Re: OT- IP Helper-Address

Hello Asif,

The answer is that that the Router/Switch will send it to all at the same
time. The configurations pasted below are taken from the following link. The
debug messages tell the whole story.

https://supportforums.cisco.com/thread/160572

R3 (F0/1) <--LAN--> (F0/1) R1

 R3:

interface FastEthernet0/1

description R1

ip address 192.168.13.3 255.255.255.0

ip helper-address 192.168.34.4

ip helper-address 192.168.34.5

R1:

interface FastEthernet0/1

description R3

ip address dhcp

shutdown

duplex auto

speed auto

no clns route-cache

R1(config-if)#int f0/1

R1(config-if)#no shut

R3#

00:05:22: DHCPD: setting giaddr to 192.168.13.3.

00:05:22: DHCPD: BOOTREQUEST from
0063.6973.636f.2d63.6130.302e.3166.6338.2e30.3030.362d.4661.302f.31
forwarded to 192.168.34.4.

00:05:22: DHCPD: BOOTREQUEST from
0063.6973.636f.2d63.6130.302e.3166.6338.2e30.3030.362d.4661.302f.31
forwarded to 192.168.34.5.

00:05:23: IP-EIGRP(Default-IP-Routing-Table:1): Neighbor 0.0.0.0 not on
common subnet for FastEthernet0/1

00:05:25: DHCPD: setting giaddr to 192.168.13.3.

00:05:25: DHCPD: BOOTREQUEST from
0063.6973.636f.2d63.6130.302e.3166.6338.2e30.3030.362d.4661.302f.31
forwarded to 192.168.34.4.

00:05:25: DHCPD: BOOTREQUEST from
0063.6973.636f.2d63.6130.302e.3166.6338.2e30.3030.362d.4661.302f.31
forwarded to 192.168.34.5.

00:05:27: DHCPD: setting giaddr to 192.168.13.3.

00:05:27: DHCPD: BOOTREQUEST from
0063.6973.636f.2d63.6130.302e.3166.6338.2e30.3030.362d.4661.302f.31
forwarded to 192.168.34.4.

00:05:27: DHCPD: BOOTREQUEST from
0063.6973.636f.2d63.6130.302e.3166.6338.2e30.3030.362d.4661.302f.31
forwarded to 192.168.34.5.

HTH,

On Tue, Nov 9, 2010 at 11:45 AM, Asif Vanoo <asif_at_vanoo.net> wrote:

> Hello,
>
> My question is _*"Which IP Helper-address statement will take
> priority"*_ as per mentioned config.
> I didnt find any document related to _*IP Helper-Address Priority*_,
>
> interface FastEthernet1
> description Bldg 1 Network A
> ip address 172.69.93.1 255.255.255.192
> ip helper-address 172.69.2.74
> ip helper-address 172.69.2.123
> ip helper-address 172.69.30.31
> ip helper-address 172.69.2.121
> ip helper-address 172.71.84.140
> ip helper-address 172.69.67.35
>
> Any input with supporting cisco document will be helpful
>
> Thanks
> Asif
>
>
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-- 
KJ
Blogs and organic groups at http://www.ccie.net