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DSL Router With External Modem - Static IP

rdtech

one in my vpn location I'am using cisco router config with dynamic ip address

can anyone help me to config this router using static ip address using verizon modem

Thank You

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Comments

nice343

IF you are receving dynamic IP from Verizon the only way that can be changed is if you talk to them that you want to make it a static. No configuration will make that Public Ip a static till you talk to Verizon

rdtech

I need to config the cisco router with static ip address
I do have the ip and default gateway address

before I was using cable modem using dynamic ip

dtlokee

Is this what you're looking for?

interface fa0/0 ! whatever interface id
ip address 10.1.1.1 255.255.255.0
!
ip route 0.0.0.0 0.0.0.0 1.2.3.4 ! replace the 1.2.3.4 with your default gateway.

rdtech

How to remove the dhcp client from the interface
thank you

dtlokee

Use the "ip address" command to configure the static IP address and it will remove th command automatically, or you can use the "no ip address dhcp" command but you will not have an IP address at that point.

You may want to explore the implications of what you're doing a little more, do you have an ACL in place to provide securty of some type as well as a NAT configuration to allow your hosts access to the Internet? I only ask because chainging an IP address is basc compared to these other tasks.

nice343

a any cisco router which is receiving an Ip from a dhcp is configured as

inter f0/0
ip address dhcp

if you want the interface to stop receiving ip dynamically just go into the interface and type

no ip address dhcp

rdtech

I had a comcast cable modem hook up to the cisco router Ethernet port, the modem is doing Dhcp
and the router config with nat and vpn.

I need to change the dynamic ip address to static Ip address by using a verizion Modem

Thank you

rdtech

I have AcL and NAT config inside the router

Thank you for your help

rdtech

Site01#sh run
Building configuration...

Current configuration : 1827 bytes
!
version 12.3
no service pad
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname site01
!
enable secret 5 eyuiioqooadldaldada./
!
no aaa new-model
ip subnet-zero
!
!
ip audit notify log
ip audit po max-events 100
no ftp-server write-enable
!
!
!
!
crypto isakmp policy 1
hash md5
authentication pre-share
crypto isakmp key 0 cr4456002 address 23.4.7.66
!
!
crypto ipsec transform-set pix-set esp-des esp-md5-hmac
crypto ipsec df-bit clear
!
crypto map pix 10 ipsec-isakmp
set peer 23.4.7.66
set transform-set pix-set
match address 101
!
no crypto engine accelerator
!
!
!
interface Ethernet0
ip address 192.168.212.254 255.255.240.0
ip nat inside
no cdp enable
hold-queue 32 in
!
interface Ethernet1
ip address dhcp client-id Ethernet1
ip nat outside
duplex auto
no cdp enable
crypto map pix
!
interface FastEthernet1
no ip address
duplex auto
speed auto
!
interface FastEthernet2
no ip address
duplex auto
speed auto
!
interface FastEthernet3
no ip address
duplex auto
speed auto
!
interface FastEthernet4
no ip address
duplex auto
speed auto
!
ip nat inside source route-map nonat interface Ethernet1 overload
ip classless
ip http server
no ip http secure-server
!
access-list 23 permit 192.168.0.0 0.0.255.255
access-list 23 permit 70.75.68.128 0.0.0.x
access-list 101 permit ip 192.168.224.0 0.0.15.255 172.16.0.0 0.0.15.255
access-list 110 deny ip 192.168.224.0 0.0.15.255 172.16.0.0 0.0.15.255
access-list 110 permit ip 192.168.224.0 0.0.15.255 any
no cdp run
route-map nonat permit 10
match ip address 110
!
!
line con 0
exec-timeout 120 0
no modem enable
stopbits 1
line aux 0
line vty 0 4
access-class 23 in
exec-timeout 120 0
password 7 566666
login
!
scheduler max-task-time 5000
!
end

mgeorge

What kind of router/ios ?

Well from the looks of the configuration you are using the dsl modem to perform the PPPoE dialer.

You may want to consider bringing the pppoe dialer to the router and configure the modem as a bridge only. The the dialerX interface to the ethernet port which the modem is attached. This would give you more grainular control over the pppoe dialer. mtu, timeouts, security, etc...

If verizon is anything like AT&T, they will provide you your static ip via dhcp as well. So if you do choose to configure the pppoe dialer on the router, configure it to "ip address negotiated" and you will receive the static ip address they provided you via dhcp. With the dialer set to persistant, it will attempt reconnection immediately after a session is dropped. With ya typical dsl modem/router box, they have a grace period of 5 seconds.

the PPPoE dialer is only supported in 12.3 ip plus or greater. you can check via feature navigator

You may want to check with your modem and make sure it is not providing a private ip address when using "ip address dhcp" on your cisco router, if this is the case, then your traffic is getting nat'ted twice and will cause ipsec problems.

Hope this points you in the right direction

vjsousa

The modem type or the ISP doesn't matter. The modem is just a bridging device and doesn't perfor m routing.

What type of Cisco router? I have a PIX at home and I used the following configuration for a static IP address:

ip address outside x.x.x.x 255.255.255.0
ip address inside 192.168.1.1 255.255.255.0

route outside 0.0.0.0 0.0.0.0 next hop (default gateway)

mgeorge

vjsousa wrote:

The modem type or the ISP doesn't matter. The modem is just a bridging device and doesn't perfor m routing.

What type of Cisco router? I have a PIX at home and I used the following configuration for a static IP address:

Most of the dsl modems now days perform EVERYTHING; wireless, dhcp, nat, routing, firewall services and more.

All modems provided by Bellsouth/ATT, Quest, Windstream Communications will perform NAT at the modem its self and provide private dhcp addresses by default. (Unless it's configured to bridge)

Clearly from the configurarion provided, this is a router not a firewall. As you see the router is running 12.3 (firewalls dont run 12.3)

Although you are given a static ip address, this static ip address is typically issued via DHCP with most dsl providers, static IP's via DHCP are bound to your username. So upon authentication and dhcp request, you will receive the static ip(s) you've been alloted.

rdtech

Thank you to all of you I got it to work

Below is the config I got from Dtlokee:

interface fa0/0 ! whatever interface id
ip address 10.1.1.1 255.255.255.0
!
ip route 0.0.0.0 0.0.0.0 1.2.3.4 !

replace the 1.2.3.4 with your default gateway.

dtlokee

mgeorge27 wrote:

As you see the router is running 12.3 (firewalls dont run 12.3)

12.3 has an IOS FW version.

mgeorge

I meant as a firewall app :P pix or asa, netscreen etc... ^_^

almost time for the game!!! supposed to be 3 degree's at kick off!!!