Configuring a 3945 Router's Gigabit Ports for internet connectivity.

[RBM01991]

Team, I would like to use gi0/2 as a way to get my internet in from my ISP. The ONT has an Ethernet port on it, that is currently connected to an HWIC-1FE card which provides me with 100 mbps. Since I'm going to upgrade to 500 mbps, and possibly Gigabit, I need to have a compatible port on this router. Can anyone provide me with some configuration steps on how to do it?

Here's the running config on my router at the moment. Thanks in advance!

Building configuration...


Current configuration : 2671 bytes
!
! Last configuration change at 10:43:44 EST Thu Jan 2 2020
!
version 15.7
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname HomeRouter-001
!
boot-start-marker
boot system flash:c3900-universalk9-mz.SPA.157-3.M5.bin
boot-end-marker
!
!
enable secret 5 $1$d.au$f/puBghk0fn9ztVqTehNn.
!
no aaa new-model
clock timezone EST -5 0
!
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!


!
ip dhcp excluded-address 192.168.1.1 192.168.1.30
!
ip dhcp pool internal
 network 192.168.1.0 255.255.255.0
 default-router 192.168.1.1
 dns-server 8.8.8.8 8.8.4.4
 netbios-name-server 192.168.1.1
 lease infinite
!
ip dhcp pool internal2
 network 192.168.2.0 255.255.255.0
 default-router 192.168.2.1
 dns-server 8.8.8.8 8.8.4.4
 netbios-name-server 192.168.2.1
 lease infinite
!
!
!
ip name-server 8.8.8.8
ip name-server 8.8.4.4
ip cef
no ipv6 cef
!
!
multilink bundle-name authenticated
!
!
!
!
!
!
voice-card 0
!
!
!
!
!
!
!
!
vxml logging-tag
license udi pid C3900-SPE150/K9 sn FOC15505HWS
license accept end user agreement
license boot module c3900 technology-package datak9
!
!
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redundancy
!
!
!
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!
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interface Embedded-Service-Engine0/0
 no ip address
 shutdown
!
interface GigabitEthernet0/0
 ip address 192.168.1.1 255.255.255.0
 ip nat inside
 ip virtual-reassembly in
 duplex auto
 speed auto
!
interface GigabitEthernet0/1
 ip address 192.168.2.1 255.255.255.0
 ip nat inside
 ip virtual-reassembly in
 duplex auto
 speed auto
!
interface GigabitEthernet0/2
 ip address dhcp
 ip access-group ISP in
 ip nat outside
 ip virtual-reassembly in
 duplex auto
 speed auto
!
interface FastEthernet0/0/0
 description INTERNET
 ip address dhcp
 ip access-group MY-WAN in
 ip nat outside
 ip virtual-reassembly in
 duplex auto
 speed auto
!
!
ip forward-protocol nd
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no ip http server
no ip http secure-server
!
ip dns server
ip nat inside source list 1 interface FastEthernet0/0/0 overload
!
ipv6 ioam timestamp
!
nls resp-timeout 1
cpd cr-id 1
!
access-list 1 permit 192.168.1.0 0.0.0.255
access-list 1 permit 192.168.2.0 0.0.0.255
!
control-plane
!
 !
 !
 !
 !
!
mgcp behavior rsip-range tgcp-only
mgcp behavior comedia-role none
mgcp behavior comedia-check-media-src disable
mgcp behavior comedia-sdp-force disable
!
mgcp profile default
!
!
!
!
!
!
!
gatekeeper
 shutdown

[paul driver]

Hello
You could possibly procure a wan card for one for the EHWIC slots and use that, or if the router has any spare sfp slots use a 1gb copper sfp?

[RBM01991]

I have an EHWIC-4SG card installed in the router, but it doesn't show up in my interfaces and I can't figure out why. I was going to use that, until someone told me that I could use the regular ports on the router to do what I'm trying to do.

[paul driver]

Hello

---

@RBM01991 wrote:

I have an EHWIC-4SG card installed in the router, but it doesn't show up in my interfaces and I can't figure out why.

Is that card compatible for that router?
Have you tried another HWIC slot?
Have you rebooted the router after inserting the card?

---

@RBM01991 wrote:

 until someone told me that I could use the regular ports on the router to do what I'm trying to do.

---

You can if you have any spare?

sh inventory
sh version
sh ip int brief

[RBM01991]

I've done all 3 of those and the card still doesn't show up, however if I do sh inventory or sh diag, it comes up there.

[balaji.bandi]

If you have done all the steps suggest, this module is not hot-swappable as per my experience. and you able to see the show inventory.

then try other suggestions as per the below and let us know how it goes?

https://www.cisco.com/c/en/us/td/docs/routers/access/interfaces/software/feature/guide/eesm_sw.html#71280

You still have an issue, please show below information :

show inventory

show interfaces

show license

[RBM01991]

I'll try those in the morning, thank you.

[RBM01991]

I also do have a Gigabit port on the router itself free, I have Gigabit 0/0 connected to my switch, Gigabit 0/1 connected to my server and Gigabit 0/2 is free and its the one I intend on using for this purpose.

[balaji.bandi]

if the ports are free you can use them too. (i do not see any issue here)

[RBM01991]

Ok, so would I configure gi0/2 in this instance?

[balaji.bandi]

you have come configuration already as below :

interface GigabitEthernet0/2
 ip address dhcp
 ip access-group ISP in
 ip nat outside
 ip virtual-reassembly in
 duplex auto
 speed auto

make appropriate changes and test it, make sure you change the routing from your FastEther to the new port and adjust the config accordingly.

[RBM01991]

Ok, so I did that, but what do you mean change the routing from FE to the new port?

[balaji.bandi]

since OLD connection connected to FE port, now you moved to Gig Port, so make necessary changes if required to go to internet using new port i mean.

[paul driver · Accepted solution]

Hello

If you want to swap the port around well that can be done but you need to change any routing (dynamic/static) any nat configuration pointing to the old interface to the new interface, plus keep in mind your going from a 100mb fastethernet to gigabitethernet so the otherside of the connection needs to be able to support gigabit otherwise you will have to hardcode the gigabit interface down to a lower speed

Example

conf t
default interface gig0/2
default inerface fa0/0/0
no ip nat inside source list 1 interface FastEthernet0/0/0 overload
no ip route 0.0.0.0 0.0.0.0 FastEthernet0/0/0 dhcp

interface GigabitEthernet0/2
description INTERNET
ip address dhcp
ip access-group MY-WAN in
ip nat outside

interface FastEthernet0/0/0
ip address dhcp
ip access-group ISP in
ip nat outside

ip nat inside source list 1 interface GigabitEthernet0/2 overload
ip route 0.0.0.0 0.0.0.0 FastEthernet0/0/0 dhcp

[RBM01991]

Unfortunatelly that didn't work, as soon as I copied and pasted that configuration and switched the cable over from FE to GI0/2, I lost complete internet connectivity.