Cannot ping public ip after splitting data traffic and voip traffic

[khhhhhhhh957]

Hi,

I am usig cisco 2911 with dual WAN connection to the internet (One modem in "dmz mode" with public ip fix, and one modem in "normal mode" with dynamic ip public).I send all voice traffic accross one link and Data traffic to other internet connection.

Everything in the LAN works. DATA traffic goes through the right path and VOIP too. The problem is that since the external, when I ping my ip address public 217.11.40.106 it does not always respond. Sometimes this answers and sometimes not. And I noticed that everything depends on the external place where I ping it will work or not. 

Do you have any idea of the problem ?

In attachment, this is my config router and my schema

[Georg Pauwen]

Hello,

you have to default routes and CEF enabled, which means that load balancing is being performed.

Where does:

ip route 0.0.0.0 0.0.0.0 192.168.1.1

point to ? I don't see a corresponding interface from the same subnet in your router config.

Also, ypu might want to try route maps for your NAT:

ip nat inside source route-map DATA interface GigabitEthernet0/1 overload
!
route-map DATA permit 10
match ip address 24
match interface GigabitEthernet0/1

ip nat inside source route-map VOICE interface GigabitEthernet0/2 overload
!
route-map VOICE permit 10
match ip address 25
match interface GigabitEthernet0/2

[khhhhhhhh957]

Hi,

Thank you very much for your reply !

The route ip route 0.0.0.0 0.0.0.0 192.168.1.1 points to the voice modem interface. It's correct ?

[Georg Pauwen]

Hello,

from where are you pinging the default gateway 217.11.40.106 when it doesn't respond ?

Which interface is 192.168.1.1 connected to ? That is, which interface is the voice modem connected to ?

[khhhhhhhh957]

Hi,

I tried ping the default gateway 217.11.40.106 from different external locations. On some it works and on others it doesn't work.

The 192.168.1.1  is the address of lan interface of the modem. The modem gives a dhcp address 192.168.1.x to my interface gigabitethernet0/2 of my router.

It's correct for you ?

[Georg Pauwen]

Hello,

when I ping the IP address with the default of 1500, I don't get a response. Try to ping with 1472:

C:\windows\system32>ping -l 1472 217.11.40.106 -f

Pinging 217.11.40.106 with 1472 bytes of data:
Reply from 217.11.40.106: bytes=1472 time=42ms TTL=245
Reply from 217.11.40.106: bytes=1472 time=42ms TTL=245

Ping statistics for 217.11.40.106:
Packets: Sent = 2, Received = 2, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 42ms, Maximum = 42ms, Average = 42ms
Control-C
^C
C:\windows\system32>ping -l 1474 217.11.40.106 -f

Pinging 217.11.40.106 with 1474 bytes of data:
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.

Ping statistics for 217.11.40.106:
Packets: Sent = 2, Received = 0, Lost = 2 (100% loss),

[khhhhhhhh957]

Hi,

Currently I haven't connected the gigabitethernet0/2 interface to the modem. I'll do it this weekend. I just wanted to be sure that when I do it will work.

[Georg Pauwen · Accepted solution]

Hello,

just to be sure, when you say you ping from an external location,do you mean the public Internet ? That is, which source IP are you pinging from ?

[khhhhhhhh957]

Hi,

When I say that I ping from the outside, is that I am in another network and another provider than the 217.11.40.106

[Georg Pauwen]

Hello,

can you ping the sites when you use the lower packet size ?

[khhhhhhhh957]

Hi, 

I tried the command no ip cef, but when I do that, I can no longer ping 8.8.8.8 from the lan