Merge pull request #49 from pguibert6WIND/frr_6wind_mpbgpgracefulrestart_2

Graceful Restart Route Preservation 

4 files changed, 37 insertions, 1 deletions

diff --git a/bgpd/bgp_open.c b/bgpd/bgp_open.c
index 4c698562be..af3c0486e5 100644
--- a/bgpd/bgp_open.c
+++ b/bgpd/bgp_open.c
@@ -1537,7 +1537,10 @@ bgp_open_capability (struct stream *s, struct peer *peer)
             {
               stream_putw (s, afi);
               stream_putc (s, (safi == SAFI_MPLS_VPN) ? SAFI_MPLS_LABELED_VPN : safi);
-              stream_putc (s, 0); //Forwarding is not retained as of now.
+              if (bgp_flag_check(peer->bgp, BGP_FLAG_GR_PRESERVE_FWD))
+                stream_putc (s, RESTART_F_BIT);
+              else
+                stream_putc (s, 0);
             }
     }
 
diff --git a/bgpd/bgp_vty.c b/bgpd/bgp_vty.c
index c691d20a87..a5fa97021e 100644
--- a/bgpd/bgp_vty.c
+++ b/bgpd/bgp_vty.c
@@ -1677,6 +1677,31 @@ DEFUN (no_bgp_graceful_restart_restart_time,
   return CMD_SUCCESS;
 }
 
+DEFUN (bgp_graceful_restart_preserve_fw,
+       bgp_graceful_restart_preserve_fw_cmd,
+       "bgp graceful-restart preserve-fw-state",
+       "BGP specific commands\n"
+       "Graceful restart capability parameters\n"
+       "Sets F-bit indication that fib is preserved while doing Graceful Restart\n")
+{
+  VTY_DECLVAR_CONTEXT(bgp, bgp);
+  bgp_flag_set(bgp, BGP_FLAG_GR_PRESERVE_FWD);
+  return CMD_SUCCESS;
+}
+
+DEFUN (no_bgp_graceful_restart_preserve_fw,
+       no_bgp_graceful_restart_preserve_fw_cmd,
+       "no bgp graceful-restart preserve-fw-state",
+       NO_STR
+       "BGP specific commands\n"
+       "Graceful restart capability parameters\n"
+       "Unsets F-bit indication that fib is preserved while doing Graceful Restart\n")
+{
+  VTY_DECLVAR_CONTEXT(bgp, bgp);
+  bgp_flag_unset(bgp, BGP_FLAG_GR_PRESERVE_FWD);
+  return CMD_SUCCESS;
+}
+
 /* "bgp fast-external-failover" configuration. */
 DEFUN (bgp_fast_external_failover,
        bgp_fast_external_failover_cmd,
@@ -9886,6 +9911,9 @@ bgp_vty_init (void)
   install_element (BGP_NODE, &bgp_graceful_restart_restart_time_cmd);
   install_element (BGP_NODE, &no_bgp_graceful_restart_restart_time_cmd);
 
+  install_element (BGP_NODE, &bgp_graceful_restart_preserve_fw_cmd);
+  install_element (BGP_NODE, &no_bgp_graceful_restart_preserve_fw_cmd);
+ 
   /* "bgp fast-external-failover" commands */
   install_element (BGP_NODE, &bgp_fast_external_failover_cmd);
   install_element (BGP_NODE, &no_bgp_fast_external_failover_cmd);
diff --git a/bgpd/bgpd.c b/bgpd/bgpd.c
index 68ad6bbe11..f9c3f9af4b 100644
--- a/bgpd/bgpd.c
+++ b/bgpd/bgpd.c
@@ -7371,6 +7371,10 @@ bgp_config_write (struct vty *vty)
       if (bgp_flag_check (bgp, BGP_FLAG_GRACEFUL_RESTART))
        vty_out (vty, " bgp graceful-restart%s", VTY_NEWLINE);
 
+      /* BGP graceful-restart Preserve State F bit. */
+      if (bgp_flag_check (bgp, BGP_FLAG_GR_PRESERVE_FWD))
+       vty_out (vty, " bgp graceful-restart preserve-fw-state%s", VTY_NEWLINE);
+
       /* BGP bestpath method. */
       if (bgp_flag_check (bgp, BGP_FLAG_ASPATH_IGNORE))
 	vty_out (vty, " bgp bestpath as-path ignore%s", VTY_NEWLINE);
diff --git a/bgpd/bgpd.h b/bgpd/bgpd.h
index 86fa207b6b..b82cf9dde9 100644
--- a/bgpd/bgpd.h
+++ b/bgpd/bgpd.h
@@ -289,6 +289,7 @@ struct bgp
 #define BGP_FLAG_MULTIPATH_RELAX_AS_SET   (1 << 17)
 #define BGP_FLAG_FORCE_STATIC_PROCESS     (1 << 18)
 #define BGP_FLAG_SHOW_HOSTNAME            (1 << 19)
+#define BGP_FLAG_GR_PRESERVE_FWD          (1 << 20)
 
   /* BGP Per AF flags */
   u_int16_t af_flags[AFI_MAX][SAFI_MAX];