diff -r 93410e5e4ad8 tools/examples/xend-config.sxp
--- a/tools/examples/xend-config.sxp	Sat May 22 06:36:41 2010 +0100
+++ b/tools/examples/xend-config.sxp	Mon May 24 16:49:10 2010 +0200
@@ -110,6 +110,8 @@
 # Address xend should listen on for relocation-socket connections, if
 # xend-relocation-server is set.
 # Meaning and default as for xend-address above.
+# Also, interface name is allowed (e.g. eth0) there to get the
+# relocation address to be bound on.
 #(xend-relocation-address '')
 
 # The hosts allowed to talk to the relocation port.  If this is empty (the
diff -r 93410e5e4ad8 tools/python/xen/web/tcp.py
--- a/tools/python/xen/web/tcp.py	Sat May 22 06:36:41 2010 +0100
+++ b/tools/python/xen/web/tcp.py	Mon May 24 16:49:10 2010 +0200
@@ -21,6 +21,8 @@ import re
 import re
 import socket
 import time
+import fcntl     # For get_interface_addr
+import struct    # For get_interface_addr
 
 import connection
 
@@ -35,6 +37,49 @@ class TCPListener(connection.SocketListe
         self.hosts_allow = hosts_allow
         connection.SocketListener.__init__(self, protocol_class)
 
+    def isValidHex(self, word):
+        # If we have empty word we treat it as valid
+        if len(word) == 0:
+            return True
+        try:
+            int(word, 16)
+            return True
+        except ValueError:
+            return False
+
+    def isValidIP(self, ipaddr):
+        # Check for IPv4 address
+        numValid = 0
+        tmp = ipaddr.split('.')
+        for byte in tmp:
+            if byte.isdigit():
+                numValid += 1
+
+        if numValid == len(tmp):
+            return True
+
+        # Check for IPv6 address
+        numValid = 0
+        tmp = ipaddr.split(':')
+        for word in tmp:
+            if self.isValidHex(word):
+                numValid += 1
+
+        return numValid == len(tmp)
+
+    def getIfAddr(self, ifname):
+        s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+        try:
+            x = socket.inet_ntoa(fcntl.ioctl(
+                s.fileno(),
+                0x8915,  # SIOCGIFADDR
+                struct.pack('256s', ifname[:15])
+            )[20:24])
+            s.close()
+        except Exception, e:
+            x = ifname
+
+        return x
 
     def createSocket(self):
         sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
@@ -46,6 +91,9 @@ class TCPListener(connection.SocketListe
         timeout = time.time() + 30
         while True:
             try:
+                if not self.isValidIP(self.interface):
+                    self.interface = self.getIfAddr(self.interface)
+                log.debug("Listening on %s:%s" % (self.interface, self.port))
                 sock.bind((self.interface, self.port))
                 return sock
             except socket.error, (_errno, strerrno):
@@ -78,6 +126,49 @@ class SSLTCPListener(TCPListener):
 
         TCPListener.__init__(self, protocol_class, port, interface, hosts_allow)
 
+    def isValidHex(self, word):
+        # If we have empty word we treat it as valid
+        if len(word) == 0:
+            return True
+        try:
+            int(word, 16)
+            return True
+        except ValueError:
+            return False
+
+    def isValidIP(self, ipaddr):
+        # Check for IPv4 address
+        numValid = 0
+        tmp = ipaddr.split('.')
+        for byte in tmp:
+            if byte.isdigit():
+                numValid += 1
+
+        if numValid == len(tmp):
+            return True
+
+        # Check for IPv6 address
+        numValid = 0
+        tmp = ipaddr.split(':')
+        for word in tmp:
+            if self.isValidHex(word):
+                numValid += 1
+
+        return numValid == len(tmp)
+
+    def getIfAddr(self, ifname):
+        s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+        try:
+            x = socket.inet_ntoa(fcntl.ioctl(
+                s.fileno(),
+                0x8915,  # SIOCGIFADDR
+                struct.pack('256s', ifname[:15])
+            )[20:24])
+            s.close()
+        except Exception, e:
+            x = ifname
+
+        return x
 
     def createSocket(self):
         from OpenSSL import SSL
@@ -97,6 +188,9 @@ class SSLTCPListener(TCPListener):
         timeout = time.time() + 30
         while True:
             try:
+                if not self.isValidIP(self.interface):
+                    self.interface = self.getIfAddr(self.interface)
+                log.debug("Listening on %s:%s" % (self.interface, self.port))
                 sock.bind((self.interface, self.port))
                 return sock
             except socket.error, (_errno, strerrno):