WAN on Cisco 877

[info]

Hi,

Is it possible to set up a WAN interface on a FastEthernet interface of a Cisco 877 Adsl Router ?

Due to my ISP, i've to use an external VDSL modem and must connect it to my cisco 877 router (and leave it's adsl interface unused).

But i don't know how to set up a wan port, other than the adsl interface itself (dialer0), on my cisco.

Thanks for any help.

Levente

[paolo bevilacqua · Accepted solution]

Yes, put one Fa port in Vlan2 and configure Vlan2 as needed.

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Yes, thanks. And how can i do that ?

I mean, i know how configure vlan on a FastEthernet port but after ?

I'm a real beginner in cisco word so sorry for that kind of question...

[Latchum Naidu · Accepted solution]

Hi,

Please configure like below to get create the layer 3 interface

interface vlan 1
ip address x.x.x.x x.x.x.x
no shut

interace vlan 2
ip address x.x.x.x x.x.x.x
no shut

Then set the ethernet ports to the appropriate vlans

interface fa0/3
switchport access vlan 1

interface fa0/4
switchport access vlan 2

Please rate the all helpfull posts.
Regards,
Naidu.

[info]

Hello,

Thanks for your help, i come back to this just now, a few week later.

This is the config i made (some like ATM were already configured, i add VLAN 3) :

interface ATM0

no ip address

no ip redirects

no ip unreachables

no ip proxy-arp

ip flow ingress

no atm ilmi-keepalive

!

interface ATM0.1 point-to-point

description $ES_WAN$$FW_OUTSIDE$

no ip redirects

no ip unreachables

no ip proxy-arp

ip flow ingress

pvc 8/35

  pppoe-client dial-pool-number 1

!

!

interface FastEthernet0

!

interface FastEthernet1

switchport access vlan 2

!

interface FastEthernet2

!

interface FastEthernet3

description DSL via Belgacom BBox

switchport access vlan 3

!

interface Vlan1

description $ETH-SW-LAUNCH$$INTF-INFO-HWIC 4ESW$$ES_LAN$$FW_INSIDE$

ip address xxx.xxx.xxx.90 255.255.255.224

no ip redirects

no ip unreachables

no ip proxy-arp

ip flow ingress

ip nat inside

ip virtual-reassembly

zone-member security in-zone

ip tcp adjust-mss 1412

!

interface Vlan2

description $FW_INSIDE$

ip address xxx.xxx.xxx.60 255.255.255.224

no ip redirects

no ip unreachables

no ip proxy-arp

ip flow ingress

ip nat inside

ip virtual-reassembly

zone-member security in-zone

!

interface Vlan3

no ip address

no ip redirects

no ip unreachables

no ip proxy-arp

ip flow ingress

pppoe-client dial-pool-number 1

!

interface Dialer0

description $FW_OUTSIDE$

ip address negotiated

no ip redirects

no ip unreachables

no ip proxy-arp

ip mtu 1452

ip nbar protocol-discovery

ip flow ingress

ip nat outside

ip virtual-reassembly

zone-member security out-zone

encapsulation ppp

dialer pool 1

dialer-group 1

ppp authentication chap pap callin

ppp chap hostname xxxxxxxxx

ppp chap password xxxxxxxxx

ppp pap sent-username xxxxxxxxx

password xxxxxxxx

no cdp enable

So, i've tried to configure a WAN port on the Eth3 port and link to it an externat "Belgacom" adsl modem (i'll switch soon to VDSL2 that my cisco 877 do not support, so i need the external modem (BBox) used in "bridge" mode).

I created a Vlan 3 and set the Eth3 port to it. And it seems to work, i've internet access from machines on the others vlans.

But on the router, the CD led (carrier detect i suppose) is still flashing and the adsl interface tries to connect.

So i've disabled the ATM interface.

All seems correct for you ? I've a very little experience with routers.

Thanks

[paolo bevilacqua · Accepted solution]

You should have "mtu 1492", not "ip mtu" on the dialer interface.

And disable firewall, it's useless and slows you done.

Note it's possible that the 877 will not keep up with VDSL speeds.

[info]

Thakns,

1° So, I change on Dialer0 : mtu 1492 in stead of ip mtu 1452.

2° What speeds you think i can hope with vdsl with the 877 ?

[paolo bevilacqua · Accepted solution]

On vlan 1 and 2, mss adjust should be 1452.

Check attached document. Cisco now makes 880 router with VDSL interface, these would keep up.

Thanks for the nice rating and good luck!