09-30-2015 01:53 PM - edited 03-05-2019 02:25 AM
I KNOW there has to be a ton of examples but I'm unable to find them. The router is behind a cable modem and it gets DHCP from that. I can see the router get the DHCP but for some reason it won't route or is not subnetted properly. Maybe I've just plain screwed it up: for example, it seems like there are two DHCP addresses it gets.
__________________________________________________________________________________________________-
*Sep 30 19:24:49.783: %DHCP-6-ADDRESS_ASSIGN: Interface FastEthernet0/1 assigned DHCP address 192.168.100.10, mask 255.255.255.0, hostname hillside.lan
*Sep 30 19:25:08.895: %DHCP-6-ADDRESS_ASSIGN: Interface FastEthernet0/1 assigned DHCP address 24.165.208.144, mask 255.255.254.0, hostname hillside.lan
hillside.lan#show ip interface brief
Interface IP-Address OK? Method Status Prot ocol
FastEthernet0/0 192.168.1.1 YES NVRAM up up
FastEthernet0/1 24.165.208.144 YES DHCP up up
Serial0/0/0 unassigned YES NVRAM administratively down down
NVI0 192.168.1.1 YES unset up up
hillside.lan#show ip route
Codes: L - local, 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, H - NHRP, l - LISP
+ - replicated route, % - next hop override
Gateway of last resort is 24.165.208.1 to network 0.0.0.0
S* 0.0.0.0/0 [1/0] via 24.165.208.1
24.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 24.165.208.0/23 is directly connected, FastEthernet0/1
L 24.165.208.144/32 is directly connected, FastEthernet0/1
142.254.0.0/32 is subnetted, 1 subnets
S 142.254.151.209 [254/0] via 24.165.208.1, FastEthernet0/1
192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.1.0/24 is directly connected, FastEthernet0/0
L 192.168.1.1/32 is directly connected, FastEthernet0/0
_______________________________________________________________________________________-
Here is the config from the router:
!
version 15.1
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname hillside.lan
!
boot-start-marker
boot-end-marker
!
!
enable password XXXXXX
!
no aaa new-model
!
dot11 syslog
no ip source-route
!
!
ip cef
ip domain name hillside.lan
ip name-server 8.8.8.8
ip name-server 8.8.4.4
!
multilink bundle-name authenticated
!
!
license udi pid CISCO1841 sn XXXXXX
username XXXXX password 0 15 XXXXXX
!
redundancy
!
!
interface FastEthernet0/0
description LAN_LINK
ip address 192.168.1.1 255.255.255.0
ip nat inside
ip virtual-reassembly in
no ip route-cache
speed auto
full-duplex
no mop enabled
!
interface FastEthernet0/1
description WAN_LINK
ip address dhcp
ip nat outside
ip virtual-reassembly in
no ip route-cache cef
duplex auto
speed auto
!
interface Serial0/0/0
no ip address
shutdown
!
ip forward-protocol nd
ip http server
ip http authentication local
no ip http secure-server
!
!
ip nat inside source list 102 interface FastEthernet0/0 overload
ip route 0.0.0.0 0.0.0.0 dhcp
!
access-list 102 permit ip 192.168.1.0 0.0.0.255 any
!
!
control-plane
!
!
!
line con 0
password XXXXXX
login
line aux 0
line vty 0 4
login local
transport input all
line vty 5 15
password XXXXXXX
login
transport input all
!
