Start managing bird2

Also give dummy-interface support to sunet-l4lb-namespace tool, used
to hold IPv4/IPv6 service addresses that should be announced via BGP.

global/overlay/etc/puppet/modules/cdn/files/l4lb/sunet-l4lb-namespace

@@ -47,7 +47,12 @@ def configure_interfaces(
             False,
         )
         if not if_exists:
-            run_command(f"ip link set {if_name} netns {namespace}")
+            if if_name.startswith("dummy"):
+                run_command(
+                    f"ip netns exec {namespace} ip link add {if_name} type dummy"
+                )
+            else:
+                run_command(f"ip link set {if_name} netns {namespace}")
 
         proc = run_command(f"ip netns exec {namespace} ip -j addr show dev {if_name}")
         if_conf = json.loads(proc.stdout)

global/overlay/etc/puppet/modules/cdn/manifests/l4lb.pp

@@ -15,6 +15,10 @@ class cdn::l4lb(
     }
   }
 
+  include sunet::systemd_reload
+
+  package {'bird2': ensure => installed }
+
   file { '/opt/sunet-cdn':
     ensure  => directory,
     owner   => 'root',
@@ -59,4 +63,20 @@ class cdn::l4lb(
     mode    => '0644',
     content => template('cdn/l4lb/sunet-l4lb-namespace.service.erb'),
   }
+
+  file { '/etc/systemd/system/bird.service.d':
+    ensure  => directory,
+    owner   => 'root',
+    group   => 'root',
+    mode    => '0755',
+  }
+
+  file { '/etc/systemd/system/bird.service.d/override.conf':
+    ensure  => file,
+    owner   => 'root',
+    group   => 'root',
+    mode    => '0644',
+    content => template('cdn/l4lb/bird-override.conf.erb'),
+    notify => [Class['sunet::systemd_reload']]
+  }
 }

global/overlay/etc/puppet/modules/cdn/templates/bird-override.conf.erb

@@ -0,0 +1,4 @@
+[Service]
+NetworkNamespacePath=/var/run/netns/l4lb
+Wants=sunet-l4lb-namespace.service
+After=sunet-l4lb-namespace.service