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DGortze380
February 23rd, 2010, 07:44 AM
Hi All,

I've got a really odd DHCP issue, hope someone has some insight.

I've got a Cisco 2610 router. It was previously configured as a DHCP client using the following procedure:

(config int)$ ip add dhcp client-id eth0/0 hostname 00.00.00.00.00.00

That's it. That's all it took. Worked correctly.

Now I have the same router in a different location, trying to pull an IP via DHCP from a different DHCP server. I doesn't get an address.

I've verified that it is sending BOOTP/DHCP requests. It's not getting any reply from the DHCP Server.

I tried a different network with a different DHCP Server. Same problem.

Tried connecting a computer to each of the 2 DHCP servers mentioned above. Computer gets an IP Address no problem. I've verified that it sends BOOTP/DHCP Request and receives a BOOTP/DHCP reply.

It's not a cabling issue. One NIC is auto-sensing. Besides that, I tried both a straight through and cross-over cable.

I'm a loss. I don't understand why 2 of 3 DHCP Servers don't send a reply to this router.

koszta
February 23rd, 2010, 06:38 PM
Is the other DHCP also cisco or is it Linux? I would surely try to look at wireshark sniffer to see ALL the traffic. As for my cisco experience -I would try to re-up the intfces(sh & no sh) and surely would see "show run" command. Also see if there is a startup config...
And just a question if you assign the ip manually does it work? I honestly didnt deal with very old IOSes much. I dont think that your router has any L2 security capabilities (if so make sure that some of those isnt causing the problems)
hope i helped at least some, just try posting more info if you dont get it working

DGortze380
February 23rd, 2010, 06:53 PM
Is the other DHCP also cisco or is it Linux? I would surely try to look at wireshark sniffer to see ALL the traffic. As for my cisco experience -I would try to re-up the intfces(sh & no sh) and surely would see "show run" command. Also see if there is a startup config...
And just a question if you assign the ip manually does it work? I honestly didnt deal with very old IOSes much. I dont think that your router has any L2 security capabilities (if so make sure that some of those isnt causing the problems)
hope i helped at least some, just try posting more info if you dont get it working

I don't have access to one of the other DHCP Servers. One is just my OS X laptop set up to act as a DHCP Server (for testing only).

I'll take a look at the rest of the traffic, but I'm not sure that would shed any more light on the issue.

I've tried re-up the interface, no change.

I've clear the config to eliminate any other issues. No ACLs in place, nothing, just the dhcp directive and no shutdown on one interface.

No L2 security to the best of my knowledge. It's a 2610 running 12.3

Everything works just great with manually assigned addresses. Helpful for troubleshooting, but unfortunately I need to receive a DHCP address on the WAN side of this router.

DGortze380
February 23rd, 2010, 08:31 PM
#sh ver


Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600-I-M), Version 12.3(17b), RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2006 by cisco Systems, Inc.
Compiled Mon 06-Mar-06 22:02 by dchih
Image text-base: 0x80008098, data-base: 0x80CE0844

ROM: System Bootstrap, Version 11.3(2)XA4, RELEASE SOFTWARE (fc1)
ROM: C2600 Software (C2600-I-M), Version 12.3(17b), RELEASE SOFTWARE (fc2)

Router uptime is 5 minutes
System returned to ROM by power-on
System image file is "flash:c2600-i-mz.123-17b.bin"

cisco 2610 (MPC860) processor (revision 0x203) with 28672K/4096K bytes of memor.
Processor board ID JAD05350F5Y (3879103548)
M860 processor: part number 0, mask 49
Bridging software.
X.25 software, Version 3.0.0.
2 Ethernet/IEEE 802.3 interface(s)
1 Serial network interface(s)
32K bytes of non-volatile configuration memory.
8192K bytes of processor board System flash (Read/Write)

Configuration register is 0x2102


#sh run


Building configuration...

