Solved: Client-identifier / Hardware Address PROBLEM

Didier1966 · ‎12-04-2010

Hello,

On my 1841 router I have some FIX IP for static devices , but one of them does not want to receive a IP that I give him.

The product always take one of the DHCP server and also work with this , but the IP that I give is never taken.

Here bellow some part of the script :

The MAC and PRINTER are working fine but MLGW , always take one from the DHCP server.

I have try to connect a CISCO 610N and WRT54GL , both of them can gove the right IP to the MLGW , I do not know what I do wrong.

I have try HARDWARE ADDRESS IEEE802 and CLIENT-IDENTIFIER , but non of them work.

ip dhcp pool MAC

host 192.168.10.50 255.255.255.0

client-identifier 0100.2312.1c0a.39

!

ip dhcp pool PRINTER

host 192.168.10.20 255.255.255.0

client-identifier 0100.242b.4d0c.5a

!

ip dhcp pool MLGW

host 192.168.10.10 255.255.255.0

client-identifier 0100.04f3.0158.b3

I have also tried to remove the 01 in front of the MAC , like you see here in the list bellow , but no difference.

ROUTER1841#sh ip dhcp bind

Bindings from all pools not associated with VRF:

IP address Client-ID/ Lease expiration Type

Hardware address/

User name

192.168.10.6 0004.f301.58b3 Dec 04 2010 11:47 AM Automatic

192.168.10.10 0100.04f3.0158.b3 Infinite Manual

192.168.10.20 0100.242b.4d0c.5a Infinite Manual

192.168.10.50 0100.2312.1c0a.39 Infinite Manual

192.168.100.20 0100.2241.353f.5e Infinite Manual

192.168.100.66 0100.089b.ad17.8f Infinite Manual

!

Any Help is welcome

I have give this server a FIX IP now , so it still work , but not the way I want it

Best Regards,

Didier

cadet alain · ‎12-04-2010

Hi,

if you put the address in the excluded addresses and in a manual binding scope your server won't get no ip address.

I just wanted to know which problem you had because it was not very clear.

Regards.

Don't forget to rate helpful posts.

View solution in original post

ksaleemjaffer · ‎12-04-2010

Hi

Also try these two basic points.

1.Clear arp cache from DHCP Router.

2.Unplug and Replug the network cable on end device. some times the end device will not clear its cache properly.

Thanks

View solution in original post

margalla · ‎12-04-2010

ROUTER1841#sh ip dhcp bind

Bindings from all pools not associated with VRF:

IP address Client-ID/ Lease expiration Type

Hardware address/

User name

192.168.10.6 0004.f301.58b3 Dec 04 2010 11:47 AM Automatic

This looks like the client is not sending a client-id so the address is being assigned based on the hw-address. You haven't shown the configuration you used for the hw-address so we can't say why that may not have worked.

Perhaps try 0004.f301.58b3 as the hw-address in your MLGW pool and show the results if it is still bad.

Also you might want to sniff the DHCP packets so we can see exactly what the client is asking.

If you don't have a sniffer, you could possibly try one of these IOS tools:

Router IP Traffic Export Packet Capture Enhancements

http://www.cisco.com/en/US/docs/ios/12_4t/12_4t11/ht_rawip.html

Embedded Packet Capture

http://tools.cisco.com/squish/5C213

View solution in original post

cadet alain · ‎12-05-2010

Hi,

Try this:

ip dhcp pool MLGW

host 192.168.10.10 255.255.255.0

hardware-address 0004.f301.58b3

Regards.

Don't forget to rate helpful posts.

View solution in original post

margalla · ‎12-05-2010

PS : WHY DO SOME COMPUTERS NEED "Client-identifier" and others "Hardware-address" ?

