On-Device Configuration Management Helps Meet New Networking Challenges
By Tomas Mellgren, Tail-f Systems
Configuring today’s networking equipment has become increasingly complex, driven by sophisticated value-added services, faster time-to-market expectations, and greater demands for network performance and reliability.
NETCONF and YANG are important new technologies and standards developed to address these challenges. Together, they provide a powerful alternative to costly and error-prone command line interface (CLI) scripting for automated configuration management. They are both more flexible and easier to use.
NETCONF is an IETF standard that defines the data encoding and protocol messages exchanged between a manager and an agent. YANG is a data modeling language designed to complement NETCONF. Standards groups such as MEF (formerly Metro Ethernet Forum) are adopting YANG as a device configuration standard, and the IETF through the NETMOD working group is moving to standardize the language.
NETCONF includes robust features to ensure that configuration changes occur consistently across all network devices. For example, multiple changes can be combined into a single atomic transaction during which either all of them take effect or none do. Simplifying the process in this way significantly reduces the risk and cost of a system failure occurring during a network configuration change. NETCONF also allows for rollbacks whereby configurations can be restored to prior versions known to be error-free. Pre-provisioning, backlogging, and replay are other functions NETCONF enables to help ensure smooth provisioning of networks.
The proliferation of management interfaces presents a significant challenge for networking equipment providers who are trying to reduce time-to-market. Carrier-grade networking products are currently expected to support a command line interface (CLI), SNMP, a Web interface, and increasingly a NETCONF interface. Supporting multiple interfaces with separate software adapter layers for each managed object creates unnecessary development and maintenance overhead. The alternative is to configure applications to a common data model and auto-render the on-device management interfaces from it. Besides reducing development time, this approach future-proofs the system. When a new upper-level management interface is needed, developers can leverage the existing modeling and instrumentation.
Configuration management software must also handle more network performance and reliability demands. Today’s carrier-grade networks require transaction engines that can scale to tens of thousands of operations per minute and a database tuned for configuration management. Management systems must be able to support a range of networking hardware including AdvancedTCA, blade servers, and appliances, together with their applicable high-availability configurations. Additionally, modern management systems require role based access control, advanced authentication, fine grained authorization, audit trails, and support for viewing and managing a cluster of network elements from a single console.
The increasing complexity of networks and the demand for new services require improved configuration management systems. Operators can no longer afford to provision networks manually. Automated configuration management is essential to reduce costs, increase reliability, and respond to customer needs.
Tomas Mellgren is Product Manager for ConfD at Tail-f Systems. You can reach him at tomas@tail-f.com.