04-28-2012 07:51 AM - edited 03-04-2019 04:11 PM
Hi All,
I have a Cisco 1841 router that is connected to a switch. I have WAN/LAN configured on the router and the switch is handing out internal IP's.
The issus that none of the client machines can access the Internet. From within the router console, I am able to ping external domain names, my ISP DNS servers.
Once the client machines picks up an IP they are unable to ping any external domain names or IP's and not even the ISP DNS servers, but they can ping the Cisco router IP. As a note I have tried my ISP DNS servers and as a test Google's DNS servers, but neither will allow access to the Internet.
I have checked google looking for an answer on why, but I am missing something I just don't know why. Any help would be helpful.
Thanks,
Ron
Below is the current running config:
Building configuration...
Current configuration : 1440 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname cisco
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$qY4A$6u.zFbIIHacEB51di1Sda.
enable password astec72
!
no aaa new-model
no ip routing
no ip cef
!
!
no ip dhcp use vrf connected
ip dhcp excluded-address 10.10.10.1 10.10.10.14
ip dhcp excluded-address 10.10.10.51 10.10.10.254
!
ip dhcp pool SpyTraer
import all
network 10.10.10.0 255.255.255.0
default-router 10.10.10.1
dns-server 8.8.8.8 8.8.4.4
!
!
ip name-server 8.8.8.8
ip name-server 8.8.4.4
!
!
!
!
!
!
interface FastEthernet0/0
description $ETH-LAN$
ip address 10.10.10.1 255.255.255.0
ip nat inside
no ip route-cache
speed auto
half-duplex
no cdp enable
no mop enabled
!
interface FastEthernet0/1
description $ETH-WAN$
ip address dhcp client-id FastEthernet0/1
ip nat outside
no ip route-cache
duplex auto
speed auto
no cdp enable
!
ip forward-protocol nd
ip route 0.0.0.0 0.0.0.0 FastEthernet0/1 permanent
!
!
ip http server
no ip http secure-server
ip nat inside source list 1 interface FastEthernet0/1 overload
!
access-list 1 remark CCP_ACL Category=2
access-list 1 permit any
snmp-server community public RO
!
!
!
control-plane
!
!
!
line con 0
exec-timeout 0 0
line aux 0
line vty 0 4
password astec
login
!
scheduler allocate 20000 1000
no process cpu extended
no process cpu autoprofile hog
end
04-28-2012 06:19 PM
spped 100
full-duplex
04-28-2012 06:20 PM
Can you post:
sh int fa0/1
sh int fa0/0
sh ip route
sh ip nat trans
04-28-2012 06:50 PM
I can bet that the switch has 100 , half-duplex auto-negociated
After you check , set on the router's interface.
default speed
default duplex
Dan
04-28-2012 07:55 PM
Dan,
Sorry I am new to Cisco. What would be the command to run from the router?
04-28-2012 09:28 PM
Hi Dan,
After running the commands you suggested I am still experncing 40% packet loss on pings and very slow Internet browsing speed.
Thanks,
Ron
04-29-2012 02:10 PM
On the link between the two interfaces where the packet loss is occurring, one of two things is going on
you must have half duplex being set for some reason...which is incorrect....make absolutely sure both of the links are hard set to the same parameters...if that is not the problem, there must be something physically wrong with the fiber or copper between the two interfaces..if a fiber link...have the light levels tested at both ends to verify no more than 4db light difference between the two ends...or you will start getting errors and dropped packets.
Sent from Cisco Technical Support iPad App
04-29-2012 02:52 PM
Hi Charlie,
I just ran show inf and both links are showing
Full-duplex, 100Mb/s 100BaseTX/FX
MTU 1500 bytes, BW 100000 Kbit
I have also changed out the switch that I had in place with another switch and the same speed issues remain.
Thanks,
Ron
04-29-2012 03:59 PM
Ron,
Do you lose packets if you ping 4.2.2.1 from the router? Try this:
ping 4.2.2.1 rep 5000
Let me know how this goes...
