summaryrefslogtreecommitdiffstats
path: root/share/man/man4/carp.4
diff options
context:
space:
mode:
authorglebius <glebius@FreeBSD.org>2005-02-24 09:43:16 +0000
committerglebius <glebius@FreeBSD.org>2005-02-24 09:43:16 +0000
commit7e63660244cf6bb6bee26f4cf6aedb8c20cf3c71 (patch)
tree7c15cf67eb9f3565ddc86ef0d0df3627ee0562db /share/man/man4/carp.4
parent64091a686c4803e6b3afbd4ab844ed833ce82092 (diff)
downloadFreeBSD-src-7e63660244cf6bb6bee26f4cf6aedb8c20cf3c71.zip
FreeBSD-src-7e63660244cf6bb6bee26f4cf6aedb8c20cf3c71.tar.gz
mdoc(7) cleanup
Submitted by: ru
Diffstat (limited to 'share/man/man4/carp.4')
-rw-r--r--share/man/man4/carp.485
1 files changed, 47 insertions, 38 deletions
diff --git a/share/man/man4/carp.4 b/share/man/man4/carp.4
index 16ebfea..35067f8 100644
--- a/share/man/man4/carp.4
+++ b/share/man/man4/carp.4
@@ -23,7 +23,7 @@
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
-.\" $FreeBSD$
+.\" $FreeBSD$
.\"
.Dd February 23, 2005
.Dt CARP 4
@@ -36,10 +36,9 @@
.Sh DESCRIPTION
The
.Nm
-interface is a pseudo-device which implements and controls the
+interface is a pseudo-device that implements and controls the
CARP protocol.
-.Nm
-allows multiple hosts on the same local network to share a set of IP addresses.
+CARP allows multiple hosts on the same local network to share a set of IP addresses.
Its primary purpose is to ensure that these
addresses are always available, but in some configurations
.Nm
@@ -48,7 +47,7 @@ can also provide load balancing functionality.
A
.Nm
interface can be created at runtime using the
-.Ic ifconfig carp Ns Ar N Ic create
+.Nm ifconfig Li carp Ns Ar N Cm create
command or by setting up configuration in
.Pa /etc/rc.conf
file.
@@ -65,29 +64,33 @@ and
which are used to control how frequently the host sends advertisements when it
is the master for a virtual host, and
.Cm pass
-which is used to authenticate carp advertisements.
+which is used to authenticate
+.Nm
+advertisements.
Finally
.Cm carpdev
is used to specify which interface the
.Nm
device attaches to.
-If unspecified, the kernel attempts to set carpdev by looking for
+If unspecified, the kernel attempts to set
+.Cm carpdev
+by looking for
another interface with the same subnet.
These configurations can be done using
.Xr ifconfig 8 ,
or through the
.Dv SIOCSVH
-ioctl.
+.Xr ioctl 2 .
.Pp
Additionally, there are a number of global parameters which can be set using
.Xr sysctl 8 :
-.Bl -tag -width net.inet.carp.arpbalance
-.It net.inet.carp.allow
+.Bl -tag -width ".Va net.inet.carp.arpbalance"
+.It Va net.inet.carp.allow
Accept incoming
.Nm
packets.
Enabled by default.
-.It net.inet.carp.preempt
+.It Va net.inet.carp.preempt
Allow virtual hosts to preempt each other.
It is also used to failover
.Nm
@@ -95,17 +98,19 @@ interfaces as a group.
When the option is enabled and one of the
.Nm
enabled physical interfaces
-goes down, advskew is changed to 240 on all
+goes down,
+.Cm advskew
+is changed to 240 on all
.Nm
interfaces.
See also the first example.
Disabled by default.
-.It net.inet.carp.log
+.It Va net.inet.carp.log
Log bad
.Nm
packets.
Enabled by default.
-.It net.inet.carp.arpbalance
+.It Va net.inet.carp.arpbalance
Balance local traffic using ARP.
Disabled by default.
.El
@@ -117,32 +122,35 @@ interfaces together, when one of the physical interfaces goes down.
This is achieved by the preempt option.
