04-23-2015 07:02 AM - edited 03-07-2019 11:42 PM
I have a 3750 switch with two 48-port switches connected via stacking cable. On these switches I have two VLANS: VLAN100 for data, and VLAN300 for Desktop VTCs (dVTCs). I configured the switch with VLAN 100 having an ip address.
I have verified:
-IP Routing is enabled
-the default gateway is correct
-my trunk port is dot1q encapsulated and passing VLANS 100 & 300.
-On my Cisco 2951 router, I have created sub-interfaces with IPs and dot1q encapsulation.
-I am running OSPF and verified that both my data and video networks are being advertised.
Here's the problem: When I move my dVTCs into VLAN 300, I cannot ping the devices from either the switch or the router. I am able to ping the VLAN 300 gateway from the switch, but I am not able to ping either of my dVTCs. Also, from my dVTCs, I cannot reach the gatekeeper. The interesting thing is that when I move my two dVTCs into VLAN 100 and move the VLAN 300 sub-interface address to the VLAN 100 sub-interface as a secondary address, everything works great on my dVTCs.
I have other campuses where I run the same configuration of VLANs, and everything works great. I feel like I am just missing something on my switch that I missed in my configuration but I am not seeing it. I apologize, but I am not able to post my configuration as my network is an isolated DoD network and cannot be posted. But if you have some ideas for me to check, I would appreciated it.
04-23-2015 09:12 AM
When you move your dvtcs to vlan 300, do you see the mac addresses in that vlan?
sh mac address-table vlan 300
Also, on the router, do you see the IP address of the dvtcs?
sh ip arp <the ip address of the dvtc>
HTH
04-23-2015 10:14 AM
When I move my dvtcs into vlan 300, the dvtc mac address do not show up in that vlan. Also, when I sh ip arp, I show the two dvtcs addresses in vlan 100, not vlan 300. Under the sh ip arp, I see the dvtcs gateway in vlan 300 (in this configuration, I can ping the gateway from the switch, but I cannot ping the device IPs)
When I move my dvtcs into vlan 100, both dvtc mac address do show up in vlan 100. In the sh ip arp, I show the two dvtcs and the dvctc gateway in vlan 100 ( everything works)
04-23-2015 10:25 AM
For test, can you try creating a completely new vlan (vlan 50) and put the dvtcs in it and test again?
HTH
04-23-2015 10:47 AM
I created VLAN 400 and placed the dvtcs in that vlan. When I showed the mac address table, I showed both dvtcs in VLAN 400. On the router, I created the new sub-interface for VLAN 400 and move the dvtc gateway there. When I showed the arp table, I showed the dvtc gateway in both VLAN 100 and 400 and both dvtcs were still in VLAN 100
04-23-2015 11:32 AM
As a follow-up, I did a clear arp on my router and now the two dvtcs do not appear in the arp table. I do show the gateway address showing VLAN 400.
04-23-2015 11:46 AM
I was just about to post for you to clear the arp.
So, it is working now?
04-23-2015 12:05 PM
I am not able to ping the dvtcs.
I do see the gateway address showing in VLAN 400.
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