repo and the serial device available inside the mock root
-    assert_script_run 'echo "config_opts[\'plugin_conf\'][\'bind_mount_enable\'] = True" > /etc/mock/openqa.cfg';
+    assert_script_run 'echo "config_opts[\'plugin_conf\'][\'bind_mount_enable\'] = True" >> /etc/mock/openqa.cfg';
     assert_script_run 'echo "config_opts[\'plugin_conf\'][\'bind_mount_opts\'][\'dirs\'].append((\'/opt/update_repo\', \'/opt/update_repo\'))" >> /etc/mock/openqa.cfg';
     assert_script_run 'echo "config_opts[\'plugin_conf\'][\'bind_mount_opts\'][\'dirs\'].append((\'/dev/' . $serialdev . '\', \'/dev/' . $serialdev . '\'))" >> /etc/mock/openqa.cfg';
-    # now append the whole 'stock' config except for the final """ line
-    assert_script_run "head -n-1 /etc/mock/fedora-${version}-${arch}.cfg >> /etc/mock/openqa.cfg";
-    # now add the side repo to the config
-    assert_script_run 'printf "[advisory]\nname=Advisory repo\nbaseurl=file:///opt/update_repo\nenabled=1\nmetadata_expire=3600\ngpgcheck=0\n\"\"\"" >> /etc/mock/openqa.cfg';
+    # add the side repo to the config
+    assert_script_run 'printf "config_opts[\'yum.conf\'] += \"\"\"\n[advisory]\nname=Advisory repo\nbaseurl=file:///opt/update_repo\nenabled=1\nmetadata_expire=3600\ngpgcheck=0\n\"\"\"" >> /etc/mock/openqa.cfg';
     # replace metalink with mirrorlist so we don't get slow mirrors
     repos_mirrorlist("/etc/mock/openqa.cfg");
     # upload the config so we can check it's OK