git: b1a4ccdd8394 - main - carp: document peer/peer6 and mcast/mcast6 in the relevant man pages

The branch main has been updated by kp:

URL: https://cgit.FreeBSD.org/src/commit/?id=b1a4ccdd839431ff0e5a536a444c6e91f5858527

commit b1a4ccdd839431ff0e5a536a444c6e91f5858527
Author:     Kristof Provost <kp@FreeBSD.org>
AuthorDate: 2023-03-06 14:02:21 +0000
Commit:     Kristof Provost <kp@FreeBSD.org>
CommitDate: 2023-03-20 13:37:10 +0000

    carp: document peer/peer6 and mcast/mcast6 in the relevant man pages
    
    Sponsored by:   Rubicon Communications, LLC ("Netgate")
    Differential Revision:  https://reviews.freebsd.org/D38943
---
 sbin/ifconfig/ifconfig.8 | 18 +++++++++++++++++-
 share/man/man4/carp.4    | 19 ++++++++++++++++++-
 2 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/sbin/ifconfig/ifconfig.8 b/sbin/ifconfig/ifconfig.8
index 98d2899f1b93..4669e96e28e6 100644
--- a/sbin/ifconfig/ifconfig.8
+++ b/sbin/ifconfig/ifconfig.8
@@ -28,7 +28,7 @@
 .\"     From: @(#)ifconfig.8	8.3 (Berkeley) 1/5/94
 .\" $FreeBSD$
 .\"
-.Dd February 1, 2023
+.Dd March 6, 2023
 .Dt IFCONFIG 8
 .Os
 .Sh NAME
@@ -3086,6 +3086,22 @@ The following states are recognized:
 .Cm MASTER
 and
 .Cm BACKUP .
+.It Cm peer Ar address
+Set the address to send (IPv4)
+.Xr carp 4
+announcements to.
+.It Cm mcast
+Restore the default destination address for (IPv4)
+.Xr carp 4
+announcements, which is 224.0.0.18.
+.It Cm peer6 Ar address
+Set the address to send (IPv6)
+.Xr carp 4
+announcements to.
+.It Cm mcast6
+Restore the default destination address for (IPv4)
+.Xr carp 4
+announcements, which is ff02::12.
 .El
 .Sh ENVIRONMENT
 The following environment variables affect the execution of
diff --git a/share/man/man4/carp.4 b/share/man/man4/carp.4
index 2785b97e76ac..63fa9168dd39 100644
--- a/share/man/man4/carp.4
+++ b/share/man/man4/carp.4
@@ -26,7 +26,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd July 1, 2018
+.Dd March 6, 2023
 .Dt CARP 4
 .Os
 .Sh NAME
@@ -78,6 +78,23 @@ or through the
 .Dv SIOCSVH
 .Xr ioctl 2 .
 .Pp
+CARP defaults to using multicast messages, but can be configured to unicast
+announcements to peers using the
+.Cm peer
+and
+.Cm peer6
+parameters. Default addresses can be restored using
+.Cm mcast
+and
+.Cm mcast6 .
+Note that TTL verification is disabled if the peer address is not a multicast
+address.
+These values can be configured using
+.Xr ifconfig 8 ,
+or through the
+.Dv SIOCSPEER
+.Xr ioctl 2 .
+.Pp
 CARP virtual hosts can be configured on multicast-capable interfaces: Ethernet,
 layer 2 VLAN, FDDI and Token Ring.
 An arbitrary number of virtual host IDs can be configured on an interface.