Hi, You can use it to update without doing a new install. kb.vmware.com/.../search.do;cmd=displayKC&externalId=2109711#Inter 
Hello I am currently running my PowerEdge T110 II with VMware ESXi 6.0 - Dell Customized image. I see as of April 15 2016 Dell has released VMware ESXi 6.0 Update 2 and I would like to update my system. On the download page I see there is an option to download and ISO file. I am wondering if this install will completely wipeout my existing VMware ESXi 6.0 - Dell Customized and all settings and I have to start all over or will the Update 2 ISO just "upgrade" my existing system?
Upgrade to VMware ESXi 6.0 Update 2 from VMware ESXi 6.0