[pkg-dhcp-devel] Bug#648401: isc-dhcp-relay: dhcrelay(8) doesn't mention need for -i on server facing interface

[Geoff Crompton]

Package: isc-dhcp-relay
Version: 4.1.1-P1-15+squeeze3
Severity: normal
Tags: patch

The dhcrelay man page doesn't mention that if you use any -i option to
specify interfaces, you need to add an -i option for the interface used to
contact the DHCP server. Otherwise dhcrelay silently drops the packets
(which took me an afternoon to figure out).

It seems some versions of the dhcrelay man page have had this as a warning,
see this copy:
http://linuxcommand.org/man_pages/dhcrelay8.html
I haven't checked when the documentation changed. I've added a patch with my
suggested alteration to the man page.


-- System Information:
Debian Release: 6.0.3
  APT prefers stable
  APT policy: (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 2.6.32-5-amd64 (SMP w/8 CPU cores)
Locale: LANG=en_AU.UTF-8, LC_CTYPE=en_AU.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages isc-dhcp-relay depends on:
ii  debconf [debconf-2. 1.5.36.1             Debian configuration management sy
ii  debianutils         3.4                  Miscellaneous utilities specific t
ii  isc-dhcp-common     4.1.1-P1-15+squeeze3 common files used by all the isc-d
ii  libc6               2.11.2-10            Embedded GNU C Library: Shared lib

isc-dhcp-relay recommends no packages.

isc-dhcp-relay suggests no packages.

-- debconf information excluded
-------------- next part --------------
--- dhcrelay.8.orig	2011-11-11 16:41:22.000000000 +1100
+++ dhcrelay.8	2011-11-11 16:43:01.000000000 +1100
@@ -178,7 +178,10 @@
 interfaces may be specified by using more than one \fB-i\fR option.  If
 no interfaces are specified on the command line, dhcrelay will identify
 all network interfaces, eliminating non-broadcast interfaces if possible,
-and attempt to listen on all of them.
+and attempt to listen on all of them. If you use -i, you should ensure you
+include an -i option for the interface that is used to communicate with the
+DHCP server. Otherwise reply packets from the DHCP server are likely to be
+dropped.
 .TP
 -m \fIappend\fR|\fIreplace\fR|\fIforward\fR|\fIdiscard\fR
 Control the handling of incoming DHCPv4 packets which already contain