Hello everyone,
I'm reviewing Drupal after last looking at it two years ago.
I'm impressed with how far Drupal has come since then!
However, I'm disappointed in trying to figure out how well it scales in a n-tier architecture and how it might support a development > staging > production methodology as separate instances for updates as well as publishing. Let me elaborate:
First, after reviewing the FAQ, I see that http://drupal.org/node/202799#serverhw points to a non-existent page that might give me some insight into how drupal.org infrastructure is set up as well as what kind of demand/traffic it supports.
What I'd like to see is that you've got a classic three tier architecture which allows scalability/failover on all tiers, e.g.:
[Internet] -> [Firewall] -> [Caching proxy or web server 1..n] -> [Firewall for DMZ] -> [Drupal App Server 1..n] -> [Firewall] -> [MySQL Database cluster, node 1..n]
where 1..n represents 1+ servers, up to a count of n. Such as: server 1, server 2, server 3, ... up to server #n.
Can Drupal support that? Is there any evidence or technical case studies that illustrate?
Second, the development to staging to production methodology question.