When shutting down a Babel instance we send a wildcard retraction to make sure all peers can quickly switch to other route origins. Add another small optimisation borrowed from babeld: sending a Hello message (along with the retraction) with a very low interval. This will cause neighbours to modify their expiry timers for the node's state to quickly time it out, thus conserving resources in the network. Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk> --- proto/babel/babel.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/proto/babel/babel.c b/proto/babel/babel.c index 174fc9e26654..4c7f70c3ff66 100644 --- a/proto/babel/babel.c +++ b/proto/babel/babel.c @@ -842,14 +842,14 @@ babel_send_ihus(struct babel_iface *ifa) } static void -babel_send_hello(struct babel_iface *ifa) +babel_send_hello(struct babel_iface *ifa, uint interval) { struct babel_proto *p = ifa->proto; union babel_msg msg = {}; msg.type = BABEL_TLV_HELLO; msg.hello.seqno = ifa->hello_seqno++; - msg.hello.interval = ifa->cf->hello_interval; + msg.hello.interval = interval ?: ifa->cf->hello_interval; TRACE(D_PACKETS, "Sending hello on %s with seqno %d interval %t", ifa->ifname, msg.hello.seqno, (btime) msg.hello.interval); @@ -1557,7 +1557,7 @@ babel_iface_timer(timer *t) if (now_ >= ifa->next_hello) { - babel_send_hello(ifa); + babel_send_hello(ifa, 0); ifa->next_hello += hello_period * (1 + (now_ - ifa->next_hello) / hello_period); } @@ -1604,7 +1604,7 @@ babel_iface_start(struct babel_iface *ifa) tm_start(ifa->timer, 100 MS); ifa->up = 1; - babel_send_hello(ifa); + babel_send_hello(ifa, 0); babel_send_wildcard_retraction(ifa); babel_send_wildcard_request(ifa); babel_send_update(ifa, 0); /* Full update */ @@ -2417,6 +2417,11 @@ babel_iface_shutdown(struct babel_iface *ifa) { if (ifa->sk) { + /* + * Retract all our routes and lower the hello interval so peers' neighbour + * state expires quickly + */ + babel_send_hello(ifa, BABEL_TIME_UNITS); babel_send_wildcard_retraction(ifa); babel_send_queue(ifa); } -- 2.36.0