Current configuration : 496 bytes
!
version 12.3
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname Router
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
ip subnet-zero
ip cef
!
!
!
!
!
!
!
interface Ethernet0/0
ip address dhcp
half-duplex
!
interface Serial0/0
no ip address
shutdown
no fair-queue
!
interface Ethernet1/0
no ip address
shutdown
half-duplex
!
ip http server
ip classless
!
!
!
line con 0
line aux 0
line vty 0 4
login
!
!
end


#sh int


Ethernet0/0 is up, line protocol is up
Hardware is AmdP2, address is 0007.50a4.c900 (bia 0007.50a4.c900)
Internet address will be negotiated using DHCP
MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:31, output 00:00:09, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
236 packets input, 15216 bytes, 0 no buffer
Received 221 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 input packets with dribble condition detected
74 packets output, 22755 bytes, 0 underruns
9 output errors, 0 collisions, 1 interface resets
0 babbles, 0 late collision, 0 deferred
9 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
Serial0/0 is administratively down, line protocol is down
Hardware is PQUICC with Fractional T1 CSU/DSU
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation HDLC, loopback not set
Keepalive set (10 sec)
Last input never, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
DCD=down DSR=up DTR=down RTS=down CTS=down

Ethernet1/0 is administratively down, line protocol is down
Hardware is AmdP2, address is 0007.50a4.c910 (bia 0007.50a4.c910)
MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out


#sh dhcp lease


Temp IP addr: 0.0.0.0 for peer on Interface: Ethernet0/0
Temp sub net mask: 0.0.0.0
DHCP Lease server: 0.0.0.0, state: 8 Purging
DHCP transaction id: 1C5E4
Lease: 0 secs, Renewal: 0 secs, Rebind: 0 secs
Next timer fires after: 00:00:06
Retry count: 0 Client-ID: cisco-0007.50a4.c900-Et0/0
Hostname: Router


#sh ip route
(Gateway of last resort is set to DHCP. No DHCP lease received so it shows up as not set)


Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

koszta
February 24th, 2010, 03:34 PM
From my point of view everything seems to be fine...

I found a couple liks that might be useful (I guess you read or tried them anyway already tho)

http://www.cisco.com/en/US/docs/ios/12_2t/12_2t8/feature/guide/ftwandhp.html

http://www.dslreports.com/faq/10953

This is from CISCO user guide and it seemed like a clear and good advice:
(the full thing is here http://docs.google.com/viewer?url=http://www.ciscosystems.com/en/US/docs/ios/ipaddr/configuration/guide/iad_dhcp_client.pdf )

You must configure the ip dhcp client commands before entering the ip address dhcp command on an
interface to ensure that the DHCPDISCOVER messages that are generated contain the correct option
values. The ip dhcp client commands are checked only when an IP address is acquired from DHCP. If
any of the ip dhcp client commands are entered after an IP address has been acquired from DHCP, it
will not take effect until the next time the router acquires an IP address from DHCP. This means that the
new configuration will only take effect after either the ip address dhcp command or the release dhcp
and renew dhcp EXEC commands have been configured.
1.
enable
2.
configure terminal
3.
interface type number
4.
ip dhcp client client-id {interface-name | ascii string | hex string}
5.
ip dhcp client class-id {string | hex string}
6.
ip dhcp client lease days [hours] [minutes]
7.
ip dhcp client hostname host-name
8.
[no] ip dhcp client request option-name
9.
ip address dhcp


I dont know, that is like all I can think of for now... Try the cisco guide. Hope it works at least some

DGortze380
February 24th, 2010, 07:04 PM
Unfortunately, I have seen all of those links, poured over them for 2 days now. No change.

Wireshark reveals just as I suspected.

- DHCP Server receives DHCPDISCOVER
- No reply
- Repeat

DGortze380
February 26th, 2010, 10:55 PM
Ok. I tried the configuration on another network. It works.

Brought it back and tried again. I overlooked another issue. I have a solid Activity light, but no collision warnings. Tried a cross-over cable, no change. Any ideas?