Author: Vincent Bernat <vbe@exoscale.ch>
Origin: upstream
Bug: https://launchpad.net/bugs/1382481
Applied-Upstream: yes
Description:  query virtual CloudStack router instead of default gw
 This patch is a backport of what is currently upstream.
Index: cloud-init-0.6.3/cloudinit/DataSourceCloudStack.py
===================================================================
--- cloud-init-0.6.3.orig/cloudinit/DataSourceCloudStack.py
+++ cloud-init-0.6.3/cloudinit/DataSourceCloudStack.py
@@ -20,6 +20,7 @@
 
 import cloudinit.DataSource as DataSource
 
+import os
 from cloudinit import seeddir as base_seeddir
 from cloudinit import log
 import cloudinit.util as util
@@ -87,8 +88,8 @@ class DataSourceCloudStack(DataSource.Da
     def __init__(self, sys_cfg=None):
         DataSource.DataSource.__init__(self, sys_cfg)
         # Cloudstack has its metadata/userdata URLs located at
-        # http://<default-gateway-ip>/latest/
-        self.vr_addr = self.get_default_gateway()
+        # http://<virtual-router-ip>/latest/
+        self.vr_addr = self.get_vr_address()
         if not self.vr_addr:
             raise RuntimeError("No virtual router found!")
         self.metadata_address = "http://%s/" % (self.vr_addr,)
@@ -106,6 +107,55 @@ class DataSourceCloudStack(DataSource.Da
                     log.debug("found default route, gateway is %s" % gw)
                     return gw
 
+    def get_dhclient_d(self):
+        # find lease files directory
+        supported_dirs = ["/var/lib/dhclient", "/var/lib/dhcp"]
+        for d in supported_dirs:
+            if os.path.exists(d):
+                log.debug("Using %s lease directory", d)
+                return d
+
+    def get_latest_lease(self):
+        # find latest lease file
+        lease_d = self.get_dhclient_d()
+        if not lease_d:
+            return None
+        lease_files = os.listdir(lease_d)
+        latest_mtime = -1
+        latest_file = None
+        for file_name in lease_files:
+            if file_name.endswith(".lease") or file_name.endswith(".leases"):
+                abs_path = os.path.join(lease_d, file_name)
+                mtime = os.path.getmtime(abs_path)
+                if mtime > latest_mtime:
+                    latest_mtime = mtime
+                    latest_file = abs_path
+        return latest_file
+
+    def get_vr_address(self):
+        # Get the address of the virtual router via dhcp leases
+        # see http://bit.ly/T76eKC for documentation on the virtual router.
+        # If no virtual router is detected, fallback on default gateway.
+        lease_file = self.get_latest_lease()
+        if not lease_file:
+            log.debug("No lease file found, using default gateway")
+            return self.get_default_gateway()
+
+        latest_address = None
+        with open(lease_file, "r") as fd:
+            for line in fd:
+                if "dhcp-server-identifier" in line:
+                    words = line.strip(" ;\r\n").split(" ")
+                    if len(words) > 2:
+                        dhcp = words[2]
+                        log.debug("Found DHCP identifier %s", dhcp)
+                        latest_address = dhcp
+        if not latest_address:
+            # No virtual router found, fallback on default gateway
+            log.debug("No DHCP found, using default gateway")
+            return self.get_default_gateway()
+        return latest_address
+
     def __str__(self):
         return "DataSourceCloudStack"