Important Update - On Mar 20 2018, VMware VMSA-2018-0004.3 announced that CVE-2017-5715 (Spectre-2) mitigation is now included in the latest patch that you should be using instead of the older patch featured in the original article below . You'll find the newer article here:

Article below as it originally appeared.

VMware vCenter Server 6.5.0b Release Notes | 14 MARCH 2017 | ISO Build 5178943

Warning:

vCenter/VCSA 6.5 should be upgraded to 6.5.0b (aka 6.5 b) before upgrading your host(s) to ESXi 6.5.0a, which is still the latest ESXi version by the way.

There's a nice benefit to 6.5.0b, see also the closely related article:

Once in a while, things are easy. One of the selling points of making the big move from vCenter+Windows to VCSA has been the ease of VCSA upgrades through the handy VAMI web UI. Yep, works as advertised, just like it did when going from 6.5 to 6.5.0.a back in February. This is a very easy upgrade, as shown screen-by-screen walk through below, and in the video below.

VCSA 6.5.x with internet access

If your VCSA has no internet access, follow the offline install procedure at:

Warning:

Do this VCSA 6.5.0b upgrade in a test environment first! Before attempting, you should be sure to have a full backup, such as the simple native VCSA backup button seen at top-right. You can also use a 3rd party backup solution. At a minimum, you can do a snapshot of this VCSA VM before upgrading, make sure everything works alright, then remove the snapshot, ideally within a day or so, to avoid performance degradation

If you're looking for how you get from 6.0.x to 6.5, that's more of a migration, and the right article for you is over here:

How to easily update your VMware vCenter Server Appliance to VCSA 6.5

Nov 20 2016

If you're looking for how you get from ESXi 6.5.x to 6.5.0a, that article is over here:

How to easily update your VMware Hypervisor to ESXi 6.5.0a

Feb 07 2017

It looks like you have JavaScript disabled. Click here to view the video above. VCSA upgrade to 6.5.0b using VAMI.

Takes about 2 to 3 minutes to upgrade, if your VCSA VM is located on an SSD based datastore, such as the Samsung 960 EVO 1TB M.2 NVMe SSD I used for my home datacenter, featured in this video.

in your browser, go to your VCSA IP or Name:5480

login with root and your password

along the left edge of DCUI, click 'Update', then click on 'Check Updates'

click 'Check Repository'

click on 'I accept' checkbox, then click on 'Install'

wait for a bit, on SSDs, a bit is less than 2 minutes

wow, you're done already

at left, click on 'Summary', then at right, click on 'Reboot'

login with root and your password