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ISR Vlan Interface IP Address assigned by DHCP (Client)

judu
Level 1
Level 1

I am using a Cisco C1111 ISR w/ 2 L3 interfaces, 8 L2 interfaces. 

Interface Vlan601 currently has an IP address assigned to it. I would like to use DHCP to assign the IP address to this interface. However, when I change it to DHCP, the MAC address in the DHCP request is 0000.0000.0000 which is causing the DHCP request to fail. 

Starting Point:

Interface              IP-Address      OK? Method Status                Protocol
GigabitEthernet0/1/0   unassigned      YES unset  up                    up      
Vlan601                192.168.1.50    YES NVRAM  up                    up     
interface GigabitEthernet0/1/0
 switchport access vlan 601
 switchport mode access

interface Vlan601
 description PartnerNet1
 ip vrf forwarding PARTNER-NET-1
 ip address 192.168.1.50 255.255.255.0
 ip nat outside
router#ping vrf PARTNER-NET-1 192.168.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.1, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 1/1/4 ms
router#show int Gi0/1/0
GigabitEthernet0/1/0 is up, line protocol is up (connected) 
  Hardware is C1111-ES-8, address is 5c64.f184.b088 (bia 5c64.f184.b088)
  MTU 1500 bytes, BW 100000 Kbit/sec, DLY 100 usec, 
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  Keepalive not supported 
  Full-duplex, 100Mb/s, link type is auto, media type is 10/100/1000BaseTX
  input flow-control is off, output flow-control is unsupported 
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:36, output 00:00:13, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/375/0/0 (size/max/drops/flushes); Total output drops: 0
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  5 minute input rate 1000 bits/sec, 2 packets/sec
  5 minute output rate 1000 bits/sec, 2 packets/sec
     950 packets input, 76619 bytes, 0 no buffer
     Received 24 broadcasts (11 multicasts)
     0 runts, 0 giants, 0 throttles 
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 11 multicast, 0 pause input
     0 input packets with dribble condition detected
     933 packets output, 79668 bytes, 0 underruns
     Output 2 broadcasts (18 multicasts)
     0 output errors, 0 collisions, 1 interface resets
     0 unknown protocol drops
     0 babbles, 0 late collision, 0 deferred
     0 lost carrier, 0 no carrier, 0 pause output
     0 output buffer failures, 0 output buffers swapped out
router#show ip int Vlan601
Vlan601 is up, line protocol is up
  Internet address is 192.168.1.50/24
  Broadcast address is 255.255.255.255
  Address determined by non-volatile memory
  MTU is 1500 bytes
  Helper address is not set
  Directed broadcast forwarding is disabled
  Outgoing Common access list is not set 
  Outgoing access list is not set
  Inbound Common access list is not set 
  Inbound  access list is not set
  Proxy ARP is enabled
  Local Proxy ARP is disabled
  Security level is default
  Split horizon is enabled
  ICMP redirects are always sent
  ICMP unreachables are always sent
  ICMP mask replies are never sent
  IP fast switching is enabled
  IP Flow switching is disabled
  IP CEF switching is enabled
  IP CEF switching turbo vector
  IP Null turbo vector
  VPN Routing/Forwarding "PARTNER-NET-1"
  Associated unicast routing topologies:
        Topology "base", operation state is UP
  IP multicast fast switching is enabled
  IP multicast distributed fast switching is disabled
  IP route-cache flags are Fast, CEF
  Router Discovery is disabled
  IP output packet accounting is disabled
  IP access violation accounting is disabled
  TCP/IP header compression is disabled
  RTP/IP header compression is disabled
  Probe proxy name replies are disabled
  Policy routing is disabled
  Network address translation is enabled, interface in domain outside
  BGP Policy Mapping is disabled
  Input features: Virtual Fragment Reassembly, NAT Outside, MCI Check
  Output features: Post-routing NAT Outside
  IPv4 WCCP Redirect outbound is disabled
  IPv4 WCCP Redirect inbound is disabled
  IPv4 WCCP Redirect exclude is disabled
  IP Clear Dont Fragment is disabled

I remove the IP address from the Vlan601 interface. 

