(also DNS backup, DNS fallback, DNS failsafe)
DNS failover definition
DNS failover is a technique used to ensure the high availability and reliability of a website or web service by automatically redirecting traffic to a backup or secondary IP address or server if the primary server fails or becomes unreachable. This technique is part of a broader set of failover methods, which are crucial for maintaining the uptime of critical online services.
See also: DNS server
DNS failover examples
- Website hosting: If a website’s primary server goes down, DNS failover can redirect traffic to a backup server, preventing the website from going offline.
- Cloud services: In a cloud-based application, DNS failover can be used to switch traffic between different cloud instances in case of a failure.
Preventing DNS failover issues
- Ensure that your secondary server or IP address is always ready to take over the traffic in case of a primary server failure.
- Keep your DNS records updated to ensure that the failover process happens smoothly.
- Use a VPN to prevent DNS leaks that could expose your real IP address during a failover situation.
DNS failover benefits
DNS failover offers numerous advantages for organizations and individuals relying on the internet for critical services. Some of these benefits include:
- Improved reliability: By automatically redirecting traffic to a backup server or IP address in case of primary server failure, DNS failover ensures that your website or online service remains accessible to users.
- High availability: DNS failover helps maintain high uptime for critical online services by quickly switching traffic to a secondary server or IP address when necessary, minimizing downtime and disruption for users.
- Better user experience: With DNS failover in place, users experience minimal interruptions to their access to your online services, contributing to better overall user satisfaction and a positive brand reputation.
- Enhanced disaster recovery: In the case of natural disasters or other unforeseen events that could affect the primary server’s availability, DNS failover provides a safeguard by allowing a seamless transition to a secondary server or IP address, ensuring continuity of service.
- Load balancing: DNS failover can also be used in combination with load balancing to distribute traffic evenly across multiple servers, improving performance and reducing the risk of server overloads.
- Easy scalability: As your online services grow and demand increases, DNS failover allows you to easily add more servers or IP addresses to handle the additional traffic, ensuring smooth scalability.