Broadcast across subnets/routers 2

[davekeene]

Have just split the network up so the wireless lan is on a different subnet. Now have all the usual problems associated with NetBios naming.

Is there a way I can make the wireless router pass broadcast messages between the subnets and so avoid having to change over to Wins/DNS (as most of our IP's are dynamic?).

Currently the router is set to "both directions" and RIP-2B. There are settings for RIP-1, and RIP-2M that supposedly allows multicast, but I'm not sure if that will help or hinder.

TIA, DK

 

[bcastner]

Unless you have a Windows server class product, WINS or DNS is unavilable to you except through third-party products. DNS can easily handle dynamic IPs through dynamic registration though.

You want to create a LMHOSTS file and distribute it to all clients:

http://support.microsoft.com/?kbid=101927

http://support.microsoft.com/defaul...port/kb/articles/q150/8/00.asp&NoWebContent=1

http://support.microsoft.com/?kbid=314108

 

[chieftan999]

From a routing perspective you need to have broadcast forwarding and helper addresses configured.

Go to the Cisco site for examples of configuration.

 

[Serbtastic]

An LMHOSTS file will only be useful if the client IPs are static. In a DHCP environment, where client IPs are dynamic, the lmhosts file mappings will quickly become inaccurate.

 

[rcraig12]

We have no idea of the software he is running over his LAN's.

Oh and what kind of devices he is using to segment his network.

Please more info!

 

[davekeene]

Thanks for the replies ... extra info is as follows.

1) We are running various windows servers and PC's. Our unix and macs are minimal and not relevant to this discussion.

2) We're using netgear stuff mostly FR328S routers. The WAP Routers (which are the one we want to broadcast through) are netgear WGT624 and supports RIP multicast and broadcast.

3) LMHOSTS won't work because all the segments are DHCP allocated (from the routers)

4) WINS works in that you can get to any computer you know the name of, but doesn't show the computers in the browse list unless we put a browse master on the subnet (as a backup domain controller I believe) which is another wasted box and more to maintain.

5) DNS (I think) is even more trouble because I have to make the DHCP servers register their allocations with the DNS server and I only know how to do that if the DHCP server is a service on an Windows box, rather than in the router.

Any more help gratefully received

Ta,

 

[bcastner]

. There is no resolution possible under your Negrear equipment other than using LMHOSTS with static IPs. Member Serbtastic criticized this solution, but as long as you use your router DHCP servers for a Windows name resolution issues accross subnets, there is no other solution. Note: Serbtastic criticized, but offered not other possibility.

Do not use your residential routers as DHCP servers in your setting. Do not expect a residential router to resolve subnet broadcast issues.

This is a Windows Name resolution issue, so use the tools you have to handle this issue.

. First, are you sure you need the subnets?
. Second, Windows server DNS would handle this easily. Without broadcasts.
. There is no way you will be ever happy in a Windows Win2k or above server setting without properly using DNS. For Win2k or XP clients, you will be decidedly unhappy unless you buy the DNS name resolution model. See: faq779-4017

 

[davekeene]

Thanks for that.

Just as an aside, LMHOSTS doesn't give me browse lists and WINS resolution does work without the overhead of distributing files...

As to your questions/hints:

Do we need subnets? Well, I don't want them but I don't see how to do without them - it may just be that I should have bought firewalls, not firewall routers and that is my real problem. We have put our servers into a corporate cell, firewalled on one side to the internet, firewalled to the desktop PC's on the other side. The wireless lan is configured as a subnet of the normal lan just to get another firewall between the laptops (of visitors) and our other desktops just in case anyone manages to connect to the W-LAN "accidentally". Also wanted to give the wireless machines access to our inner (office) net and not to the corporate servers and thought it would be easier to exclude everyone on a subnet - think I may be off here, since they'll all show with the WAN-side IP of the router rather than the local IP anyway.

As for DNS, I think that is the way we'll have to go - was reluctant because of having to configure all the machines with a fixed ip for the DNS server (doh, should have remembered I can do that through DHCP anyway).

If you know of a better way to do what I want, without buying more equipment - I'd be interested. (Even if that involves telling me I'm and idiot and going about it completely the wrong way)

TA

 

[bcastner]

As for DNS, I think that is the way we'll have to go - was reluctant because of having to configure all the machines with a fixed ip for the DNS server."

No you do not. Your Windows DNS server, and your Windows clients support dynamic registration of their addresses.

 

[chieftan999]

bcastner is correct.

DDNS - Dynamic - Win 2 K +

 

[davekeene]

Thanks again .... as a small aside (see, you shouldn't be so helpful) will this also resolve the issue of finding a PDC/BDC on a different subnet to the one the client is on.

At the moment it's saying a domain controller can't be found, but re-establishes all the shares ok anyway.

Ta (again)

 

[bcastner]

Yes.

You make the Trust relationship between the PDC and all BDCs. This ensures that the tables are duplicated.

 

[davekeene]

Erm, not the problem I was thinking of.

There is no PDC/BDC on the wireless subnet (10.0.2.*) only on the office subnet (10.0.0.*).

When I logon on the wireless subnet it tries to find a DC by broadcast which obviously doesn't propogate to the other subnet.

I know you can fix this with an LMHOSTS #PRE #DOM entry, but was not sure if your DNS solution would automatically resolve it for me.

Ta

 

[chieftan999]

Do you have broadcast forwarding enabled on your Layer 3 device?