I have a network with 4 VLANS. The switches are 2980s and 3640 router routing my VLANS. When a user accesses a server on his same subnet all is good. However, when a user from a different VLAN from the server accesses the same file it is all very slow. The router is setup with an 802.1q trunk (100Mb) to the switches. The routers CPU load is very low.
How do I trouble shoot this issue?