Newbie Routing Question

[DawgnFL]

I have an Internet T1 I am setting up with a Cisco 1720, Ethernet port and WIC1 CSU/DSU. I have it set up to what I think is correct but it is not fully working. From a telnet session to the router I can ping my internal network and I can ping the Internet but I can not get from the local network to the Internet. Here is the config:

version 12.3
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname HI_Remote
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$Ltfl$lwd4t3sOla5hUgJCPBkDu1
enable password ***
!
memory-size iomem 25
no aaa new-model
ip subnet-zero
!
!
!
ip cef
!
!
!
!
interface FastEthernet0
ip address 10.1.5.1 255.255.0.0
speed auto
full-duplex
no cdp enable
!
interface Serial0
ip address 63.***.***.154 255.255.255.252
!
ip classless
ip route 0.0.0.0 0.0.0.0 63.***.***.153
no ip http server
!
access-list 101 permit icmp any any
!
line con 0
exec-timeout 0 0
line aux 0
line vty 0 4
password ***
login
!
!
end

HI_Remote#

THe PC I am using has the IP address of 10.1.5.3 with a gateway of 10.1.5.1

Any reason why this shouldn't work? Encap is set to HDLC on INT S0, I have tried changing the IP ROUTE 0.0.0.0 to the S0 interface but that didn't work either...I'm stuck!

 

[DawgnFL]

Also...I can PING from PC on local network through the FE0 interface to the S0 interface, but not out of that interface to the internet.

 

[lgarner]

You need NAT. Your 10.x.x.x addresses won't work on the Internet.

access-list 101 permit ip any any
ip nat inside source list 101 interface FastEthernet1/0 overload

interface Serial0
ip nat outside

This will translate all outgoing traffic to be "from" your outside interface, so the Internet can find you.

 

[DawgnFL]

OK, I tried that but still the same situation after reload...new config...

version 12.3
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname HI_Remote
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$Ltfl$lwd4t3sOla5hUgJCPBkDu1
enable password ***
!
memory-size iomem 25
no aaa new-model
ip subnet-zero
!
!
!
ip cef
!
!
!
!
interface FastEthernet0
ip address 10.1.5.1 255.255.0.0
speed auto
full-duplex
no cdp enable
!
interface Serial0
ip address 63.***.***.154 255.255.255.252
ip nat outside
!
ip nat inside source list 101 interface FastEthernet0 overload
ip classless
ip route 0.0.0.0 0.0.0.0 Serial0
no ip http server
!
access-list 101 permit icmp any any
access-list 101 permit ip any any
!
line con 0
exec-timeout 0 0
line aux 0
line vty 0 4
password ***
login
!
!
end

HI_Remote#

If I do a tracert on the local LAN PC to external IP address it hits the gateway 10.1.5.1 and then times out from there.

 

[lgarner]

Oops. Change the line
ip nat inside source list 101 interface FastEthernet0 overload
.. to ..
ip nat inside source list 101 interface Serial0 overload

I had pasted my own config and didn't change the interface to match yours. Sorry.

 

[DawgnFL]

No, that still didn't get it...from internal it seems nothing is getting from one interface to the other. Ugh...

 

[IllegalOperation]

You need to put "ip nat inside" on your ethernet interface as well.

LGarner forgot to mention that, a very rare mistake for him. Whats wrong lgarner, hurrying to get out of work for the weekend? =)

 

[lgarner]

D'oh! Thanks for the kind words. Actually, this seems to be a day for the all-too-common brain freeze!