Belkin Technical Support is Neither

[Note: this is the record of my attempts to get Belkin to fix a massive flaw in the design of their "routers."  The bottom line is that they refused to even acknowledge the flaw, and the result is that computers on the LAN side of a Belkin router can’t access servers on the LAN using the router’s public IP address or hostname.  Because of this, and Belkin’s refusal to acknowledge, let alone fix, the problem, I must strongly discourage anyone from purchasing a Belkin router.]

I can’t stand tech support.  It wouldn’t be so bad if they weren’t all thoroughly clueless, but they are.

Me:

Hello,

I just bought an F5D72304 router, and I’m having a problem with it.

I’ve got a few computers on the LAN-side of the router that are running services (http, ssh, etc).  From any computer on the internet outside of my LAN, I can access those services without problems.  But any computer inside my F5D72304’s LAN cannot access those services, whether on other systems in the LAN or on itself, through my public IP address.  If I use the computers’ LAN IPs then it works OK, but not if I use the public IP.

Let me use some numbers to make it more clear:

My public IP is x.y.1.194
Belkin router’s private LAN IP is 172.19.5.250
Computer lanbox-1 is IP 172.19.5.1
Computer lanbox-2 is IP 172.19.5.2
Computer lanbox-2 is running http on port 89
Computer remotebox is elsewhere on the internet

These connections work OK:

  remotebox -> x.y.1.194:89 (http over external IP)
  lanbox-1 -> 172.19.5.2:89 (http over internal IP)
  lanbox-2 -> 172.19.5.2:89 (http over internal IP)

But these connections do NOT work:

  lanbox-1 -> x.y.1.194:89 (http over external IP)
  lanbox-2 -> x.y.1.194:89 (http over external IP)

I’ve tried putting lanbox-2 (my http server) in the DMZ, but that didn’t change anything.  I’ve tried different ports than 89, still no success. I’ve looked around the router config but didn’t see anything that would fix this.  I have another router (an older D-Link model) configured exactly the same as the new Belkin (i.e. LAN is 172.19.5.* and forwarding port 89 to 172.19.5.2) and it doesn’t have this problem.

Please help!

Thanks,
Anthony DiSante

Them:

Hi Anthony,

Thank you for contacting Belkin Technical Support.

We understand that you are not able to access the services with the Wan IP from your network.

Anthony, There is a feature called NAT is present in the router. If you are trying to acess the router setup page from the external computer.  When the router see the WAN IP from the external network then it can perform natting that is it will change the public IP address of the external network computer in to  the prvate IP address range, which helps you to view the services. But with in the intenal network natting is not possible since the internal network already has the private IP address. That is why you are not able to use the wan IP to view the services in internal network.

Hope this information helps.

Regards,

[some person]
Belkin Technical Support.

Me:

Hello,

Thanks for your reply.

If I understand you correctly, you are saying that the behavior I am experiencing is the correct behavior?  You are saying that it’s correct that I cannot access services on my LAN from a system on my LAN using the public IP address?

If so, then that is a flaw in the design of your router.  I have used a half-dozen routers from various manufacturers and none of them exhibit this behavior.  When I use the router’s firewall to forward port X to box-2 on the LAN, that means "when a packet arrives at the WAN interface for port X, pass it through to box-2 on the LAN interface."  The source of the packet is irrelevant; all the router needs to know is that it arrived at the external interface, and that I’ve configured a firewall rule that explains how to handle that situation.

This is definitely worthy of a firmware upgrade, but in the meantime I’ll have to remove the F5D72304 from my network and put my old D-Link router in its place.

-Anthony DiSante

Them:

Hi Anthony,

Thank you for contacting Belkin Technical Support.

Anthony, we understand that you are not able to access services in your LAN using WAN IP address.

Belkin routers are enabled with NAT feature. This will not allow you to access the services locally by using the WAN IP address.

When you are trying to access the services from your LAN using the WAN IP address, the request goes upto the router then redirect the request internally in your LAN. The resolution happens in the router itself, hence the request doesnot go the internet and redirect to the router since it is a NAT enabled router.

The same thing happens with all the routers with NAT feature.

We hope this information is helpful. Please let us know if you require any further assistance. We’ll be glad to help you.

Regards,

[a different person]
Belkin Technical Support

Me:

Hello,

> Belkin routers are enabled with NAT feature.

So is every router I’ve ever used.  NAT is the whole point of using a router in a home network, since it allows you to have multiple computers on a private network connected to the public internet, with the router translating the addresses.  This feature is not unique to Belkin routers.

> This will not allow you to access the
> services locally by using the WAN IP
> address. ... The same thing happens with
> all the routers with NAT feature.

That is simply not true.  Every router I’ve ever used has allowed me to access services on my LAN via the WAN IP.  I have two other routers right next to me that I’ve been testing to make sure of it -- the Belkin is the only one that exhibits this error.

-Anthony DiSante

Me, again:

Hello,

> the request goes upto the router then
> redirect the request internally in your
> LAN.  The resolution happens in the router
> itself, hence the request doesnot go the
> internet and redirect to the router

That’s exactly the problem.  When a packet arrives at the WAN interface, it DOES "go [to] the internet" because the WAN IP is an internet IP.  So the router should treat it like any other packet arriving at the WAN interface; it doesn’t matter where the packet came from (LAN or remote system), what matters is that I sent it to the WAN interface.

-Anthony DiSante

ARGH.  How can you work tech support for a company’s router products and NOT KNOW WHAT A ROUTER IS SUPPOSED TO DO?

And it REALLY bugs me how a different person replies to the email every time when you email a company’s tech support.  Each successive person ostensibly reads the earlier conversation, but then just says the exact same thing.  That makes me so mad.  I emailed Dell a couple months ago, asking if I could get a laptop without Windows installed, and therefore without having to pay the $200 Microsoft tax. There were about ten -- TEN -- exchanges where I said "why is it Dell’s policy to force a particular operating system on the customer?" and the Dell rep said "it is Dell’s policy to force Windows XP on the customer" (essentially).  Each time it was a different person, each time I asked "WHY??!?", and each time the response just restated the fact that it IS the case without addressing WHY.

And as if ALL THAT weren’t enough, the tech support responses are always replete with typos and misspellings.