Cisco 887VA Fibre configuration

[campbellkay001]

Hi Guys,

we currently have a Cisco 887VA (MPC8300)

Just wondering if i can configure a fiber connection on this device, struggling to find a configuration. 

Fiber is on vlan 10 connected directly to one of the FastEthernet ports, i thought i would create a virtual interface in the same way as you would for VDSL, but it doesn't let you, im guesisng because the FastEthernet ports are layer 2.

does anyone know how to do this.

i basically need a virtual vlan 10 interface with a PPPoE dialer configured.

any help much appreciated.

Thanks

[Mark Mc Nicholas]

Hey,

Ok so i've done some testing and this should work however I can't say how good the performance will be, I suspect Not very good.

I have not included the glue needed to get NAT working I'm assuming you can work that out if not let me know. I have assumed your ISP modem is in bridge mode and not de-tagging the traffic (Check that) and is plugged into interface fa0

vlan 10 
name isp

interface fa0
 switchport mode trunk
 switchport trunk allowed vlan add 10

interface vlan 10
 no ip address
 pppoe-client dial-pool-number 1

interface Dialer1
 ip address negotiated
 no ip redirects
 no ip proxy-arp
 ip mtu 1452

ip tcp adjust-mss 1412

 encapsulation ppp
 dialer pool 1
 ppp chap hostname <pppoeusername>
 ppp chap password 0 <pppoePassword>
 ppp ipcp route default
 ip nat inside

It works by letting the Dialer interface get the isp via the SVI, It's an ugly way of doing it but it got my lab router online when I tested it 

I hope this helps

[campbellkay001]

Thank you Mark will test this out this afternoon and let you know if this works. 

Looks hopeful though, yeah i can sort out the NAT side of it.

[campbellkay001]

Managed to get this all working.

Only thing i really had to change was the MTU settings, the dialer keep dropping its connections

added these two lines in

 ip mtu 1452

ip tcp adjust-mss 1412

seem to sort it out, thanks for your help

[Mark Mc Nicholas]

Hi,

I'm glad to help, It appears your provider uses a smaller MTU then the one I tested with sorry about that,

I've edited my post to include your corrections to help anyone who looks at it in the future.

I'm wondering what is the performance like as this is not really how the router is designed to be used, So  i'm wondering is CEF still happy? what kind of speed are you getting download & upload though this configuration?

Thanks

Mark

[campbellkay001]

Hi,

I was getting 50Mbps up and down, the fibre is contended so it could vary, when I tested it directly from the ISP modem, I was getting 90Mbps up and down, although this was a few days ago.

Generally fine for my client requirements at this point.  would of thought these devices would have a true WAN port.

Thanks,