Virtualisation is a great technology for maximising system utilisation and increasing workload flexibility, but it does have its problems. We will look here at the five biggest issues with virtualisation and how they can be effectively tackled with simple business policies. No IT services system is perfect, but companies can avoid burdening their administrators and wasting resources by understanding these problems and using these tips.
1. Virtual Machine Sprawl – this happens when a company adopts virtualisation slowly, requiring administrators to keep adding servers when the initial setups become overloaded. Before Virtual Machine (VM) technology became mainstream, adding a server and loading even a single workload was a big deal that took a lot of time and effort. Naturally, the process was taken seriously. Now, because it takes all of a quarter hour to get a few new servers loaded with VM to handle a hundred workloads, proper deployment is sometimes overlooked. To avoid wasting valuable computing resources, companies need not limit virtualisation but simply set up the proper policies that go along with managing VMs. Checking if their use is being maximised can maximise computing power and save backup and recovery resources.
2. Network Traffic Congestion – this can be caused by several VMs on a single server because of the network bandwidth that they require. Most servers used in virtualisation have only one network interface card (NIC) port because in the past most servers only housed a few applications. So, network congestion can happen even when there is enough memory and CPU cores for several VMs. To prevent errors and crashing among workloads, companies need to upgrade to gigabit Ethernet ports and add multiple NIC ports. Since the process is so simple, rebalancing workloads in the meantime is also a feasible solution.
3. Consolidation and Server Hardware Failure – Consolidating VMs on fewer servers can decrease costs and IT systems maintenance headaches, but going too far can cause even bigger problems with the hardware that supports your virtualisation efforts. There are live migration tools and snapshots that aid administrators in keeping VMs and their workloads functioning properly. But when a server gets overloaded with so many active workloads, server failure is imminent. Again, traditional physical servers were not made to support so many applications at once. Your IT systems may have adequate fail over functions that can restart affected workloads on other servers from snapshots, but there is still downtime to consider. This can become significant if the images are large and the network is congested. Limiting the number of running workloads on a server and redistributing them to other servers as well as planning for high-availability servers will prevent hardware issues like fatal errors.