router(config)#int Vlan601
router(config-if)#no ip address
router#show ip int br
Interface              IP-Address      OK? Method Status                Protocol  
GigabitEthernet0/1/0   unassigned      YES unset  up                    up      
Vlan601                unassigned      YES manual up                    up     

I then set the IP address to DHCP. I have tried this as just "ip address dhcp" and with the client-id set to the physical interface, and with a hostname set. Showing the last iteration. There are not many options available here. 

interface Vlan601
 description PartnerNet1
 ip vrf forwarding PARTNER-NET-1
 ip address dhcp client-id GigabitEthernet0/1/0 hostname Cisco
 ip nat outside
end
router#show ip int br
Interface              IP-Address      OK? Method Status                Protocol 
GigabitEthernet0/1/0   unassigned      YES unset  up                    up      
Vlan601                unassigned      YES DHCP   up                    up      
router(config-if)#ip address dhcp ?
  client-id  Specify client-id to use
  hostname   Specify value for hostname option
  <cr>       <cr>

router(config-if)#ip address dhcp client-id ?
  BD-VIF           Bridge-Domain Virtual IP interface
  BDI              Bridge-Domain interface
  GigabitEthernet  GigabitEthernet IEEE 802.3z
  Port-channel     Ethernet Channel of interfaces
  Vlan             Catalyst Vlans

router(config-if)#ip address dhcp client-id GigabitEthernet 0/1/0 ?
  hostname  Specify value for hostname option
  <cr>      <cr>

But the ip dhcp debug shows the MAC address being set as all zeros. 

Sep  8 17:15:15.174: DHCP: Try 3 to acquire address for Vlan601
Sep  8 17:15:15.177: DHCP: allocate request
Sep  8 17:15:15.177: DHCP: zapping entry in DHC_PURGING state for Vl601
Sep  8 17:15:15.177: DHCP: deleting entry FFFF56A0D0F8 0.0.0.0 from list
Sep  8 17:15:15.177: DHCP: new entry. add to queue, interface Vlan601
Sep  8 17:15:15.177: DHCP: MAC address specified as  0000.0000.0000 (0 0). Xid is 10A945FE
Sep  8 17:15:15.177: DHCP: SDiscover attempt # 1 for entry:
Sep  8 17:15:15.178: DHCP: Scan: Option vendor class Identifier 124
Sep  8 17:15:15.178: Enterprise ID 9
Sep  8 17:15:15.178: vendor-class-data-len 13
Sep  8 17:15:15.178: data: C1111-8PLTEEA
Sep  8 17:15:15.178: DHCP: SDiscover: sending 305 byte length DHCP packet
Sep  8 17:15:15.178: DHCP: SDiscover 305 bytes 
Sep  8 17:15:15.178:             B'cast on Vlan601 interface from 0.0.0.0
Sep  8 17:15:18.200: DHCP: SDiscover attempt # 2 for entry:
Sep  8 17:15:18.200: DHCP: Scan: Option vendor class Identifier 124
Sep  8 17:15:18.200: Enterprise ID 9
Sep  8 17:15:18.200: vendor-class-data-len 13
Sep  8 17:15:18.201: data: C1111-8PLTEEA
Sep  8 17:15:18.201: DHCP: SDiscover: sending 305 byte length DHCP packet
Sep  8 17:15:18.201: DHCP: SDiscover 305 bytes 
Sep  8 17:15:18.201:             B'cast on Vlan601 interface from 0.0.0.0
Sep  8 17:15:22.202: DHCP: SDiscover attempt # 3 for entry:
Sep  8 17:15:22.202: DHCP: Scan: Option vendor class Identifier 124
Sep  8 17:15:22.202: Enterprise ID 9
Sep  8 17:15:22.202: vendor-class-data-len 13
Sep  8 17:15:22.202: data: C1111-8PLTEEA
Sep  8 17:15:22.202: DHCP: SDiscover: sending 305 byte length DHCP packet
Sep  8 17:15:22.202: DHCP: SDiscover 305 bytes 
Sep  8 17:15:22.202:             B'cast on Vlan601 interface from 0.0.0.0
%Unknown DHCP problem.. No allocation possible
Sep  8 17:15:35.657: DHCP: Waiting for 15 seconds on interface Vlan601

How can I set the MAC address to use the MAC address of the Gi0/1/0 or some other viable solution?

