IFDEPD(8) BSD System Manager's Manual IFDEPD(8)NAME
ifdepd — Interface Dependancy daemon
SYNOPSIS
ifdepd [-v|q] [-d] -S src-if1[:src-if2...] -D dst-if1[:dst-if2...]
DESCRIPTION
The ifdepd daemon implements dependencies between network interfaces in a
reliable way. If any of the source interfaces src-if1 ... src-ifn fails
(hardware error, no carrier etc.), ifdepd sets all destination interfaces
dst-if1 ... dst-ifn to state down. If all source interfaces src-if1 ...
src-ifn are active, ifdepd sets all destination interfaces dst-if1 ...
dst-ifn to state up. For example, it can be used with carp(4) to provide
failover functionality on gateways/firewalls.
The following options are available:
-v Verbose mode. The details of interface state transitions are dis‐
played on the user's terminal or in syslog messages if running in
daemon mode.
-q Quiet mode. No messages are displayed.
-d Daemon mode. Run in background and log to syslog.
-S src-if1[:src-if2...]
Specify source interface(s).
-D dst-if1[:dst-if2...]
Specify destination interface(s).
EXAMPLES
ifdepd -d -S em0:bge0 -D carp0:carp1
Example for building a high available firewall system with carp(4). The
internal physical interface is em0 and the external physical interface is
bge0, carp0 is the carp(4) interface for the internal physical interface
em0 and carp1 is the carp(4) interface for the external physical inter‐
face bge0. If one of the physical interfaces em0 or bge0 fails, ifdepd
sets both carp(4) interfaces carp0 and carp1 to down, which triggers a
failover on the carp(4) layer.
SEE ALSOcarp(4), pf(4), ifstated(8)HISTORY
The ifdepd program was written as an simple and reliable alternative for
ifstated(8) to implement interface dependencies on redundant gate‐
way/firewall systems which are using carp(4)AUTHORS
"Alexander Hausner" ⟨alex@hugo.bmg.gv.at⟩
BSD February 14, 2005 BSD