Your server must meet the following requirements before vBulletin can be installed on the machine. Most shared-environment hosting providers meet these qualifications already. If you're unsure, you can always use vBulletin Cloud to host your vBulletin website.
Minimum Requirements
vBulletin is a web-based application and as such has a few minimum requirements. To run vBulletin, you need a web hosting provider that includes the following on their systems:
PHP version: 7.1.0
MySQL version: 5.6.10 (see note below)
As an alternative to MySQL, you can use MariaDB version: 10+
A pre-registered domain name
200 Megabytes of hard drive space
128 MB per PHP Script.
Rewrite Engine - A rewrite engine is needed for vBulletin's Friendly URL...