 these designs is that there is no easy way to manage the servers remotely. If you have easy access to the servers, having a Keyboard Video Monitor (KVM) switch in each rack can solve this problem. However, e-commerce web sites are typically hosted in separate collocation facilities. In this case, remote management capabilities are vital. Remote management is often accomplished with another VLAN that connects to every server and network device at the site. This management VLAN then connects to a router or firewall that allows connectivity to the main site. Figure 33-15 shows such a design. You've gone through great pains to make sure the servers are secure. You've separated all of the servers into layers, and prohibited the web servers from commu- nicating with the database servers. Now, you've added another VLAN that connects them all together. If you're thinking that this looks like a bad idea, you're right. The benefits of a management network do outweigh the risks, but only if you design the network properly. Chapter 33: Designing Networks Internet Web VLAN Upper application VLAN Lower application VLAN Upper database VLAN To management networks Lower database VLAN Management VLAN Figure 33-15. E-commerce management network Management networks should be very secure. Features like port security and private VLANs can help keep the network secure. No server should be allowed to talk to any other server on this network, with the exception of backup and telemetry servers. The problem with all these VLANs is that they are usually combined with a high- availability network design. For every VLAN a server must connect to, it must use two Ethernet interfaces: one for each of the switches in the high-availability pair. While this may not sound like a big deal, with only three VLANs for the average server, that's six Ethernet interfaces in use. Figure 33-16 shows a typical server connected to three VLANs on two switches. Switch 1 Switch 2 Trunk Upper layer Upper layer Lower layer Lower layer Server Mgmt VLAN Mgmt VLAN Fi