Not sure if this is a spanning-tree or vtp domain question, but wanted some input regarding our campus. We have approx. 100 access layer switches, mostly 2900xl, and 3500 xl switches throughout 5 buildings all interconnected via fiber. We have 2 6500 core switches running sup 720 running hsrp between them. We have approx. 30 vlans and 1 vtp domain. I have been advised by a consultant that I should probably break up my network by adding some Layer 3 routed links between at least one of the buildings to make up couple of smaller vtp domains. Wanted to get some feedback here on this suggestion, and understand why this would be necessary. We recently did have a strange network problem where we lost access from all vlans to our server vlan because of a possible network loop somewhere, and as a result of this issue, that recommendation was made. Please let me know what you think.