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Dustin23Flag for United States of America

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Cannot ping laptop from domain controller

I have a laptop that I added to my domain while attached to the LAN.  I then  disconnected from the LAN and connected to my wireless network, which is on a different subnet.  The wireless router is configured to use the same local DNS server as my LAN domain, and I can ping any of my servers from the laptop by using the NetBIOS name.  When I try to ping the laptop from any of my servers using the NetBIOS name, the name is resolved to the correct address but the ping itself is unsuccessful.  ICMP-In requests are open on both ends for the domain.  Any ideas on why this may be happening??
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AriMc
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gbarrientos

Try disabling the firewall
Right off the bat check the following things:

1.) Be sure default gateway is properly configured.
2.) If DHCP is used, be sure the address(s) are being appropriately leased and working, along with default gateway configuration on the scopes.

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@ AriMC

Yes this has already been done.
@ gbarrientos

I just tried this, and I still have the same result.  The laptop's NB name is resolved to the correct address during ping, but ping is unsuccessful.
@ larrylarrymusic

1) How can I do this?  On the wireless network the default gateway must be configured to be the host address of the router itself.
2) The addresses appear to be working fine for the network.  Leases set to expire in 24 hours.
Could you provide the actual IP-addesses, netmasks and default gateway addresses for both the server and the laptop?

what if you use traceroute instead of ping ?
Can you see some of the ICMP packets ?

Can the laptop ping its router?
Can it ping some node in its own subnet? In another subnet of yours? On the Internet?

@vivigatt

It seems now that the problem is that the server cannot ping the wireless router.  I am going to change a setting and see if it works.
Ok, so I just ran a trace route on my wireless router's LAN address (192.168.1.50) and the address resolved to the NetBIOS name of the laptop on the wireless network (10.200.40.3).  Seems really strange.  Once again, when I start a ping on the laptop (10.200.40.3) from one of my servers using the NB name, it resolves to the correct address but the ping fails.  So it seems the trace can't handle the shift on the wireless router from LAN address (192.168.1.50) to WLAN address (10.200.40.1).  Subnets are /24 (LAN) and /28 (WLAN).  This help anyone?
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gbarrientos

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@gbarrientos

Ok I will do that then.  I thought there was a way to get the other way to work.
No because the router acts like a firewall and it does NAT. So traffic will flow fine out but coming back in will be blocked.
gbarrientos is 100% right.
The only way around would be to use you router as a real router, not a NAT, if it can do that. DD-WRT firmware can do this on various devices, but this makes the configuration much more complex and having the wireless lan in the same subnet as the rest of the LAN makes things much easier.
Just don't use the "Internet" port on your wireless "router" (which will then be used as a wireless access point only).