12-24-2018 09:00 PM - edited 03-08-2019 04:53 PM
cisco c3825 router connected to Motorola cable modem MB8600 connected with xfinity Residental for Internet on Gi0/0 and 3560G with POE connected for internal on Gi0/1. I am attempting to ping 8.8.8.8 which is google and fails but I am able to ping the modem's default gateway. I am unable to get internet access from the router and is unable to proceed any further until then. I have verified that there is internet and verified the modem is working.
C3825Router#ping 8.8.8.8
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 8.8.8.8, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
C3825Router#show run
Building configuration...
Current configuration : 7777 bytes
!
version 15.1
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname C3825Router
!
boot-start-marker
boot-end-marker
!
!
!
no aaa new-model
!
!
dot11 syslog
ip source-route
!
ip cef
!
!
ip dhcp excluded-address 10.10.25.1 10.10.25.15
ip dhcp excluded-address 10.10.35.1 10.10.35.15
!
ip dhcp pool Data
network 10.10.25.0 255.255.255.0
default-router 10.10.25.1
option 66 ip 10.10.25.1
option 150 ip 10.10.25.1
dns-server 1.1.1.1 1.0.0.1
!
ip dhcp pool Voice
network 10.10.35.0 255.255.255.0
default-router 10.10.35.1
option 66 ip 10.10.35.1
option 150 ip 0.10.35.1
dns-server 1.1.1.1 1.0.0.1
!
!
no ip domain lookup
ip name-server 75.75.75.75
ip name-server 75.75.76.76
no ipv6 cef
!
multilink bundle-name authenticated
!
!
!
!
!
voice-card 0
!
!
!
voice service voip
ip address trusted list
ipv4 0.0.0.0 0.0.0.0
allow-connections h323 to h323
allow-connections h323 to sip
allow-connections sip to h323
allow-connections sip to sip
sip
registrar server expires max 3600 min 120
!
!
voice register global
mode cme
source-address 10.10.35.9 port 5060
max-dn 40
max-pool 42
tftp-path flash:
create profile sync 000084074536341A
!
voice register dn 1
number 2001
allow watch
name PH-2001
label 2001
mwi
!
voice register dn 2
number 2002
allow watch
name PH-2002
label 2002
mwi
!
voice register dn 3
number 2003
allow watch
name PH-2003
label 2003
mwi
!
voice register dn 4
number 2004
allow watch
name PH-2004
label 2004
mwi
!
voice register dn 5
number 2005
allow watch
name PH-2005
label 2005
mwi
!
voice register dn 6
number 2006
allow watch
name PH-2006
label 2006
mwi
!
voice register dn 7
number 2007
allow watch
name PH-2007
label 2007
mwi
!
voice register dn 8
number 2008
allow watch
name PH-2008
label 2008
mwi
!
voice register dn 9
number 2009
allow watch
name PH-2009
label 2009
mwi
!
voice register dn 10
number 2010
allow watch
name PH-2010
label 2010
mwi
!
!
!
!
crypto pki token default removal timeout 0
!
!
!
!
license udi pid CISCO3825 sn FTX0937A3DP
!
redundancy
!
!
!
!
!
!
!
!
!
!
interface GigabitEthernet0/0
description WAN
ip address 192.168.100.200 255.255.255.0
ip nat outside
ip virtual-reassembly in
duplex auto
speed auto
media-type rj45
!
interface GigabitEthernet0/1
description LAN
no ip address
duplex auto
speed auto
media-type rj45
!
interface GigabitEthernet0/1.25
description LAN-Data
encapsulation dot1Q 1 native
ip nat inside
ip virtual-reassembly in
!
interface GigabitEthernet0/1.35
description LAN-Voice
encapsulation dot1Q 2
ip nat inside
ip virtual-reassembly in
!
ip forward-protocol nd
no ip http server
no ip http secure-server
!
!
ip nat inside source list 101 interface GigabitEthernet0/0 overload
ip route 0.0.0.0 0.0.0.0 192.168.100.1
!
logging esm config
access-list 101 permit ip 10.10.0.0 0.0.255.255 any
!
!
!
!
!
!
control-plane
!
!
voice-port 0/0/0
!
voice-port 0/0/1
!
voice-port 0/0/2
!
voice-port 0/0/3
!
voice-port 0/1/0
!
voice-port 0/1/1
!
voice-port 0/1/2
!
voice-port 0/1/3
!
!
!
mgcp profile default
!
!
!
sip-ua
credentials number 13098635246 username GV13098635246 password 7 08764E5A5F03242137005E3D2227 realm GVGW
authentication username GV13098635246 password 7 073529187A031A5D433A331D35
registrar dns:gvgw3.simonics.com:5070 expires 1800 tcp
sip-server dns:gvgw3.simonics.com:5070
!
!