Dynamic Host Configuration Protocol

http://www.ietf.org/rfc/rfc2131.txt

"DHCP defines a new 'client identifier' option that is used to pass an

explicit client identifier to a DHCP server. This change eliminates

the overloading of the 'chaddr' field in BOOTP messages, where

'chaddr' is used both as a hardware address for transmission of BOOTP

reply messages and as a client identifier. The 'client identifier'

is an opaque key, not to be interpreted by the server; for example,

the 'client identifier' may contain a hardware address, identical to

the contents of the 'chaddr' field, or it may contain another type of

identifier, such as a DNS name. The 'client identifier' chosen by a

DHCP client MUST be unique to that client within the subnet to which

the client is attached. If the client uses a 'client identifier' in

one message, it MUST use that same identifier in all subsequent

messages, to ensure that all servers correctly identify the client."

So the client chooses to send a client-identifier or not. If it does the server has to use it. If it doesn't the server looks at hw-address instead.

View solution in original post

cadet alain · ‎12-04-2010

Hi,

you wang a static ip for this device, not a manual binding like you did so you must be sure to configure this server with this static ip and exclude it from the scope in your dhcp server.

Is this your problem?

Don't forget to rate helpful posts.

Didier1966 · ‎12-04-2010

Hello,

I hope I understand you correctly , I have removed the IP ADDRESS that I have put in the MLGW FIX POOL , but it is still the same

no ip dhcp use vrf connected

ip dhcp excluded-address 192.168.10.1

ip dhcp excluded-address 192.168.20.1

ip dhcp excluded-address 192.168.30.1

ip dhcp excluded-address 192.168.100.1

ip dhcp excluded-address 192.168.1.250 192.168.1.254

ip dhcp excluded-address 192.168.10.10

!

ip dhcp pool vlan10

import all

network 192.168.10.0 255.255.255.0

default-router 192.168.10.1

dns-server 8.8.8.8

lease 5

!

ip dhcp pool vlan20

import all

network 192.168.20.0 255.255.255.0

dns-server 8.8.8.8

default-router 192.168.20.1

lease 5

!

ip dhcp pool vlan30

import all

network 192.168.30.0 255.255.255.0

dns-server 8.8.8.8

default-router 192.168.30.1

!

ip dhcp pool FIX-IP

host 192.168.100.66 255.255.255.0

client-identifier 0100.089b.ad17.8f

client-name FIX-IP

!

ip dhcp pool TEST

host 192.168.100.20 255.255.255.0

client-identifier 0100.2241.353f.5e

!

ip dhcp pool internal

network 192.168.100.0 255.255.255.0

dns-server 192.168.100.1

default-router 192.168.100.1

!

ip dhcp pool vlan1

network 192.168.1.0 255.255.255.0

dns-server 8.8.8.8

default-router 192.168.1.1

lease 5

!

ip dhcp pool MAC

host 192.168.10.50 255.255.255.0

client-identifier 0100.2312.1c0a.39

!

ip dhcp pool PRINTER

host 192.168.10.20 255.255.255.0

client-identifier 0100.242b.4d0c.5a

!

ip dhcp pool MLGW

host 192.168.10.10 255.255.255.0

client-identifier 0100.04f3.0158.b3

default-router 192.168.10.1

!

cadet alain · ‎12-04-2010

Hi,

if you put the address in the excluded addresses and in a manual binding scope your server won't get no ip address.

I just wanted to know which problem you had because it was not very clear.

Regards.

Don't forget to rate helpful posts.

Didier1966 · ‎12-04-2010

Hello Cadetalain,

What I would like to archive is to send all FIX IP from the CISCO ROUTER to :

PRINTERS

NAS DRIVE

CAM

WEB SERVER (MLGW) RUNNING UNDER LINUX

All of the above have the ability to have a FIX IP , but I prefer to do it from the ROUTER.

All of them work even my MAC and PC's here in the home , the ONLY one that give me troubles is the WEB SERVER.

He receive always a IP from the FIRST DHCP POOL VLAN10 and NOT from the DHCP POOL MLGW , like you can see here bellow.

