F2000 modem -> Cisco 2811

johnplayerblue

Hope this is an ok thread in which to ask my question. If not I apologize.

I'm using an ISP (Eircom) issued Huawei F2000 modem which really isn't a user friendly device. I could say a whole lot more but I won't as it isn't directly related to my question.

I've searched high and low for a client side config for to try and get an ethernet interface to work with Eir fiber/VDSL in much the same way as I used to with say traditional dsl.

I can get it working in bridge mode for both an ASA and the interface of the 2811. I have a 16 port switch module in the same 2811 and the SVI's can all pick up a public routable ip addres. This config is pretty cool but not what I want.

I can also get a simpler config working by just allowing say interface fa0/0 pick up a private dhcp address from the F2K which has more or less the same net result. Vlan's, SVI's, ASA ethernet and 2811 fa interfaces can all reach the outside world when NAT, routing and ACL's are configured.

However, the config I really want to get working would be akin to the old pppoe type template we'd have used on dsl connections.

The problem with the F2K - well one of the problems with the most unintuitive and just plain bad F2K is IPTV and WI-FI in bridged mode. For anyone who has travelled this laborious route you know the story.

And while the simple method of allowing the fastethernet0/0 interface on the 2811 pick up or even assign a private ip address and NAT the interface and all the usual stuff it isn't the configuration I want.

To be honest I'm not good at L2 or 3, 4... actually I'm not good at any layer but bba-groups and virtual-templates really aren't a strong point and so I'm well and trully stumped.

Although if anyone has sussed out how to get say Wi-Fi working on the F2K while in bridged mode I'd work with that. I don't watch tv so IPTV really isn't an issue. But if someone has a config that works all the better.

Hope I've made sense as I've really just typed as I thought about the config I want which isn't to say it'll be understood. Plus I do waffle on a bit so sorry about that.

ED E

My IOS knowledge isnt great so I cant fully answer you, but what I will say:

IPTV & PPPoE won't work, you're tunnelling past the stream source at the aggregator and terminating at the RAS.

Using Wifi on the F2000 while bridged doesnt really make sense, you'd be looping back from Public to Private and back. You could in theory do it with a pair of VLANs on the interface you're using for WAN but you'll never ever get that on a bulk retail home gateway device.

If you're going as far as to install a 2811 grab any old decent AP and use that.

johnplayerblue

Yea, even with my very limited knowledge I was at the point where I was starting to wonder if what I was trying to do was technically possible. The tv side of things isn't an issue or even a loss but would have been nice to try figure it out.

I've spent way too much time trying to get the wireless working in bridged mode and like you mentioned while it might be possible in theory I'd kind of settled on the fact I'd be using my old WRT or picking up a cheap enough HWIC-AP as I do have a slot to spare.

I was kind of hoping for a IPoE config that might work but after much trial and error I thought I'd finally just ask someone and see if what I was trying to do was actually even possible as it is IPoE. That said, I do have an old ZyXEL F1K which I seem to remember was slow as hell to navigate but had some decent L2 options.

But with the configurations I describe previous I can't complain as I'm getting full speed. Latency and jitter are perfect and I guess I became way too focused on trying to get my original idea working.

Thanks by the way for your technical insight.

Tell you what - I'll trade you my IOS "knowledge" for your engineering skills. Think I'll stick to the LAN side of things for now. At least there things are technically possible ..mostly.

mass_debater

IPoE is basically DHCP, have you tried using DHCP client on the WAN interface of your router, it might work. You'll need to set the VLAN identifier to 10.


I've been meaning to try this myself btw

johnplayerblue

Yea tried that. Tried a router on a stick type config on the 2811. Created a sub interface with vlan 10 along with various configs I'd found here and there. The debugs showed the router going through various stages of connecting but came to nothing.



It would appear that a bridge or a simple:

int fa0/0
ip add dhcp
no sh

and a nat config is the simplest way.

The only good thing about the F2000 modem is the placement of on/off button and how quick it is to navigate about which is just as well as you never know where you'll find a feature. But in the case of the F2000 modem the feature won't be there to beging with.

I mean I can't even ssh or telnet into this thing. Can't set a static route. You get rip or even rip v2 if you want it ...

I won't go on. A terrible terrible router. Fantastic for what it was designed for but no more.

Packet

Here's a little detail to explain what's going on with F2000 when bridging. A little theory makes getting it working a lot easier.

When the WAN interface connection type has been set to "Bridged" the F2000 will bridge Ethertype frames for PPPoE, IPv4, and IPv6.
But misconfigurations/states that prevent you successfully setting up an Internet connection through the F2000 can happen.

The Ethernet frames sent out the WAN interface must be tagged with VLAN ID 10. The F2000 WAN interface can be left doing this. Only do this in one place, don't also tag them on the inside router.

IPv4oE, IPv6oE, and PPPoE are different cases so I'll go through each of them.

For IPv4oE your router will be sending out a DHCPv4oE discovery packet that needs to be bridged out the F2000 WAN interface. What can go wrong here is the DHCP server in the F2000 is still active and it responds instead of eir's DHCP server. To avoid this make sure Home Network->LAN Interface->DHCP Server is disabled. The F2000 will retain its IPv4 address shown under LAN Interface Settings and the F2000 webgui can be reached using this address as long as you statically configure an IPv4 address from the same 192.168.1.0/24 prefix on the device debing used to access the webgui. Webgui access to the F2000 can be lost if the device you're using picks up a public IPv4 address. To get access back you have to statically set its address.

IPv6oE is similar to the above case except you need to 1) Ensure that RA Settings->Enable RA is not ticked. 2) Ensure that IPv6 DHCP server is not ticked. These must both be disabled so that you receive the RA from the eir BNG router and so that the only DHCPv6 response is the DHCPv6-PD from eir's DHCPv6 server.

PPPoE can't be used if you've got IPTV because PPPoE frames are bridged straight through the open eir DSLAM or OLT preventing them doing multicast replication of the TV station onto your line. PPPoE MTU is restricted to 1492 bytes. PPPoE is only used with static IPv4s.

johnplayerblue

Packet wrote: »

A little theory makes getting it working a lot easier.

Something of an understatement

I don't work in I.T but do love networks and would love to spend the rest of my working life working with networks. For this reason I smiled when I read the above. Networks and networkins is what? 90% troubleshooting?! in order to troubleshoot you need two things. Experience and tons of it. And the theory of how a particular technology works or should work as the case may be.

On the LAN side that isn't such a problem. But once you leave the demarc it can be hard to visualize just what is happening at the other end.

In such a situation all you have is the theory and some very helpful explanations from yourself and and the likes of ED E who sounds like he/she has forgotten more than I'll ever know. But this is why I love networks. You just never stop learning and it keeps you very humble which is just as well as sometimes you have to ask some really naff questions but asking questions is how we learn - well that and breaking stuff.