This article raises some fair points, but it comes off as a bit biased and compares extremes a few times.
"Geographic Redundancy and Diversity
The Cloud Way: The cloud out of the box gives you the power to instantiate your services in geographically diverse regions.
The Traditional Data Center: To do the same with your own data centers is very costly / time consuming / resource intensive. "
There are many ISP's that allow you to rent multiple servers spread across multiple datacenters. As a matter of fact, we are with an ISP that has 5 geographically separated datacenters and renting dedicated servers there. It's not that different from setting it up in the cloud, you run into the same hard problems: replication, master/slave, latency, split brain problems, etc.
"Load Balancing & Basic Monitoring
The Cloud Way: The cloud provides this at a basic level and gets you off the ground quickly.
The Traditional Data Center: You don’t need to implement your own solution unless you really need to do some advanced loadbalancing for example."
This is another thing that many regular hosting providers offer. Monitoring and load balancing is not something that's unique to clouds.
All in all, while I agree that in some situations, a cloud offers you more possibilities to easily achieve high availability, some of the hardest problems remain unsolved. When you actually want very high availability and consistency across multiple geographically separated locations, cloud or no cloud, it's still going to be incredibly hard to solve.
> When you actually want very high availability and consistency across multiple geographically separated locations, cloud or no cloud, it's still going to be incredibly hard to solve.
But then... you're talking about a niche. Granted, no consolation if you are in it, but most people are not.
This is a pretty rosy view considering that AFAIK basic HA tasks like taking over an IP address from a failed machine is much slower in the cloud. And let's hope your HA software doesn't want to use multicast...
The need for HA software to remap ip's should not be there if the service has been designed in a stateless manner. As soon as a service goes down the balancer should send the next request to the next node.
In addition - At the entrance of the cloud(external ip's of the balancer) - I would suggest dnsmadeasy that can do round robin dns along with dns monitoring with a low ttl of 5 minutes that in case of failure can change your A records.
So the service should be designed with not having to rely on ip re-assignments.
"Geographic Redundancy and Diversity
The Cloud Way: The cloud out of the box gives you the power to instantiate your services in geographically diverse regions.
The Traditional Data Center: To do the same with your own data centers is very costly / time consuming / resource intensive. "
There are many ISP's that allow you to rent multiple servers spread across multiple datacenters. As a matter of fact, we are with an ISP that has 5 geographically separated datacenters and renting dedicated servers there. It's not that different from setting it up in the cloud, you run into the same hard problems: replication, master/slave, latency, split brain problems, etc.
"Load Balancing & Basic Monitoring
The Cloud Way: The cloud provides this at a basic level and gets you off the ground quickly.
The Traditional Data Center: You don’t need to implement your own solution unless you really need to do some advanced loadbalancing for example."
This is another thing that many regular hosting providers offer. Monitoring and load balancing is not something that's unique to clouds.
All in all, while I agree that in some situations, a cloud offers you more possibilities to easily achieve high availability, some of the hardest problems remain unsolved. When you actually want very high availability and consistency across multiple geographically separated locations, cloud or no cloud, it's still going to be incredibly hard to solve.