I have tried the MAC ADDRESS WITH and WITHOUT the 01 in front of the MAC ADDRESS , without success.

ip dhcp excluded-address 192.168.10.1

ip dhcp excluded-address 192.168.20.1

ip dhcp excluded-address 192.168.30.1

ip dhcp excluded-address 192.168.100.1

ip dhcp excluded-address 192.168.1.250 192.168.1.254

!

ip dhcp pool vlan10

import all

network 192.168.10.0 255.255.255.0

default-router 192.168.10.1

dns-server 8.8.8.8

lease 5

!

ip dhcp pool vlan20

import all

network 192.168.20.0 255.255.255.0

dns-server 8.8.8.8

default-router 192.168.20.1

lease 5

ip dhcp pool MAC

host 192.168.10.50 255.255.255.0

client-identifier 0100.2312.1c0a.39

!

ip dhcp pool PRINTER

host 192.168.10.20 255.255.255.0

client-identifier 0100.242b.4d0c.5a

!

ip dhcp pool MLGW

host 192.168.10.10 255.255.255.0

client-identifier 0004.f301.58b3

!

Best Regards,

Didier

ksaleemjaffer · ‎12-04-2010

Hi

Also try these two basic points.

1.Clear arp cache from DHCP Router.

2.Unplug and Replug the network cable on end device. some times the end device will not clear its cache properly.

Thanks

Didier1966 · ‎12-04-2010

Hello,

I have try all the above without success

Do not loose too much time on my case , you have other priorities

I just like to know why on some COMPUTERS or SERVERS or NAS drivers it works , and why it does not work on others.

I have put some DEBUG ON , to see what is going on , but I can see that DHCPOFFER send 192.168.10.3 instead of 192.168.10.10

Here bellow the result :

ROUTER1841#sh debug

Generic IP:

IP Address activity debugging is on

DHCP server packet debugging is on.

DHCP server redundancy debugging is on.

NETBIOS:

NetBIOS packet display debugging is on

DHCPC:

DHCP client activity debugging is on

Condition 1: vlan 10 (1 flags triggered)

Flags: 10

Condition 2: ip 192.168.10.10 (0 flags triggered)

ROUTER1841#

*Dec 4 22:35:04.159: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0/0, changed state to down

*Dec 4 22:35:05.159: %LINK-3-UPDOWN: Interface FastEthernet0/0/0, changed state to down

*Dec 4 22:35:08.114: %LINK-3-UPDOWN: Interface FastEthernet0/0/0, changed state to up

*Dec 4 22:35:09.114: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0/0, changed state to up

*Dec 4 22:35:22.253: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0/0, changed state to down

*Dec 4 22:35:23.257: %LINK-3-UPDOWN: Interface FastEthernet0/0/0, changed state to up

*Dec 4 22:35:24.257: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0/0, changed state to up

*Dec 4 22:35:30.684: DHCPD: DHCPDISCOVER received from client 0004.f301.58b3 on interface Vlan10.

*Dec 4 22:35:30.684: DHCPD: Sending DHCPOFFER to client 0004.f301.58b3 (192.168.10.3).

*Dec 4 22:35:30.684: DHCPD: creating ARP entry (192.168.10.3, 0004.f301.58b3, vrf 0).

*Dec 4 22:35:30.684: DHCPD: unicasting BOOTREPLY to client 0004.f301.58b3 (192.168.10.3).

*Dec 4 22:35:30.744: DHCPD: DHCPREQUEST received from client 0004.f301.58b3.

*Dec 4 22:35:30.744: DHCPD: Appending default domain from pool

*Dec 4 22:35:30.744: DHCPD: Using hostname 'mlgw.telenet.be.' for dynamic update (from hostname option)

*Dec 4 22:35:30.744: DHCPD: Sending DHCPACK to client 0004.f301.58b3 (192.168.10.3).

*Dec 4 22:35:30.744: DHCPD: creating ARP entry (192.168.10.3, 0004.f301.58b3, vrf 0).