Enable it on both host A and B:
.Pp
-.Dl # sysctl net.inet.carp.preempt=1
+.Dl sysctl net.inet.carp.preempt=1
.Pp
Assume that host A is the preferred master and 192.168.1.x/24 is
configured on one physical interface and 192.168.2.y/24 on another.
This is the setup for host A:
.Bd -literal -offset indent
-# ifconfig carp0 create
-# ifconfig carp0 vhid 1 pass mekmitasdigoat 192.168.1.1 \e
+ifconfig carp0 create
+ifconfig carp0 vhid 1 pass mekmitasdigoat 192.168.1.1 \e
255.255.255.0
-# ifconfig carp1 create
-# ifconfig carp1 vhid 2 pass mekmitasdigoat 192.168.2.1 \e
+ifconfig carp1 create
+ifconfig carp1 vhid 2 pass mekmitasdigoat 192.168.2.1 \e
255.255.255.0
.Ed
.Pp
-The setup for host B is identical, but it has a higher advskew:
+The setup for host B is identical, but it has a higher
+.Cm advskew :
.Bd -literal -offset indent
-# ifconfig carp0 create
-# ifconfig carp0 vhid 1 advskew 100 pass mekmitasdigoat \e
+ifconfig carp0 create
+ifconfig carp0 vhid 1 advskew 100 pass mekmitasdigoat \e
192.168.1.1 255.255.255.0
-# ifconfig carp1 create
-# ifconfig carp1 vhid 2 advskew 100 pass mekmitasdigoat \e
+ifconfig carp1 create
+ifconfig carp1 vhid 2 advskew 100 pass mekmitasdigoat \e
192.168.2.1 255.255.255.0
.Ed
.Pp
Because of the preempt option, when one of the physical interfaces of
-host A fails, advskew is adjusted to 240 on all its
+host A fails,
+.Cm advskew
+is adjusted to 240 on all its
.Nm
interfaces.
This will cause host B to preempt on both interfaces instead of
@@ -156,34 +164,35 @@ provide balancing and failover for the IP address 192.168.1.10.
.Pp
First the
.Nm
-interfaces on Host A are configured.
+interfaces on host A are configured.
The
.Cm advskew
of 100 on the second virtual host means that its advertisements will be sent
out slightly less frequently.
.Bd -literal -offset indent
-# ifconfig carp0 create
-# ifconfig carp0 vhid 1 pass mekmitasdigoat 192.168.1.10 \e
+ifconfig carp0 create
+ifconfig carp0 vhid 1 pass mekmitasdigoat 192.168.1.10 \e
255.255.255.0
-# ifconfig carp1 create
-# ifconfig carp1 vhid 2 advskew 100 pass mekmitasdigoat \e
+ifconfig carp1 create
+ifconfig carp1 vhid 2 advskew 100 pass mekmitasdigoat \e
192.168.1.10 255.255.255.0
.Ed
.Pp
-The configuration for host B is identical, except the skew is on
-virtual host 1 rather than virtual host 2.
+The configuration for host B is identical, except the
+.Cm advskew
+is on virtual host 1 rather than virtual host 2.
.Bd -literal -offset indent
-# ifconfig carp0 create
-# ifconfig carp0 vhid 1 advskew 100 pass mekmitasdigoat \e
+ifconfig carp0 create
+ifconfig carp0 vhid 1 advskew 100 pass mekmitasdigoat \e
192.168.1.10 255.255.255.0
-# ifconfig carp1 create
-# ifconfig carp1 vhid 2 pass mekmitasdigoat 192.168.1.10 \e
+ifconfig carp1 create
+ifconfig carp1 vhid 2 pass mekmitasdigoat 192.168.1.10 \e
255.255.255.0
.Ed
.Pp
Finally, the ARP balancing feature must be enabled on both hosts:
.Pp
-.Dl # sysctl net.inet.carp.arpbalance=1
+.Dl sysctl net.inet.carp.arpbalance=1
.Pp
When the hosts receive an ARP request for 192.168.1.10, the source IP address
of the request is used to compute which virtual host should answer the request.
@@ -210,5 +219,5 @@ device first appeared in
.Ox 3.5 .
The
.Nm
-device was imported to
+device was imported into
.Fx 5.4 .
OpenPOWER on IntegriCloud