Hi,

I just held a LAN party last weekend, and we had an issue where it wasn't possible to connect to the LAN only LFS server. When you specified the IP, it would say it is invalid.

After some trial and error it seems there's a bug (maybe feature) that only allows LAN servers on the RFC1918 Private IP Address Ranges. We did get a few to connect but it turned out to be too much trouble to reconfigure equipment and get people to change/renew addresses mid party.

Scawen can you confirm if this is a bug or deliberate?

I guess this could be a feature, but it's not conventional. Are internet games with no-master a no-no? I don't know of other games with this limitation.

Is it possible to have a private LAN server (no master) on a routeable IP?

Rob

Yes, this is intentional.

It's a protection thing, to stop people with illegally unlocked versions going online. If people want to go online invisibly, they can use a hidden host.

But we always wanted to allow people to be able to use LFS on a LAN, as our license allows you to unlock two copies so you can race a friend on a LAN. We also wanted to allow LAN parties which are not connected to the internet. So we do allow direct connection, using the IP ranges that are specially reserved for local networks.

Thanks for the response Scawen... Hope your enjoying the break from code cutting.

Back on topic...

I'm not convinced that strategy is really sound to defeat illegal use. It's trivial to defeat. It would make more sense to only allow connections within the same subnet surely (as most games do now days). It would also allow for a LAN type game browser.

Using the Subnet method, any addressing scheme can be used, not just assuming all LAN' use the RFC1918.

Is this something you would consider changing?

Rob

We also had that problem at a lan party..It's true that allowing it on subnets would be a good thing

What reason is there, for people not wanting to use the private network ranges, when they set up a private network?

I don't have great knowledge of setting up networks - I've only set up my home one. But with my limited knowledge, if I was setting up a LAN, I would go with the default ranges, set aside for local networks - it just seems the sensible thing to do.

It also seems to be the default action by the few routers I have seen.

Quote from Scawen :

What reason is there, for people not wanting to use the private network ranges, when they set up a private network?

Windows. If you have DHCP enabled Windows doesn't let you assign an additional private ip to the network card, so all the computers in the LAN will need to use the 'global' IP's to communicate. I used to have to do this, though now I have an extra network card (a pretty crappy solution to such an idiotic MS design problem) in my Windows system for LAN.

Even with DHCP enabled, the DHCP server just hands out IP's in the range of IP's specified, which can easily be set to 192.168.X.X, and TBH I can't see any reason why anyone would set up there router/DHCP server or machine to use a non-private network IP range, there is just no valid reason I can think of.

Dan,

Quote from danowat :

TBH I can't see any reason why anyone would set up there router/DHCP server or machine to use a non-private network IP range, there is just no valid reason I can think of.

Because private IP's dont get routed to the internet And I cant control the DHCP server, since it is at my ISP's end. From there my systems get a global ip address (212.149.x.x) and when I use this in Windows I cant use anything else at the same time without an extra network card.

But the guy was using a LAN, not a WAN, that and the fact it is possible to assign more than one IP address to a NIC (maybe a pro only feature) still makes it wierd why anyone trying to run LFS on a LAN would encouter problems.

Dan,

Quote from danowat :

But the guy was using a LAN, not a WAN, that and the fact it is possible to assign more than one IP address to a NIC (maybe a pro only feature) still makes it wierd why anyone trying to run LFS on a LAN would encouter problems.

My reply was to Scawen's question... And yes it is possible to assign more than one IP address to a NIC but not in Windows (if you have DHCP enabled). And LFS wouldn't work on my LAN(Not that I personally would really need it to either) if I wouldn't have the extra network card because I would need to use the global ip's and LFS doesn't let me do that.

What is wrong with this: your router gets its external IP from your ISP's DHCP server and assigns private IP addresses to the entire LAN (and depending on the router you can manage subnets and VLANs) from the IP pool you define. Logically this pool would consist of private IPs (10.* or 192.168.*).

If someone needs to connect to this LAN fom the outside in order to participate in the LAN, create a VPN connection on the same IP range and subnet. The router will probably need to support IPsec passthrough or some other trickery to get it connected but surely it is possible?

Quote from NotAnIllusion :

What is wrong with this: your router gets its external IP from your ISP's DHCP server and assigns private IP addresses to the entire LAN (and depending on the router you can manage subnets and VLANs) from the IP pool you define. Logically this pool would consist of private IPs (10.* or 192.168.*).

Many things:
- The systems would need to use NAT to access the internet (which is an ugly hack and shouldn't even exist), and thus they would not have global IP addresses anymore which would mean quite many complications.
- My ADSL router is in bridged mode, and the configuration is turned off from the LAN side so only my ISP could change it.
- It would be a pretty crappy solution to get one game working, having to re-order your whole network?

And, again, I dont need to get LFS working on such a setup, Scawen just asked why someone would not use private ip's for a private network, and it is not that uncommon. The school I was in some years ago also had a system like this where all the computers had a global ip address. When they are on the same subnet they work on the LAN fine, NAT is not something you should be forced to use, it is just an ugly solution to an ugly problem. An assumption that computers on a LAN always use a private IP is wrong, plain and simple.

Ah guess it's a problem for your network then For LAN parties though that happen to use NAT perhaps still an option even if it's a dirty hack?

Quote from NotAnIllusion :

Ah guess it's a problem for your network then For LAN parties though that happen to use NAT perhaps still an option even if it's a dirty hack?

No, it isn't, since I have the extra network card for LAN For LAN parties using private ip's propably are not a problem, unless you have your LAN party at somewhere where you cannot change the infrastructure. Like I could imagine if we had kept a LAN party at my old school; "Can we have a weekend at the auditorium for a LAN party?" - "Sure you can, just dont break anything." - "Cool, now can we re-configure the whole school network so we can play LFS?"

Hehe, I never asked permission for that so it wasn't an issue But I get what you're saying

Someone explain to me why NAT is an ugly hack to an ugly problem?

Quote from TagForce :

Someone explain to me why NAT is an ugly hack to an ugly problem?

Wikipedia.

Unfortunately there arent enough IP's in the world to avoid it. That is, until we get IPv6.