!
telephony-service
moh-file-buffer 2000
max-ephones 30
max-dn 50
ip source-address 10.10.35.2 port 2000
ip qos dscp af31 signal
service dnis overlay
service dnis dir-lookup
timeouts interdigit 2
system message Ciscoland.net
cnf-file location flash:
load 7960-7940 P00308010200
load 7941 SCCP41.9-3-1SR4-1S
load 7942 SCCP42.9-3-1SR4-1S
load 7945 SCCP45.9-2-1S
load 7961 SCCP41.9-3-1SR4-1S
load 7962 SCCP42.9-3-1SR4-1S
load 7965 SCCP45.9-3-1SR4-1S
dialplan-pattern 1 5... extension-length 4
max-conferences 4 gain -6
moh music-on-hold.au
multicast moh 239.1.1.1 port 2000 route 10.10.25.1 10.10.35.1
dn-webedit
time-webedit
transfer-system full-consult
secondary-dialtone 9
directory entry 1 2580 name Human Resources
directory entry 2 2648 name IT Help Desk
directory entry 3 2860 name Security
directory entry 4 4286 name Front Desk
directory entry 5 8620 name Grounds Maintence
directory entry 6 8684 name Confrence Room
directory entry 7 2448 name Break Roon
directory entry 8 2864 name Building Maintence
directory entry 9 4884 name Computer Room
directory entry 10 8684 name Living Room
directory entry 11 2448 name Kitchen
directory entry 12 2864 name Bedroom 2 - Brandon
directory entry 13 8888 name Server/Networking Room
directory entry 14 8666 name DJ Laptop
!
!
ephone-dn 1 dual-line
number 2580
label 2580
description Human Resources
name Human Resources
hold-alert 30 originator
!
!
ephone-dn 2 dual-line
number 2648
label 2648
description IT Help Desk
name IT Help Desk
hold-alert 30 originator
!
!
ephone-dn 3 dual-line
number 2860
label 2860
description Security
name Security
hold-alert 30 originator
!
!
ephone-dn 4 dual-line
number 4286
label 4286
description Front Desk
name Front Desk
hold-alert 30 originator
!
!
ephone-dn 5 dual-line
number 4884
label 4884
description Computer Room
name Computer Room
hold-alert 30 originator
!
!
ephone-dn 6 dual-line
number 8684
label 8684
description Living Room
name Living Room
hold-alert 30 originator
!
!
ephone-dn 7 dual-line
number 2448
label 2448
description Kitchen
name Kitchen
hold-alert 30 originator
!
!
ephone-dn 8 dual-line
number 2864
label 2864
description Bedroom 2 - Brandon
name Bedroom 2 - Brandon
hold-alert 30 originator
!
!
ephone-dn 9 dual-line
number 8888
label 8888
description Server/Networking Room
name Phone Server/Networking Room
hold-alert 30 originator
!
!
ephone-dn 12 dual-line
number 8666
label DJ Laptop
name DJ Laptop
hold-alert 30 originator
!
!
ephone 1
device-security-mode none
mac-address 000B.BEAD.4D4F
type 7960
button 1:1
!
!
!
ephone 2
device-security-mode none
mac-address 0011.92BA.230B
speed-dial 1 2860 label "Security"
speed-dial 2 2580 label "Human Resources"
speed-dial 3 4286 label "Front Desk"
speed-dial 4 1010 label "Lab"
type 7960
button 1:2
!
!
!
ephone 3
device-security-mode none
mac-address 000F.8FC6.9EE8
type 7960
button 1:3
!
!
!
ephone 4
device-security-mode none
mac-address 000B.BEAD.42CF
type 7960
button 1:4
!
!
!
ephone 5
device-security-mode none
mac-address C062.6BD3.2E41
type 7945
button 1:5
!
!
!
ephone 6
device-security-mode none
mac-address 0023.339B.F76B
type 7945
button 1:6
!
!
!
ephone 7
device-security-mode none
mac-address 0021.A02C.A957
type 7945
button 1:7
!
!
!
ephone 8
device-security-mode none
mac-address 0021.A02C.C59C
type 7945
button 1:8
!
!
!
ephone 9
device-security-mode none
mac-address 34BD.C82D.4CDB
type 7945
button 1:9
!
!
!
ephone 10
device-security-mode none
!
!
!
ephone 11
device-security-mode none
!
!
!
ephone 12
device-security-mode none
mac-address F01F.AF46.3036
type CIPC
button 1:12
!
!
!
ephone 13
device-security-mode none
!
!
!
ephone 15
device-security-mode none
!
!
!
ephone 17
device-security-mode none
!
!
!
ephone 18
device-security-mode none
!
!
