As the Joomla Forum grows and demands on hardware increase, some of the community members that frequent the popular message board have noticed some performance issues, and have even experienced site errors due to the increase in traffic. As more and more users took advantage of the Advanced Search feature, the site began to display the message: "Sorry but the board is temporarily unavailable, please try again in a few minutes." This began to occur with some regularity.
"To solve that problem, our sponsor of Joomla's infrastructure Rochen increased the performance of Joomla Forum by adding a second frontend webserver combined with a load balancer," states Peter Martin in a Joomla! Community Portal blog post.
While the solution did provide some much needed relief and help to increase speed and performance of the forum, administrators did experience some "teething problems" as Martin calls them. Some users were automatically put on the ban list, and some phpBB3 pages were resulting in MySQL errors; however, the problems have been addressed, and the system is reported to be running smoothly.
For more detailed information on the upgrade, see the post in the Community Portal.