If the new 'parent' keyword is specified for a host in a table,

inherit the state from another host with the specified Id; no
additional check will be for the inheriting host.  This helps in
scenarios with lots of IP aliases that all point to the same service
on the same host (like web hosting with many SSL domains).

discussed with pyr, tested in different setups

1 files changed, 14 insertions, 3 deletions

diff --git a/usr.sbin/relayd/relayd.conf.5 b/usr.sbin/relayd/relayd.conf.5
index 16c609b0f69..2611a531000 100644
--- a/usr.sbin/relayd/relayd.conf.5
+++ b/usr.sbin/relayd/relayd.conf.5
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: relayd.conf.5,v 1.88 2008/06/11 18:21:20 reyk Exp $
+.\"	$OpenBSD: relayd.conf.5,v 1.89 2008/07/19 10:52:32 reyk Exp $
 .\"
 .\" Copyright (c) 2006, 2007 Reyk Floeter <reyk@openbsd.org>
 .\" Copyright (c) 2006, 2007 Pierre-Yves Ritschard <pyr@openbsd.org>
@@ -15,7 +15,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: June 11 2008 $
+.Dd $Mdocdate: July 19 2008 $
 .Dt RELAYD.CONF 5
 .Os
 .Sh NAME
@@ -183,7 +183,7 @@ The table can be later enabled through
 .El
 Each table must contain at least one host;
 multiple hosts are separated by newline, comma, or whitespace.
-Host entries may be defined with the following attribute:
+Host entries may be defined with the following attributes:
 .Bl -tag -width retry
 .It Ic retry Ar number
 The optional retry option adds a tolerance for failed host checks;
@@ -192,6 +192,17 @@ the check will be retried for
 more times before setting the host state to down.
 If this table is used by a relay, it will also specify the number of
 retries for outgoing connection attempts.
+.It Ic parent Ar number
+The optional parent option allows to inherit the state from a parent
+host with the specified identifier.
+The check will be skipped for this host and copied from the parent host.
+This can be used to prevent multiple checks on hosts with multiple IP
+addresses for the same service.
+The host identifiers are sequentially assigned to the configured hosts
+starting with 1; it can be figured out with the
+.Xr relayctl 8
+.Ic show summary
+commands.
 .El
 .Pp
 For example: