ospfd: Fast OSPF convergence
When considering small networks that have extreme requirements on
availability and thus convergence delay, the timers given in the OSPF RFC
seem a little “conservative”, i.e., the delay between accepted LSAs and the
rate at which LSAs are sent. Cisco introduced two commands 'timers throttle
lsa all’ and 'timers lsa arrival’, which allow operators to tune these
parameters.
I have been writing a patch to also support 'timers lsa arrival’ fully and
‘timers throttle lsa all’ (without the throttling part) also in quagga.
diff --git a/ospfd/ospf_vty.c b/ospfd/ospf_vty.c
index 9d04892..e5e5631 100644
--- a/ospfd/ospf_vty.c
+++ b/ospfd/ospf_vty.c
@@ -2233,6 +2233,83 @@
return CMD_SUCCESS;
}
+DEFUN (ospf_timers_min_ls_interval,
+ ospf_timers_min_ls_interval_cmd,
+ "timers throttle lsa all <0-5000>",
+ "Adjust routing timers\n"
+ "Throttling adaptive timer\n"
+ "LSA delay between transmissions\n"
+ NO_STR
+ "Delay (msec) between sending LSAs\n")
+{
+ struct ospf *ospf = vty->index;
+ unsigned int interval;
+
+ if (argc != 1)
+ {
+ vty_out (vty, "Insufficient arguments%s", VTY_NEWLINE);
+ return CMD_WARNING;
+ }
+
+ VTY_GET_INTEGER ("LSA interval", interval, argv[0]);
+
+ ospf->min_ls_interval = interval;
+
+ return CMD_SUCCESS;
+}
+
+DEFUN (no_ospf_timers_min_ls_interval,
+ no_ospf_timers_min_ls_interval_cmd,
+ "no timers throttle lsa all",
+ NO_STR
+ "Adjust routing timers\n"
+ "Throttling adaptive timer\n"
+ "LSA delay between transmissions\n")
+{
+ struct ospf *ospf = vty->index;
+ ospf->min_ls_interval = OSPF_MIN_LS_INTERVAL;
+
+ return CMD_SUCCESS;
+}
+
+DEFUN (ospf_timers_min_ls_arrival,
+ ospf_timers_min_ls_arrival_cmd,
+ "timers lsa arrival <0-1000>",
+ "Adjust routing timers\n"
+ "Throttling link state advertisement delays\n"
+ "OSPF minimum arrival interval delay\n"
+ "Delay (msec) between accepted LSAs\n")
+{
+ struct ospf *ospf = vty->index;
+ unsigned int arrival;
+
+ if (argc != 1)
+ {
+ vty_out (vty, "Insufficient arguments%s", VTY_NEWLINE);
+ return CMD_WARNING;
+ }
+
+ VTY_GET_INTEGER_RANGE ("minimum LSA inter-arrival time", arrival, argv[0], 0, 1000);
+
+ ospf->min_ls_arrival = arrival;
+
+ return CMD_SUCCESS;
+}
+
+DEFUN (no_ospf_timers_min_ls_arrival,
+ no_ospf_timers_min_ls_arrival_cmd,
+ "no timers lsa arrival",
+ NO_STR
+ "Adjust routing timers\n"
+ "Throttling link state advertisement delays\n"
+ "OSPF minimum arrival interval delay\n")
+{
+ struct ospf *ospf = vty->index;
+ ospf->min_ls_arrival = OSPF_MIN_LS_ARRIVAL;
+
+ return CMD_SUCCESS;
+}
+
DEFUN (ospf_timers_throttle_spf,
ospf_timers_throttle_spf_cmd,
"timers throttle spf <0-600000> <0-600000> <0-600000>",
@@ -7289,6 +7366,14 @@
ospf->ref_bandwidth / 1000, VTY_NEWLINE);
}
+ /* LSA timers */
+ if (ospf->min_ls_interval != OSPF_MIN_LS_INTERVAL)
+ vty_out (vty, " timers throttle lsa all %d%s",
+ ospf->min_ls_interval, VTY_NEWLINE);
+ if (ospf->min_ls_arrival != OSPF_MIN_LS_ARRIVAL)
+ vty_out (vty, " timers lsa arrival %d%s",
+ ospf->min_ls_arrival, VTY_NEWLINE);
+
/* SPF timers print. */
if (ospf->spf_delay != OSPF_SPF_DELAY_DEFAULT ||
ospf->spf_holdtime != OSPF_SPF_HOLDTIME_DEFAULT ||
@@ -7700,6 +7785,12 @@
install_element (OSPF_NODE, &ospf_area_import_list_cmd);
install_element (OSPF_NODE, &no_ospf_area_import_list_cmd);
+ /* LSA timer commands */
+ install_element (OSPF_NODE, &ospf_timers_min_ls_interval_cmd);
+ install_element (OSPF_NODE, &no_ospf_timers_min_ls_interval_cmd);
+ install_element (OSPF_NODE, &ospf_timers_min_ls_arrival_cmd);
+ install_element (OSPF_NODE, &no_ospf_timers_min_ls_arrival_cmd);
+
/* SPF timer commands */
install_element (OSPF_NODE, &ospf_timers_spf_cmd);
install_element (OSPF_NODE, &no_ospf_timers_spf_cmd);