--- ppp-2.4.5/pppd/lcp.c
+++ ppp-2.4.5/pppd/lcp.c
@@ -73,6 +73,7 @@
*/
int lcp_echo_interval = 0; /* Interval between LCP echo-requests */
int lcp_echo_fails = 0; /* Tolerance to unanswered echo-requests */
+bool lcp_echo_adaptive = 0; /* request echo only if the link was idle */
bool lax_recv = 0; /* accept control chars in asyncmap */
bool noendpoint = 0; /* don't send/accept endpoint discriminator */
@@ -151,6 +152,8 @@
OPT_PRIO },
{ "lcp-echo-interval", o_int, &lcp_echo_interval,
"Set time in seconds between LCP echo requests", OPT_PRIO },
+ { "lcp-echo-adaptive", o_bool, &lcp_echo_adaptive,
+ "Suppress LCP echo requests if traffic was received", 1 },
{ "lcp-restart", o_int, &lcp_fsm[0].timeouttime,
"Set time in seconds between LCP retransmissions", OPT_PRIO },
{ "lcp-max-terminate", o_int, &lcp_fsm[0].maxtermtransmits,
@@ -2322,6 +2325,22 @@
}
/*
+ * If adaptive echos have been enabled, only send the echo request if
+ * no traffic was received since the last one.
+ */
+ if (lcp_echo_adaptive) {
+ static unsigned int last_pkts_in = 0;
+
+ update_link_stats(f->unit);
+ link_stats_valid = 0;
+
+ if (link_stats.pkts_in != last_pkts_in) {
+ last_pkts_in = link_stats.pkts_in;
+ return;
+ }
+ }
+
+ /*
* Make and send the echo request frame.
*/
if (f->state == OPENED) {
--- ppp-2.4.5/pppd/pppd.8
+++ ppp-2.4.5/pppd/pppd.8
@@ -549,6 +549,11 @@
dynamic IP address option (i.e. set /proc/sys/net/ipv4/ip_dynaddr to
1) in demand mode if the local address changes.
.TP
+.B lcp\-echo\-adaptive
+If this option is used with the \fIlcp\-echo\-failure\fR option then
+pppd will send LCP echo\-request frames only if no traffic was received
+from the peer since the last echo\-request was sent.
+.TP
.B lcp\-echo\-failure \fIn
If this option is given, pppd will presume the peer to be dead
if \fIn\fR LCP echo\-requests are sent without receiving a valid LCP