!
alias exec con conf t
alias exec sib show ip int brief
alias exec srb show run | b
alias exec sri show run int
!
line con 0
exec-timeout 0 0
logging synchronous
line aux 0
line vty 0 4
privilege level 15
login
transport input telnet ssh
transport output telnet ssh
line vty 5 15
privilege level 15
login
transport input telnet ssh
transport output telnet ssh
!
scheduler allocate 20000 1000
end
12-24-2018 09:49 PM
Please share the output of the following commands: sh ip int bri , sh ip route, and traceroute 8.8.8.8
HTH,
Meheretab
12-26-2018 01:02 AM
I will run those commands and provide the output as soon as I can
12-26-2018 07:10 AM
C3825Router#sh ip int brief
Interface IP-Address OK? Method Status Protocol
GigabitEthernet0/0 192.168.100.200 YES NVRAM up up
GigabitEthernet0/1 unassigned YES NVRAM up down
GigabitEthernet0/1.25 unassigned YES unset up down
GigabitEthernet0/1.35 unassigned YES unset up down
NVI0 192.168.100.200 YES unset up up
C3825Router#
C3825Router#sh 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 192.168.100.1 to network 0.0.0.0
S* 0.0.0.0/0 [1/0] via 192.168.100.1
192.168.100.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.100.0/24 is directly connected, GigabitEthernet0/0
L 192.168.100.200/32 is directly connected, GigabitEthernet0/0
C3825Router#
C3825Router#traceroute 8.8.8.8
Type escape sequence to abort.
Tracing the route to 8.8.8.8
1 * * *
2 * * *
3 * * *
4 * * *
5 * * *
6 * * *
7 * * *
8 * * *
9 * * *
10 * * *
11 * * *
12 * * *
13 * * *
14 * * *
15 * * *
16 * * *
17 * * *
18 * * *
19 * * *
20 * * *
21 * * *
22 * * *
23 * * *
24 * * *
25 * * *
26 * * *
27 * * *
28 * * *
29 * * *
30 * * *
C3825Router#
12-26-2018 10:57 AM
Could you also provide the output of the command show arp from the router?
HTH
Rick
12-26-2018 06:01 PM
C3825Router#show arp
Protocol Address Age (min) Hardware Addr Type Interface
Internet 192.168.100.1 222 e098.61fd.706b ARPA GigabitEthernet0/0
Internet 192.168.100.200 - 0013.c37c.3350 ARPA GigabitEthernet0/0
C3825Router#show arp sum
C3825Router#show arp summary
Total number of entries in the ARP table: 2.
Total number of Dynamic ARP entries: 1.
Total number of Incomplete ARP entries: 0.
Total number of Interface ARP entries: 1.
Total number of Static ARP entries: 0.
Total number of Alias ARP entries: 0.
Total number of Simple Application ARP entries: 0.
Total number of Application Alias ARP entries: 0.
Total number of Application Timer ARP entries: 0.
Interface Entry Count
GigabitEthernet0/0 2
C3825Router#
12-27-2018 10:25 AM
Thanks for the output. In a previous post there were questions about IP addresses for the subinterfaces (the nat inside interfaces) and gateways. Based on the configured DHCP scopes I believe that we have answers for those questions but suggest that we defer discussing these until we have solved the issue of router access to the Internet.
The static default route and the output of show ip route do show that the router should attempt to access the Internet by going out the Gig0/0 interface. And the output of show ip interface brief does show that this interface is up. So I am surprised that there is no response to the traceroute request.
Can you try to ping the next hop of 192.168.100.1 and post the output.
HTH
Rick
12-27-2018 02:32 PM
12-27-2018 05:03 PM
Please share the output of traceroute 8.8.8.8 source 192.168.100.200
HTH,
Meheretab
12-28-2018 08:46 AM
Thanks for the update that you are successful in ping the cable modem address. I am puzzled why that is successful but ping to 8.8.8.8 is not. Perhaps it might provide helpful information if you enable debug ip packet, try the ping to 8.8.8.8, and post the debug output.
HTH
Rick
12-28-2018 12:18 PM
C3825Router#traceroute 8.8.8.8 source 192.168.100.200
Type escape sequence to abort.
Tracing the route to 8.8.8.8
1 * * *
2 * * *
3 * * *
4 * * *
5 * * *
6 * * *
7 * * *
8 * * *
9 * * *
10 * * *
11 * * *
12 * * *
13 * * *
14 * * *
15 * * *
16 * * *
17 * * *
18 * * *
19 * * *
20 * * *
21 * * *
22 * * *
23 * * *
24 * * *
25 * * *
26 * * *
27 * * *
28 * * *
29 * * *
30 * * *
C3825Router#
12-28-2018 01:27 PM
The gateway does have an entry in the arp table and the router does successfully ping the gateway. So we know there is communication between the router and the gateway. But the gateway does not respond to traceroute. I wonder if there is some security setting in the gateway that prevents response to traceroute? I wonder if that security setting might be impacting other traffic from the router? Perhaps the original poster can talk with their service provider and ask if they have any insight into what might be going on?
HTH
Rick
12-25-2018 12:15 AM
Hello,
The NAT inside interfaces do not have IP addresses, or did you omit that output on purpose ? Where are the default gateways configured ?
12-26-2018 01:01 AM
What addresses should be given to the NAT inside or how should the command be entered? What default gateways are you referring to?
12-29-2018 02:32 PM
Hi,
My view is that Motorola MB8600 is bridge modem only and as such should pass ISP public IP address to the router. So I would try to modify your router configuration as per beneath:
interface GigabitEthernet0/0
ip address dhcp
ip route 0.0.0.0 0.0.0.0 GigabitEthernet0/0 dhcp
Best regards,
Antonin
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