*Dec 4 22:35:30.748: DHCPD: unicasting BOOTREPLY to client 0004.f301.58b3 (192.168.10.3).

margalla · ‎12-04-2010

ROUTER1841#sh ip dhcp bind

Bindings from all pools not associated with VRF:

IP address Client-ID/ Lease expiration Type

Hardware address/

User name

192.168.10.6 0004.f301.58b3 Dec 04 2010 11:47 AM Automatic

This looks like the client is not sending a client-id so the address is being assigned based on the hw-address. You haven't shown the configuration you used for the hw-address so we can't say why that may not have worked.

Perhaps try 0004.f301.58b3 as the hw-address in your MLGW pool and show the results if it is still bad.

Also you might want to sniff the DHCP packets so we can see exactly what the client is asking.

If you don't have a sniffer, you could possibly try one of these IOS tools:

Router IP Traffic Export Packet Capture Enhancements

http://www.cisco.com/en/US/docs/ios/12_4t/12_4t11/ht_rawip.html

Embedded Packet Capture

http://tools.cisco.com/squish/5C213

Didier1966 · ‎12-04-2010

Hello Margalla,

Thank you also for this useful information , here bellow I have put the FULL config :

version 12.4

service timestamps debug datetime msec

service timestamps log datetime msec

service password-encryption

!

hostname ROUTER1841

!

boot-start-marker

boot-end-marker

!

logging buffered 51200 warnings

enable password 7 05080F1C2243

!

aaa new-model

!

aaa authentication banner

THIS SYSTEM IS SOLELY FOR USE OF AUTHORISED USERS FOR OFFICIAL PURPOSES

!

aaa session-id common

clock timezone gmt+1 1

clock summer-time gmt+2 recurring last Sun Mar 2:00 last Sun Oct 3:00

dot11 syslog

no ip source-route

ip cef

!

no ip dhcp use vrf connected

ip dhcp excluded-address 192.168.10.1

ip dhcp excluded-address 192.168.20.1

ip dhcp excluded-address 192.168.30.1

ip dhcp excluded-address 192.168.100.1

ip dhcp excluded-address 192.168.1.250 192.168.1.254

!

ip dhcp pool vlan10

import all

network 192.168.10.0 255.255.255.0

default-router 192.168.10.1

dns-server 8.8.8.8

lease 5

!

ip dhcp pool vlan20

import all

network 192.168.20.0 255.255.255.0

dns-server 8.8.8.8

default-router 192.168.20.1

lease 5

!

ip dhcp pool vlan30

import all

network 192.168.30.0 255.255.255.0

dns-server 8.8.8.8

default-router 192.168.30.1

!

ip dhcp pool FIX-IP

host 192.168.100.66 255.255.255.0

client-identifier 0100.089b.ad17.8f

client-name FIX-IP

!

ip dhcp pool TEST

host 192.168.100.20 255.255.255.0

client-identifier 0100.2241.353f.5e

!

ip dhcp pool internal

network 192.168.100.0 255.255.255.0

dns-server 192.168.100.1

default-router 192.168.100.1

!

ip dhcp pool vlan1

network 192.168.1.0 255.255.255.0

dns-server 8.8.8.8

default-router 192.168.1.1

lease 5

!

ip dhcp pool MAC

host 192.168.10.50 255.255.255.0

client-identifier 0100.2312.1c0a.39

!

ip dhcp pool PRINTER

host 192.168.10.20 255.255.255.0

client-identifier 0100.242b.4d0c.5a

!

ip dhcp pool MLGW

host 192.168.10.10 255.255.255.0

client-identifier 0004.f301.58b3

!

no ip bootp server

ip domain name dri

ip host SW12 192.168.1.252

ip host SW24 192.168.1.251

ip ddns update method DynDNS

HTTP

add http://dri66@members.dyndns.org/nic/update?system=dyndns&hostname=mlgw.dyndns.info&myip=//dri66@members.dyndns.org/nic/update?system=dyndns&hostname=mlgw.dyndns.info&myip=

interval maximum 1 0 0 0

interval minimum 1 0 0 0

!

multilink bundle-name authenticated

!

