ESXi Updates without Maintenance Mode

[Hans Meiser]

VCenter 7.0.3 Build 24322018

Hello,

we are in the situation that our ESXi Hosts are up-to-date, all Updates are installed. Now one new update appeared. This is just a new VMTools package which ESXi wants to install. This update seems to have no impact. In VCenter overview there is neither a hint to switch to maintenance mode nor the need of a reboot.
So my question is: is it really safe to install this update on a DRS-full auto cluster with multiple hosts and multiple VMs without maintenance, just with running VMs? Or should i do i precautionally the classic way(empty ESXi Host+maintenance mode)? 

Thanks you,
Hans

[Andrea Consalvi]

Hi Hans,

If the update is strictly limited to the VMware Tools package, then yes it's safe to install it without putting the host into maintenance mode and without powering off or migrating VMs.

VMware Tools updates are not tied to the ESXi hypervisor core, so they don't require host reboot or impact running workloads. Once the package is available on the host, you can later apply the updated Tools per-VM as needed (or even automate it with VM policies).

Unless the update includes any VIBs that modify system-level components  which would usually be clearly indicated in vCenter you don't need to enter maintenance mode. Still, if you want to be cautious, you could apply it first on a non-critical host.

[PaulB2]

I did some of these last week, first on test and then on prod. No reboots, no issues.

------------------------------
-pb
------------------------------

[Hans Meiser]

Hello,

yes it seems to works like promised. One really easy update this time.

Thanks,
Hans