Comparison of Hybrid Web Cluster to a Network Attached Storage device
Network Attached Storage device
- Network Attached Storage devices, however reliable, are in themselves a single point of failure. If you unplug the NAS, none of your websites can function.
- NAS devices cannot scale. When you run out of bandwidth or disk I/O capacity on your central NAS, you have to scale vertically, which is very expensive.
Hybrid Web Cluster
- Hybrid Web Cluster has no single point of failure. The ‘redundancy invariant’ guarantees that data is sufficiently replicated at all times to cope with the failure of n nodes, and upon a failure the nodes act quickly to re-establish the redundancy. In other words, your data is always safe, and failures are dealt with quickly.
- Hybrid Web Cluster can scale linearly according to how many servers you add to the cluster. More servers = more storage capacity, and because the storage for each website is stored locally on the node which is currently live for it (and backed up to some, but not all of the other nodes) it is fast and does not suffer the performance and bandwidth-use penalties of needing to access your storage over the network.
