On 5 Mar 2009, at 10:24, Peter Rathlev wrote:
On Wed, 2009-03-04 at 13:00 +0000, Michael Robson wrote:
I have recently moved the routing of a subnet from an old sup2/msfc2
6500 (Version 12.1(26)E8, RELEASE SOFTWARE (fc1)) to a newer sup3/
msfc3 6500 (Version 12.2(18)SXF13, RELEASE SOFTWARE (fc1)). On the
old
router the udp-helper command worked fine, but on the new router I
can
see the DHCP address coming in but not the reply coming back and the
DHCP server isn't seeing the request arriving. Can anyone suggest why
this might have stopped working (it isn't an ACL or firewall issue as
there aren't any in the way) and I haven't turned _off_ any component
of udp-helper (i.e. using the ip forward-protocol command).
interface Vlan937
description XXXYYYZZZ
ip address w.x.y.z 255.255.255.192
ip helper-address a.b.c.d
AFAIK this forwarding requires the device to have "service dhcp",
which
is default. Do you have "no service dhcp" defined maybe?
(I might have misunderstood this requirement though.)
The DHCP is no on a router, but a linux server several hops away.
We use this in many places for Sup720 SXF13 boxes, so it should work.
Another thing could be the DHCP server. If you know "by sniff" that
the
packet doesn't arrive at the DHCP this is not relevant, but the DHCP
server would of course only reply if e.g. netmasks are the same.
The traffic doesn't arrive at the DHCP server.
Thanks,
Michael
--
_______________________________________________
cisco-nsp mailing list [email protected]
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/
