ping does a lookup but returns IP from different VLAN

[HMCTech]

We are trying to eventually get apple's active in our windows enviroment and have only been able to bind so far, cannot do any AD users logins.

 

One problem we have is if we do an nslookup on a server it returns all the IP's for that server on all our tagged VLANS. The problem is that when you ping a server on the mac it returns an IP address that is on a different VLAN to the mac, for example if we ping our DC it should be on a 10.1 address but it returns and tries to ping a 10.3 address.

 

Any suggestions?

[Geoff]

Why is your router not routing the traffic?

[HMCTech]

Sorry?

[Geoff]

If you try and access something thats not on your local subnet, then it should route via your default gateway to get to it. Why doesn't that work?

[HMCTech]

Oh, well because we use tagged VLAN's. We have not subnetted anything.

[SYNACK]

I may be missing something crucial here but unless tagged vlans implement routing automaticlly I don't get how your network is working.

 

A VLAN forms a layer 2 (switching) domain, traversing between them requires a device on multiple vlans like a switch configured as a router or a server. If it is not subnetted there is no benifit in using vlans as there is no actual segmentation just a bottleneck as everything including the broadcasts flow through the server.

 

I would suggest that you do an ipconfig /all on several machines in different vlans and see what the ip settings are just to make sure and provide some clues on how the traffic is actually flowing.

 

If it is setup currently in a way that allows packets to leak from ome vlan to another that could be a reason that the name lookup is returning a different value than expected.

[nicklec]

What subnet mask are you using? Sounds like your using VLANs between two subnet that couldn't normally communicate? Edited June 29, 2009 by nicklec

[K.C.Leblanc]

Sounds like a stray DNS entry.