crypto pki trustpoint TP-self-signed-2996752687

enrollment selfsigned

subject-name cn=IOS-Self-Signed-Certificate-2996752687

revocation-check none

rsakeypair TP-self-signed-2996752687

!

username Admin privilege 15 secret 5 $1$gAFQ$6WYuTY9G/

archive

log config

hidekeys

!

ip ssh time-out 60

ip ssh authentication-retries 2

ip ssh port 8096 rotary 1

ip ssh version 2

!

interface FastEthernet0/0

description DMZ

ip ddns update hostname mlgw.dyndns.info

ip ddns update DynDNS

ip address dhcp

no ip unreachables

no ip proxy-arp

ip nat outside

ip virtual-reassembly

duplex auto

speed auto

!

interface FastEthernet0/1

description INTERNAL$ETH-LAN$

ip address 192.168.100.1 255.255.255.0

no ip proxy-arp

ip nat inside

ip virtual-reassembly

duplex auto

speed auto

!

interface FastEthernet0/0/0

switchport access vlan 10

spanning-tree portfast

!

interface FastEthernet0/0/1

switchport access vlan 20

spanning-tree portfast

!

interface FastEthernet0/0/2

switchport access vlan 30

spanning-tree portfast

!

interface FastEthernet0/0/3

switchport mode trunk

!

interface Vlan1

ip address 192.168.1.250 255.255.255.0

ip nat inside

ip virtual-reassembly

!

interface Vlan10

ip address 192.168.10.1 255.255.255.0

ip nat inside

ip virtual-reassembly

!

interface Vlan20

ip address 192.168.20.1 255.255.255.0

ip nat inside

ip virtual-reassembly

!

interface Vlan30

ip address 192.168.30.1 255.255.255.0

ip nat inside

ip virtual-reassembly

!

ip forward-protocol nd

!

no ip http server

ip http authentication local

ip http secure-server

ip dns server

ip nat inside source list 101 interface FastEthernet0/0 overload

ip nat inside source static tcp 192.168.10.10 80 interface FastEthernet0/0 8095

!

access-list 101 permit ip 192.168.10.0 0.0.0.255 any

access-list 101 permit ip 192.168.20.0 0.0.0.255 any

access-list 101 permit ip 192.168.30.0 0.0.0.255 any

access-list 101 permit ip 192.168.100.0 0.0.0.255 any

access-list 101 permit ip 192.168.1.0 0.0.0.255 any

no cdp run

!

control-plane

!

banner exec

WELCOME YOU ARE NOW LOGED IN

banner login

WARNING !!!

IF YOU ARE NOT :

Didier Ribbens

Please Leave NOW !!!

YOUR IP and MAC address will be LOGGED !!!

!

line con 0

speed 115200

line aux 0

line vty 0 4

access-class 5 in

privilege level 15

rotary 1

transport input telnet ssh

line vty 5 15

access-class 5 in

rotary 1

!

scheduler allocate 20000 1000

ntp clock-period 17178443

ntp server 66.27.60.10

end

Best Regrds,

Didier

cadet alain · ‎12-05-2010

Hi,

Try this:

ip dhcp pool MLGW

host 192.168.10.10 255.255.255.0

hardware-address 0004.f301.58b3

Regards.

Don't forget to rate helpful posts.

Didier1966 · ‎12-05-2010

Hello,

I did a compilation of all the information :

REMOVED THE CABLE

CLEAR THE ARP-CACHE

CLERA THE IP DHCP BINDINGS

And what you told me to do :

p dhcp pool MLGW

host 192.168.10.10 255.255.255.0

hardware-address 0004.f301.58b3

and IT WORKS.

Thank You ALL

PS : WHY DO SOME COMPUTERS NEED "Client-identifier" and others "Hardware-address" ?

Best Regards,

Didier

margalla · ‎12-05-2010

PS : WHY DO SOME COMPUTERS NEED "Client-identifier" and others "Hardware-address" ?

Dynamic Host Configuration Protocol