scheduler allocate 20000 1000
end
________________________________________________________________________________-
And here are the statistics from show ip traffic:
hillside.lan#show ip traffic
IP statistics:
Rcvd: 6233 total, 5544 local destination
0 format errors, 0 checksum errors, 0 bad hop count
0 unknown protocol, 1 not a gateway
0 security failures, 0 bad options, 0 with options
Opts: 0 end, 0 nop, 0 basic security, 0 loose source route
0 timestamp, 0 extended security, 0 record route
0 stream ID, 0 strict source route, 0 alert, 0 cipso, 0 ump
0 other
Frags: 0 reassembled, 0 timeouts, 0 couldn't reassemble
0 fragmented, 0 fragments, 0 couldn't fragment
Bcast: 5451 received, 14 sent
Mcast: 0 received, 0 sent
Sent: 182 generated, 533 forwarded
Drop: 22 encapsulation failed, 0 unresolved, 0 no adjacency
129 no route, 0 unicast RPF, 0 forced drop
0 options denied
Drop: 0 packets with source IP address zero
Drop: 0 packets with internal loop back IP address
11 physical broadcast
Reinj: 0 in input feature path, 0 in output feature path
ICMP statistics:
Rcvd: 0 format errors, 0 checksum errors, 0 redirects, 1 unreachable
0 echo, 0 echo reply, 0 mask requests, 0 mask replies, 0 quench
0 parameter, 0 timestamp, 0 timestamp replies, 0 info request, 0 other
0 irdp solicitations, 0 irdp advertisements
0 time exceeded, 0 info replies
Sent: 0 redirects, 125 unreachable, 0 echo, 0 echo reply
0 mask requests, 0 mask replies, 0 quench, 0 timestamp, 0 timestamp replies
0 info reply, 0 time exceeded, 0 parameter problem
0 irdp solicitations, 0 irdp advertisements
TCP statistics:
Rcvd: 48 total, 0 checksum errors, 1 no port
Sent: 47 total
BGP statistics:
Rcvd: 0 total, 0 opens, 0 notifications, 0 updates
0 keepalives, 0 route-refresh, 0 unrecognized
Sent: 0 total, 0 opens, 0 notifications, 0 updates
0 keepalives, 0 route-refresh
EIGRP-IPv4 statistics:
Rcvd: 0 total
Sent: 0 total
PIMv2 statistics: Sent/Received
Total: 0/0, 0 checksum errors, 0 format errors
Registers: 0/0 (0 non-rp, 0 non-sm-group), Register Stops: 0/0, Hellos: 0/0
Join/Prunes: 0/0, Asserts: 0/0, grafts: 0/0
Bootstraps: 0/0, Candidate_RP_Advertisements: 0/0
Queue drops: 0
State-Refresh: 0/0
IGMP statistics: Sent/Received
Total: 0/0, Format errors: 0/0, Checksum errors: 0/0
Host Queries: 0/0, Host Reports: 0/0, Host Leaves: 0/0
DVMRP: 0/0, PIM: 0/0
Queue drops: 0
UDP statistics:
Rcvd: 5495 total, 0 checksum errors, 5413 no port
Sent: 14 total, 0 forwarded broadcasts
OSPF statistics:
Last clearing of OSPF traffic counters never
Rcvd: 0 total, 0 checksum errors
0 hello, 0 database desc, 0 link state req
0 link state updates, 0 link state acks
Sent: 0 total
0 hello, 0 database desc, 0 link state req
0 link state updates, 0 link state acks
ARP statistics:
Rcvd: 4550 requests, 49 replies, 0 reverse, 0 other
Sent: 14 requests, 67 replies (0 proxy), 0 reverse
Drop due to input queue full: 0
Solved! Go to Solution.
09-30-2015 01:55 PM
You are referencing the wrong interface in your NAT statement ie. you should be referencing the interface with "ip nat outside" on it not "ip nat inside".
Jon
09-30-2015 01:55 PM
You are referencing the wrong interface in your NAT statement ie. you should be referencing the interface with "ip nat outside" on it not "ip nat inside".
Jon
09-30-2015 02:03 PM
Is this the reference you are talking about?
ip nat inside source list 102 interface FastEthernet0/0 overload
ip route 0.0.0.0 0.0.0.0 dhcp
So I would reference it as:
ip nat outside source list 102 interface FastEthernet0/0 overload
ip route 0.0.0.0 0.0.0.0 dhcp
Is that the only mistake I've made?
09-30-2015 02:07 PM
It is the reference but I didn't explain it very well ie. it should be -
"ip nat inside source list 102 interface fa0/1 overload"
note the actual interface being used.
Can't see anything else obviously wrong assuming your clients have a DNS server in their configuration for resolving internet addresses.
Jon
09-30-2015 02:12 PM
Yes, I have an internal DNS and DHCP server. Sorry, I didn't think to mention that. I have to disconnect to try that config change.
09-30-2015 02:32 PM
Thank you, Jon.
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide