In my environment we recently installed some Dell 4148-on core switches, they will be running OSPF however the routers and ASA's are running BGP and EGRP. What do I have to look out for and is there any configuration on the routers and ASA's I may need to do?
If the Dell support OSPF, if you looking to have IGP in place in the network. Configure Router/ASA with OSPF and redistribute the network in to EIGRP/BGP.
there are many possibilities and limitations are available in your case. I am not aware of your switch as License and software version etc.
Solution1: Redistribution from EIGRP to OSPF but it will increase an admin headache.
Solution 2: Migrate from EIGRP to OSPF routing. It requires redesign and reconfiguration of your network. A testing and downtime windows of course.