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Can't ping ISP router anymore

John Cheetley
Level 3
Level 3

Hi Team,

This is all for the purpose of SIP connectivity so am assuming that you do need to be able to have ping established connection for SIP to progress too

Unfortunately I have lost access to my ISP's router of 220.233.1.203

My set up is this

ISP router 192.168.20.1

Cisco 2691 MPS router 192.168.20.2 via FA0/0 to port 3 on router

This is a double NAT environment but have added 192.168.20.2 IP to the DMZ in the Firewall

Below is the current routing table

CiscoCurious#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

C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.11.0/24 is directly connected, FastEthernet0/1.1
C 192.168.20.0/24 is directly connected, FastEthernet0/1.10
CiscoCurious#

 

Some commands I have run are...

CiscoCurious(config)#ip route 203.1.233.220 255.255.255.0 192.168.20.2
%Inconsistent address and mask

CiscoCurious(config)#ip route 203.1.233.220 255.255.255.0 192.168.20.1
%Inconsistent address and mask
CiscoCurious(config)#

CiscoCurious(config)#ip route 203.1.233.220 255.255.255.0 FA0/0
%Inconsistent address and mask
CiscoCurious(config)#

CiscoCurious(config)#ip route 203.1.233.220 255.255.255.0 FA0/0 permanent
%Inconsistent address and mask
CiscoCurious(config)#

The last one resulted in this change

 

"Gateway of last resort is 0.0.0.0 to network 0.0.0.0"

C 192.168.30.0/24 is directly connected, FastEthernet0/0
C 192.168.11.0/24 is directly connected, FastEthernet0/1.1
C 192.168.20.0/24 is directly connected, FastEthernet0/1.10
And this "S* 0.0.0.0/0 is directly connected, FastEthernet0/0"
CiscoCurious#

I had thought that ip route destination ip, mask, 192.168.20.1 would have sufficed considering 192.168.20.2 (my cisco router) is already in the ISP router firewall on my side unless I need to use next hop?

Thanks again. If this doesn't make sense, let me know and will assist further

 

22 Replies 22

Hi Deepak,

I cant see anything in the acl either as below shows..

CiscoCurious#show ip access-lists
Standard IP access list 10
10 permit 192.168.20.0, wildcard bits 0.0.0.255
CiscoCurious#

CiscoCurious#ping 192.168.20.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.20.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/4 ms

CiscoCurious#traceroute 192.168.20.1

Type escape sequence to abort.
Tracing the route to 192.168.20.1

1 192.168.20.1 0 msec 0 msec *
CiscoCurious#

 

The ip address for the FA0/0 Link to ISP modem is 192.168.30.2

But the ACL is....
10 permit "192.168.20.0", wildcard bits 0.0.0.255

As the 30 is a different subnet to 20, wouldn't I have to create/modify ACL for this?

Hi,

Some missing configuration on "CiscoCurious"

Q1. Where is IP NAT Inside"?

Please give IP nat Inside command under the required interface as  "FastEthernet0/1.10"

 

Q.2 ISP connected Interface is "FastEthernet 0/0" then where is route?

Ans:  IP route 0.0.0.0 0.0.0.0 192.168.30.1 <ISP modem IP>

 

Q3 Why two more default routes?

Ans: Remove the ip route 0.0.0.0 0.0.0.0 192.168.10.2 & ip route 0.0.0.0 0.0.0.0 203.1.233.220

 

add some spefic static route:

IP route 192.168.15.0 255.255.255.0 192.168.20.2

IP route 192.168.10.0 255.255.255.0 192.168.20.2

 

Make those changes and update me.

 

Regards,

Deepak Kumar

 

 

Regards,
Deepak Kumar,
Don't forget to vote and accept the solution if this comment will help you!

Hi Deepak,

Updated as requested. Thanks in advance :) 

 

Hi,
Routing is not OK

ip default-gateway 203.1.233.220 <Delete it>
ip route 0.0.0.0 0.0.0.0 FastEthernet0/0 < Keep it or toward 192.168.30.1, any one>
ip route 0.0.0.0 0.0.0.0 220.233.1.203 10
ip route 0.0.0.0 0.0.0.0 192.168.20.2 <Delete it>
ip route 0.0.0.0 0.0.0.0 192.168.30.1 <Check the Modem interface IP, Is it correct>
ip route 0.0.0.0 255.255.255.0 192.168.20.2 <Delete It>
ip route 192.168.10.0 255.255.255.0 192.168.20.2
ip route 192.168.15.0 255.255.255.0 192.168.20.2
!

Regards,
Deepak Kumar
Regards,
Deepak Kumar,
Don't forget to vote and accept the solution if this comment will help you!

Hi Deepak,

Thanks again. Will update further tonight. Lots of learning.. :) 

Hi Deepak,

Router updated as attached

Please just clarify ip route 0.0.0.0 0.0.0.0 192.168.30.1 (check modem interface ip..is it correct)..ISP modem is 192.168.20.1

The fa0/0 is 192.168.30.2..

Other entries updates..

 

 

 

Hi,
Then it should be on 20.1 and check the ip nat outside command also.
Regards,
Deepak Kumar
By mobile!
Regards,
Deepak Kumar,
Don't forget to vote and accept the solution if this comment will help you!

Hi Deepak,

Thanks for your help so far. Much appreciated. I have chatted to my ISP re this issue and all route updates we have done and no connection yet to them.

They have asked me to submit a request for assistance to get this connected. So I will leave this open for time being if your OK with that. Let me know.

 

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