Make sasyncd fail back correctly with carp preemption enabled.

Hold the carp demotion when booting, to prevent carp from preempting until
we've sync'd with our peers.  This adds a new CTL_ENDSNAP message to the
exchange between the sasync daemons to indicate when the complete snapshot
has been sent. Undemote after 60 seconds, or when recieve a CTL_ENDSNAP from
all our peers.

Syntax is slightly changed, removing the 'carp' keyword (so do
"interface carp0" rather than "carp interface carp0". Adds 'group <ifgroup>',
defaults to the 'carp' group.

ok moritz@

1 files changed, 21 insertions, 1 deletions

diff --git a/usr.sbin/sasyncd/net_ctl.c b/usr.sbin/sasyncd/net_ctl.c
index 811ed648ba5..fcd346a0ad5 100644
--- a/usr.sbin/sasyncd/net_ctl.c
+++ b/usr.sbin/sasyncd/net_ctl.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: net_ctl.c,v 1.7 2006/06/01 22:43:12 mcbride Exp $	*/
+/*	$OpenBSD: net_ctl.c,v 1.8 2006/06/02 20:09:43 mcbride Exp $	*/
 
 /*
  * Copyright (c) 2005 Håkan Olsson.  All rights reserved.
@@ -50,6 +50,8 @@ struct ctlmsg {
 	u_int32_t	data2;
 };
 
+int snapcount = 0;
+
 static int
 net_ctl_check_state(struct syncpeer *p, enum RUNSTATE nstate)
 {
@@ -89,6 +91,18 @@ net_ctl_handle_msg(struct syncpeer *p, u_int8_t *msg, u_int32_t msglen)
 	}
 
 	switch (ntohl(ctl->type)) {
+	case CTL_ENDSNAP:
+		log_msg(4, "net_ctl: got CTL_ENDSNAP from peer \"%s\"",
+		    p->name);
+
+		/* XXX More sophistication required to handle multiple peers. */
+		if (carp_demoted) {
+			snapcount++;
+			if (snapcount >= cfgstate.peercnt)
+				monitor_carpundemote(NULL);
+		}
+		break;
+
 	case CTL_STATE:
 		log_msg(4, "net_ctl: got CTL_STATE from peer \"%s\"", p->name);
 		nstate = (enum RUNSTATE)ntohl(ctl->data);
@@ -174,6 +188,12 @@ net_ctl_send_error(struct syncpeer *p, enum CTLTYPE prevtype)
 	return net_ctl_send(p, CTL_ERROR, (u_int32_t)prevtype, 0);
 }
 
+int
+net_ctl_send_endsnap(struct syncpeer *p)
+{
+	return net_ctl_send(p, CTL_ENDSNAP, 0, 0);
+}
+
 /* After a CARP tracker state change, send an state ctl msg to all peers. */
 void
 net_ctl_update_state(void)