John
04-29-2012 05:50 PM
Hi John,
Success rate is 48 percent (1295/2684), rounf-trip min/avg/max = 4/4/200 ms
04-28-2012 06:57 PM
Sorry for the delay
cisco#sh int fa0/1
FastEthernet0/1 is up, line protocol is down
Hardware is Gt96k FE, address is 0023.ebd6.7e71 (bia 0023.ebd6.7e71)
Description: $ETH-WAN$
Internet address is 108.174.105.127/24
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Auto-duplex, Auto Speed, 100BaseTX/FX
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:03:58, output 00:03:00, 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
3095 packets input, 1753793 bytes
Received 212 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog
0 input packets with dribble condition detected
3540 packets output, 321416 bytes, 0 underruns
0 output errors, 0 collisions, 5 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
cisco#
cisco#sh int fa0/0
FastEthernet0/0 is up, line protocol is up
Hardware is Gt96k FE, address is 0023.ebd6.7e70 (bia 0023.ebd6.7e70)
Description: $ETH-LAN$
Internet address is 10.10.10.1/24
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s, 100BaseTX/FX
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:01:41, output 00:00:03, 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
9866 packets input, 1208741 bytes
Received 1395 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog
0 input packets with dribble condition detected
6692 packets output, 2740942 bytes, 0 underruns
0 output errors, 41 collisions, 8 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
cisco#sh ip route
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
10.0.0.0/24 is subnetted, 1 subnets
C 10.10.10.0 is directly connected, FastEthernet0/0
S* 0.0.0.0/0 is directly connected, FastEthernet0/1
cisco#
cisco#sh ip nat trans
Pro Inside global Inside local Outside local Outside global
tcp 108.174.105.127:50105 10.10.10.18:50105 208.48.254.107:80 208.48.254.107:80
tcp 108.174.105.127:50109 10.10.10.18:50109 208.28.224.10:80 208.28.224.10:80
tcp 108.174.105.127:50317 10.10.10.18:50317 208.28.224.18:80 208.28.224.18:80
tcp 108.174.105.127:50345 10.10.10.18:50345 65.55.121.241:80 65.55.121.241:80
tcp 108.174.105.127:50347 10.10.10.18:50347 65.55.239.146:80 65.55.239.146:80
tcp 108.174.105.127:50348 10.10.10.18:50348 208.28.224.49:80 208.28.224.49:80
tcp 108.174.105.127:50427 10.10.10.18:50427 173.194.37.32:443 173.194.37.32:443
tcp 108.174.105.127:50429 10.10.10.18:50429 184.28.190.176:443 184.28.190.176:443
tcp 108.174.105.127:50434 10.10.10.18:50434 184.28.190.176:443 184.28.190.176:443
tcp 108.174.105.127:50445 10.10.10.18:50445 184.28.98.176:443 184.28.98.176:443
tcp 108.174.105.127:50447 10.10.10.18:50447 184.28.98.176:443 184.28.98.176:443
tcp 108.174.105.127:50450 10.10.10.18:50450 184.28.98.176:443 184.28.98.176:443
tcp 108.174.105.127:50501 10.10.10.18:50501 184.28.212.176:443 184.28.212.176:443
tcp 108.174.105.127:50505 10.10.10.18:50505 184.28.212.176:443 184.28.212.176:443
tcp 108.174.105.127:50509 10.10.10.18:50509 184.28.212.176:443 184.28.212.176:443
tcp 108.174.105.127:50511 10.10.10.18:50511 184.28.212.176:443 184.28.212.176:443
tcp 108.174.105.127:50513 10.10.10.18:50513 184.28.212.176:443 184.28.212.176:443
tcp 108.174.105.127:50524 10.10.10.18:50524 184.28.212.176:443 184.28.212.176:443
tcp 108.174.105.127:50533 10.10.10.18:50533 65.54.93.17:80 65.54.93.17:80
04-29-2012 04:03 AM
I would delete the static default route :
no ip route 0.0.0.0 0.0.0.0 fa0/1 dhcp
And any default route configured. The default route is automatically configured from the information received via the DHCP.
Fa0/1 is and ethernet segment and you do not have any next hop set, just the interface.
Dan
04-29-2012 06:01 PM
Hi John and Dan,
I finally got it working. Per Dan's request to delete the static routes, I did not delete the static route, but instead I entered the forwarding next hop as the ISP gateway address (IP Address) and that fixed it.
Thank you both for your time and effort on this matter.
Regards,
Ron
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