If you check the discussion forums of forum software such as vBulletin, Xenforo, and PHPBB, you will see a lot of discussions about hosting.
Online communities can take a lot of resources to manage due to the large number of users that are browsing a website at the same time. Every time a page is loaded, many different files and database tables need to be accessed and updated.
This is why forum owners outgrow their shared hosting and VPS hosting plans once their forum becomes popular.
Hosting companies that focus solely on hosting discussion forums have a wealth of experience in this area. They know how to configure servers correctly for hosting online communities and are familiar with common hosting problems that arise with forums.
Nexcess are a USA based website hosting company that have hosting options available in the USA, UK, and Australia. Their company focuses on offering hosting for four website platforms: WordPress, Magento, ExpressionEngine, and vBulletin
Their shared hosting plans for vBulletin start from $11.95 per month. This will get you 10GB of storage, 150GB of bandwidth, and access to 16GB of RAM.
Dedicated hosting plans for WordPress users start from $449.45.
For 13 years I hosted the majority of my websites on one hosting plan. After experiencing downtime during the first half of 2013, I decided to move my forums to a separate host. That meant that if my WordPress websites go down, my forums are not affected, and vice versa.
Nimbus are a UK hosting company who focus on hosting discussion forums. I would have saved money by hosting my forums elsewhere, however the premium was worth it as they know how to optimise servers for forums. Their support was great from the start too, so I have no problem recommending them to anyone who is looking for a forum hosting company.
I migrated my websites away from NimbusHosting when I upgraded to a dedicated server.