commit a9985a761c98c7c980d7b9f80a4737a07ae0d21a
Author: Matthew Booth <mbooth@redhat.com>
Date:   Mon May 24 10:47:33 2010 +0100

    RHEL 5: Use old ip= syntax to set slirp network

diff --git a/src/guestfs.c b/src/guestfs.c
index 027e08c..2aff72b 100644
--- a/src/guestfs.c
+++ b/src/guestfs.c
@@ -1208,7 +1208,14 @@ guestfs__launch (guestfs_h *g)
      */
     if (null_vmchannel_sock) {
       add_cmdline (g, "-net");
-      add_cmdline (g, "user,vlan=0,net=" NETWORK);
+
+      /* The slirp stack in RHEL 5's qemu-kvm only supports an old, undocumented
+       * option, ip=x.x.x.0, to modify the default network configuration.
+       * Despite being called 'ip', it actually refers to the class C network
+       * from which default IP address will be allocated. It must end in .0, or
+       * it will not work predictably. */
+      add_cmdline (g, "user,vlan=0,ip=169.254.2.0");
+      /* add_cmdline (g, "user,vlan=0,net=" NETWORK); */
 
       snprintf (buf, sizeof buf,
                 "guestfs_vmchannel=tcp:" ROUTER ":%d",