In a typical DNS deployment, a DNS server hosts and serves data for the domain(s); when an incoming DNS query for, e.g. web server appears, DNS server then replies it with IP resolved for the web server. This mechanism is designed for translating domain name into IP address, while it does not check if there are any network outages or congestion when replying. In case a link failure occurs, DNS server might resolve the web server to the IP addresses that are associated with the failed link. Thus, the incoming request would not be able to access the web server in this case.
Incoming requests to corporate hosted services
Problems to be Solved:
> Hosted service disruption during planned network downtime.
> Hosted services unavailable to incoming requests due to either WAN outages or congestion.
> Changing network status and conditions
> Bandwidth efficiency for uplinks
> Bandwidth scalability
Solution: Network Failover for Incoming requests
> Add redundant WAN links.
> Direct incoming requests to the remaining active path in case links network outages occur.
Inbound Failover
Solution: Inbound Load Balancing
> Direct incoming requests to the active or least-loaded or best-performing paths.
> Effectively distribute incoming requests to all active paths.
> Add WAN links for more uplink bandwidth necessary.
Inbound Load Balancing