Before you will start to install patch you need:
Please confirm you are running version 8.0.0.807, 8.0.0.817, 8.0.0.831, 8.0.0.917 or 8.0.0.2018 prior to installing this update. You can check this under Help | About in Veeam Backup & Replication console. After upgrading, your build will be version 8.0.0.2021
Prior to installing this update please reboot the Veeam server to clear any locks on the Veeam services and when the reboot is done, please stop all the Veeam services and apply the update.
After installing the update, please start the Veeam services, open the console and allow Veeam B&R to update its components.
After upgrading to vCenter Server 6.0, due to vSphere 6 using new unique tag IDs, you must edit all existing jobs that leverage vSphere tags and re-add all required tags.
To obtain this update, please click here (you need to be logged in to download the update).
To obtain Veeam ONE v8 Update 2, please follow this link
here is release notes link:
http://www.veeam.com/kb2024