While network design is generally simple, there are many ways to make a mistake that will make the whole network a single point of failure. The most commonly made mistakes are as follows:
- On access and core network layers, people often use static Link Aggregation (LAG) methods instead of dynamic link control, such as Link Aggregation Control Protocol (LACP) 802.3ad. MTU values are not properly set throughout the network and CoPP filters block protocol communication between networking equipment, which causes failover not to work in case of a failure.
- When using load balancers, quite often active/passive deployments cannot failover properly from one node to the other. This is usually caused by inconsistent configuration between load balancer cluster nodes.
- Firewalls and security groups are quite often a bottleneck, and...
