I ran into the issue with web-based application is not working on PCs in 2 of my VLANs. I have network with 2 "core" switches: 1x 4006 and 1x4506. There's router "on the stick" config for VLAN routing for all of the VLANs, but 2 I'm having problems with. Traffic from these 2 is routed by 4506 switch, using it's layer 3 switching capability. I tested the application on PCs in different VLANs and had no issues, except 2 VLANs which are beeing routed by 4506 switch. I'm not sure why the app is working in VLANs routed thru "VLAN router", but not while the traffic is routed by 4506 switch...
I'd really appreciate any suggestions.