I'm looking to re do a few things in our data center soon. I plan to buy a second 4506 so i can run GLBP. Currently i have one 4506 doing all of my intervlan routing with numerous layer 2 switches connected to it as well as all of my servers. I would like to add a second link from the servers to a new 4506. I would like to do the same for most of the switches where i have spare fiber links. My question is since i have about 30 SVI's on the 4506 and if i add another 4506, what kind of links do i use to connect to the layer 2 switches? Right now they are layer 2 trunks and if i have 2 links going from one switch to two 4506's, STP will put one in blocking which seems like it would not allow GLBP to function correctly. any suggestions?