IP addresses help devices stay connected to the network. Non-availability of an IP address means that a device loses some or all of its ability to access or use the network. The severity of the issue depends on what that device is, i.e. a laptop, PC, or a critical server. DHCP servers play a vital role because they automatically assign IP addresses to devices whenever they enter a network. DNS servers on the other hand provide network clients with the service of domain name resolution.


Any problem hindering operation of these servers, be it performance, availability or scalability, impacts productivity of users. So, what are the factors you should consider when selecting DHCP/DNS services for your network?

  • As an organization grows, so too does the number of devices and the need for IP addresses. High performing DHCP and DNS servers are required to meet the growing IP requests of the network. Sometimes, a single DHCP server may no longer be sufficient, meaning more servers to service IP requests may be required. This means more administration and configuration tasks for the administrator.
  • Given the importance of the DHCP server being available at all times, it’s advisable that the DHCP service run on a dedicated server that is unlikely to be affected by other services that consume hardware resources and impact server performance.
  • Most importantly, ensure high availability and increase fault tolerance with redundancy options. This means additional investments, and we all know that services from Microsoft® and Cisco® are expensive. Moreover, investments made on additional licenses for redundancy fall heavy on allocated budgets.
  • At any given time, the administrator needs to quickly know the availability of an IP address, the utilization status of all DHCP scopes, and subnets in the entire IP space.

Microsoft and Cisco are the common DHCP/DNS vendors servicing IP distribution needs in an organization. But, there are also Open Source solutions like the one from ISC (Internet Systems Consortium) Inc. that has a fair share of the market. These services are suitable for use in high-volume and high-reliability environments. In fact, ISC BIND DNS is the reference implementation for every other DNS service today and is widely used by many enterprises. DHCP/DNS solutions from ISC can be downloaded and installed free of cost as compared to other vendors, especially those from Microsoft, Cisco, and other appliance based solutions.

Cost-effective solutions easily stand atop other vendors on license and maintenance costs, community support, and global audience. ISC DHCP and BIND are built around standards, hence are used by most admins, operating distributions, and are integrated into solutions by vendors. Even if you’re currently running your DHCP services on Microsoft or Cisco, you can consider ISC for an affordable failover option that gives you precious time to get the partner server up. However, an important point to be noted is that it’s all CLI (Command Line Interface) based, meaning you’d have to be quite handy with command line configurations. This problem can be overcome with tools that provide convenient integration, including support for ISC DHC. This way you can eliminate frequent use of CLI and don’t have to worry about skilled resources to handle complicated configurations.

Every DHCP and/or DNS outage costs in terms of decreased productivity, increased expenses, and lost revenue. The risk caused by not having a reliable DHCP and DNS deployment seriously impacts your business and reputation. Administrators nowadays are looking at options that help consolidate management of multiple vendors under one platform. The addition of any number of DHCP/DNS servers from different vendors should not disrupt existing management processes.

As we can now see, ISC is a viable solution for DHCP and DNS because it gives the user highly available, reliable, high performing, and scalable services without massive upfront hardware appliance or license costs and recurring maintenance charges.