What are three important reasons to create a server cluster within a virtual environment?
Creating a server cluster within a virtual environment is important for several reasons. The first reason and arguably the most important reason is for redundancy for your VMs. This redundancy comes from having multiple hosts within your cluster that your VMs can fail over to in the case of a host failure. Combining host clustering with the High Availability utility allows you to reduce the possibility of downtime within your environment. A second reason is for balancing the workload between your hosts so one host does not become overly burdened with the resource requirements of the VMs all the hosts in the cluster can share the workload by placing VMs on different hosts throughout the cluster. Finally creating a cluster allows for easy addition of resources into the environment with no downtime. Simply add a new host install the version of ESXi you are running and then add it to the environment. This will allow you to add resources without the need of taking a host down and creating downtime.
What is DRS and why would you want to enable it within your host cluster (VMware)
DRS or the Distributed Resource Scheduler is a utility that balances resources within a virtualized environment. You would want to enable the utility within your host cluster as it will help automate balancing the workload and your VMs within your environment, a simple but effective example is placing 2 large resource heavy VMs on host 1 and placing 5 smaller not quite as resource intensive VMs on host 2 to keep the workload balanced between hosts. Because the Scheduler can be fully automated it can place new VMs in the cluster where it will be most efficient and move current VMs to other hosts as needed.
What is DHCP and how does it fit into a large-scale business?
DHCP (Dynamic Host Configuration Protocol) allows for the automatic distribution of a selected range of IP addresses across a designated network. It is usually a requirement for large-scale businesses to use DHCP in their environment as this allows clients connected to the network to receive a dynamic IP address that is handed out by the DHCP server. Thus eliminating the task of needing to go through and assign a static IP address to each client on the network.