Hey Alex,

• For question 1
  
  
• your understanding of the “host-update” use case is correct
  i.e.
• power on host which dhcp’s on mgmt. network
• host gets auto discovered by controller-0 and auto-provisioned without personality
• user uses host-update to set personality
• controller-0 installs software for that personality
  
  
• “host-add” use case is sort of the opposite … configure host first, then power it on
  i.e.
• user uses “host-add” command and configures host in system’s inventory with
  identifying information such as BMC IP Address, mgmt. network MAC, etc.,
  and the host’s personality
• user uses “host-power-on” command to power on the host via the BMC
• host powers on, dhcp’s on mgmt. network
• gets recognized by controller-0 from previously configured host info (e.g. mgmt. MAC, …)
• controller-0 installs software for the previously configured personality of this host.
  
  
• For question 2
• pretty sure answer is no
• I believe starlingx sysinv/mtce/swmgmt software will always want to install software on a new host
• … although, thinking of question 1,
  you could try doing a host-add with the identifying information of controller-1, and power on controller-1 and
  see if controller-0 will try to re-install or not
• no matter what there will be software versioning checks that happen at boot time to ensure controller-1 is
  running the same software as controller-0 and is patch current based on controller-0’s applied patches
• … however, why do  you want to do this ?
• like is this a real use case ?

Greg.

From: Williams, Alexander <Alexander.Williams@commscope.com>
Sent: Monday, June 7, 2021 12:23 PM
To: starlingx-discuss@lists.starlingx.io
Subject: [Starlingx-discuss] Adding hosts (Bare Metal AIO Duplex)

[Please note: This e-mail is from an EXTERNAL e-mail address]

Hi all,

My current understanding is that whenever adding a host (esp. controller-1) using the system host-update command after a PXE boot, StarlingX will install the base image and then perform the configuration steps to make it a controller, worker, etc., overwriting anything that was previously installed on the machine.

1. Is my understanding of host-update correct, or am I missing something important here? Does host-add do the same thing, but gets run on controller-0 before booting and not after?
2. If I install the StarlingX image on a server that will become controller-1, is there any way to add it to the host list of controller-0 and configure its personality without the server reinstalling StarlingX?

Best,

Alex