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R1(f0/0)--(f0/0)R2

R1 is dhcp server

R2 f0/0

-if)ip address dchp

R1 ---R2  should be eigrp neighbor

before R2 get the ip address for F0/0 from R1 ,R2 dont konw which "x.x.x.x" to "network " in eigrp.

except using "network 0.0.0.0 0.0.0.0 ",what else can be done to do this ?

There is a method of using EEM (action regexp) to implement this,but is there any other simple methods for these ?

I ever tried to use secondary IP address to "activate the interface for eigrp",but

R23(config-if)#ip add 200.200.200.200 255.255.255.0 sec
Secondary addresses not allowed with DHCP addresses

It seems secondary IP address cant be used with ip address dhcp

#################

This works :

R24#sh run int f0/0

ip address 23.23.23.23 255.255.255.0 secondary
ip address 24.0.0.2 255.255.255.0

router eigrp 2345
 passive-interface Loopback0
 network 23.23.23.23 0.0.0.0
 no auto-summary
 eigrp router-id 4.4.4.4

R24#sh ip eigrp nei | inc Fa0/0
2   24.0.0.1                Fa0/0             13 00:03:48  854  5000  0  87
R24#

R23#sh run int f0/0

interface FastEthernet0/0
 ip address 23.23.23.23 255.255.255.0 secondary
 ip address 24.0.0.1 255.255.255.0

router eigrp 2345
 network 23.23.23.23 0.0.0.0
 no auto-summary
 eigrp router-id 3.3.3.3

R23#sh ip eigrp nei | inc Fa0/0
2   24.0.0.2                Fa0/0             10 00:04:27   99   594  0  97
R23#

but secondary IP address cant be used with IP address dhcp.------------How to solve this?

#################

So you can't use the DHCP subnet in your network statement?

for example if your DHCP pool assigns IPs from 10.0.0.0/24, you couldn't do network 10.0.0.0 0.0.0.255?

If not, you could always do the network 0.0.0.0 0.0.0.0 with passive-interface default and then no passive-interface just the interfaces you want EIGRP on.

If the dhcp server first assigns "10.0.0.0/24",the next day the server assigns
"11.0.0.0/24",I just dont wanna to "netwrok 11.0.0.0 0.0.0.255" again on the
client router .

Btw : i have not privilege to access into the Dhcp server, I dont know which subnet it will assign to me before it assigns "IP address" to me.

Hmm, I've never seen that before. Your router interface will pull an IP address on a completely different subnet? I'm guessing then its not a direct layer 3 connection to the upstream router...

Anywho, ya I dunno, the only options I can think of are EEM (would have to think through how to perform cleanup) or an all zeros network statement with passive-interface default, or use a different IGP that you can enable on the interface.

I'd probably just leverage passive-interface. gl

this is just a trick my friend plays with me . So you must obey his rules . If in actual enviroment,change IGP to ospf is a easy solution.

THanks all the same.

Just for fun ,"network 0.0.0.0 0.0.0.0" and "passive-interface " can finish it :)

IOS 12.4(22):c7200-adventerprisek9-mz.124-22.T.bin


R1:
interface FastEthernet0/0
 ip address dhcp



event manager applet regexp
 event syslog pattern "%DHCP-6-ADDRESS_ASSIGN: Interface FastEthernet0/0"
 action 1.0 cli command "sh ip int f0/0 | inc Internet address is"
 action 1.1 set result "none"
 action 1.2 regexp "[0-9.]+" "$_cli_result" result
 action 1.3 puts "F0/0 DHCP IP address=*$result*"
 action 1.4 cli command "enable"
 action 1.5 cli command "conf t"
 action 1.6 cli command "router eigrp 100"
 action 1.7 cli command "eigrp router-id $result"
 action 1.8 cli command "network $result 0.0.0.0"
 action 1.9 cli command "end"
 action 2.0 cli command "sh run | sec eigrp"
 action 2.1 puts "$_cli_result"


R2:
ip dhcp pool X
   network 150.0.0.0 255.255.255.0
   default-router 150.0.0.254

interface FastEthernet0/0
 ip address 150.0.0.254 255.255.255.0

router eigrp 12
 network 0.0.0.0 0.0.0.0
 no auto-summary
 eigrp router-id 2.2.2.2





R1#
*Jan 29 02:39:10.599: %LINEPROTO-5-UPDOWN: Line protocol on Interface

FastEthern
et0/0, changed state to up
R1#
*Jan 29 02:39:12.927: %DHCP-6-ADDRESS_ASSIGN: Interface FastEthernet0/0

assigned
 DHCP address 150.0.0.1, mask 255.255.255.0, hostname R1

*Jan 29 02:39:13.047: %HA_EM-6-LOG: regexp: F0/0 DHCP IP

address=*150.0.0.1*
R1#
*Jan 29 02:39:13.275: %SYS-5-CONFIG_I: Configured from console by  on

vty0 (EEM:
regexp)
*Jan 29 02:39:14.331: %HA_EM-6-LOG: regexp:

 router eigrp 100
 network 150.0.0.1 0.0.0.0
 auto-summary
 eigrp router-id 150.0.0.1
 action 1.6 cli command "router eigrp 100"
 action 1.7 cli command "eigrp router-id $result"
 action 2.0 cli command "sh run | sec eigrp"
R1#
R1#