 

40 Replies 40

Thank you for the run config.

If you can not have 2 overlap IP address, why do you need VLAN 1 here ?

interface GigabitEthernet0/0/1
description gig 0/0/1
ip address 192.168.1.1 255.255.255.0
ip nat inside
negotiation auto
ip virtual-reassembly

interface Vlan1
ip helper-address 192.168.1.1
ip nat inside
vlan-autoconfig

You can have any one them need for that to work, or if you have need different VLAN, then use different RFC 1918 addres with out overlap.

 

BB

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How to Ask The Cisco Community for Help

I was under the impression that all of the 8 ports on the router are mapped to vlan1 by default.  Are you saying I should eliminate VLAN1?

Do you have a config that you know would work?

Hello
Can you confirm as this iis an svi  then assumption is the dhcp server reachable from that vrf and its connected physical interface?
Meaning it’s not reachable via the global route table (GRT)


Please rate and mark as an accepted solution if you have found any of the information provided useful.
This then could assist others on these forums to find a valuable answer and broadens the community’s global network.

Kind Regards
Paul

In the early stages of this discussion the config showed a DHCP pool configured on the new Cisco router. So it was local and  reachability was certainly not an issue. At that point the issue was that the subnet of the DHCP pool was assigned to physical interface G0/0/1 and therefore was not available to devices connected to vlan 1 who needed to use addresses in that subnet.

Some changes were made but the DHCP still did not work. And then the router was reset. So we are effectively starting from the beginning. When the router is recovered and is functional we can address issues about DHCP.

HTH

Rick

Well, I was able to get the file and re-load the OS.  The router is now assigning IP addresses but when I plug my MacBook in to the lan port (#5) I get connection errors trying to access the GUI  https://www.cisco.com/c/en/us/td/docs/routers/access/isr1100/software/configuration/xe-17/isr1100-sw-config-xe-17/mgmt_interfaces.html

Safari and Chrome give different responses but it seems the router is not allowing the MacBook to access 192.168.1.1.  I've checked all the settings on the browser and tried turning off the firewall (Edge with my Surface).

Not sure what the issue is

Can you verify what IP address, mask, and default gateway are assigned to your MacBook? and can you post the configuration of the port to which it connects and of the vlan interface for that port?

HTH

Rick

I won't have access to the machine until Friday and will send the running config.  First time I plugged it in it received 192.168.1.6  . I think 255.255.255.0 but would have to check again.  When I plugged in the Surface it received 192.168.1.7.  I also plugged in my switch and the light on the front went to steady which means it was assigned an IP address.

The vlan1 interface is configured as instructed in the document mentioned above

 

Cisco 1000 Series Software Configuration Guide, Cisco IOS XE 17 - Setting Up Factory Default Device Using WebUI [Cisco 1000 Series Integrated Services Routers] - Cisco

interface Vlan1 ip address 192.168.1.1 255.255.255.0

ip nat inside

no shutdown

I've been reading about the management interface  gigabitethernet0  .  Might that have something to do with this issue?

Thanks for the additional information. It may be helpful to see the running config. In the meantime  I have a couple things:

- when you connected the Surface it worked ok? Was able to access resources in the local subnet? Was able to access resources in remote subnets?

- when you were connecting the various devices it was always to the same port?

- without knowing more it is difficult to be sure but I find it hard to understand how management interface gig0 would be part of this issue.

HTH

Rick

What is the best way for me to share the configuration with you?

 I use PuTTY on a Microsoft Surface to access the CLI through the control port

I am not familiar with the capabilities of Surface, but if you are using  PuTTY can you do a show run, highlight and copy the output, and then paste it in a response in the community?

HTH

Rick

I turned the machine off for the week and when I turned it on it came up in rommon.

I just spent 2 hours with the tech from Cisco.  It turns out that IOS-XE 17.12 (which is what they gave me) needs an updated rommon.  The tech loaded 17.6 which automatically upgrades the rommon and then went to 17.12

The machine boots in 17.12 now and I executed the configuration commands to access the GUI.  I can now access the GUI login page and enter my credentials.  I get the spinning balls and then the screen goes whitte and stays there.

Any idea what might be causing it?

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