Errno 28 When Trying to Update VMware ESXi

When trying to update/upgrade ESXi 6.7 (via software profile update command) you may run into the following error message:

[OSError]
[Errno 28] No space left on device
Please refer to the log file for more details.

The solution is to set the host swap to use a datastore. In vSphere Web Access:

1. Navigate to Host->Manage->System->Swap. On a fresh install, the Datastore setting  is usually set to No.
2. Choose Edit Settings, select a valid Datastore in the drop down menu, then Save.
3. Now you are ready to issue the profile update command again to patch ESXi