Proxmox VE Cluster - Chapter 007 - Hardware Prep Work on the old Harvester cluster

 Proxmox VE Cluster - Chapter 007 - Hardware Prep Work on the old Harvester cluster

A voyage of adventure, moving a diverse workload running on OpenStack, Harvester, and RKE2 K8S clusters over to a Proxmox VE cluster.

This post documents preparing the old Harvester cluster hardware for it's new Proxmox cluster use.  These microservers are three roughly decade-old Intel NUC6i3SYH devices marketed as tiny desktops.  These will be nodes proxmox11, 12, and 13, of the eventual thirteen node cluster.  These NUC microservers were the stereotypical mid-2010s homelab for VMware ESXi experimentation.  They still work great as cluster nodes for other technologies.

The specs for each microserver are quad-core i3-6100U CPU running at 2.30 GHz with upgraded 32 GB of ram and two SSD, a quarter gig SATA and a new-ish 1 TB M2/NVME SSD.  The 1 TB drive will eventually be used as part of the Ceph cluster filesystem.

Physically, these microservers are "short cubes" about the size of a CDrom and stack nicely.  They only draw a couple watts of power.  For $10 to $20 per year of electricity, a microcluster of these microservers in a home lab or experimentation lab can run somewhat less than a dozen VMs for somewhat more than a dollar per year of electricity; a price Amazon AWS simply cannot compete with.  With realistic hardware depreciation, a small VM running on this hardware costs perhaps $3 per year.

If the CMOS battery dies, it will force the NUC to only PXEboot off the LAN.  So, that's how you know if a NUC server's battery died, it no longer reboots.  If power never fails, in theory, you can disable the network boot feature so it will try to boot off the SATA SSD.  That, of course, also does not work because the BIOS defaults disable UEFI booting and Proxmox only installs (at least by default) on UEFI.  The "F10" boot menu will permit UEFI booting even if UEFI is disabled, leading to hours of confusion and delay.  In the end, replace the CMOS battery for preventative reasons, then set the BIOS to defaults, enable UEFI, and it'll probably work.

A preparation checklist:

1. Clean and wipe old servers, both installed software and physical dusting.
2. Replace the CMOS batteries which are mostly dead.  I will include a link to a Youtube video of the replacement process.
3. Relabel ethernet cables and servers.
4. Update port names in the managed Netgear ethernet switch.  VLAN config remains the same, single VLAN, untagged.
5. Remove monitoring of old server in Zabbix.
6. Verify new devices were added in Netbox.

In the next post, install Proxmox VE on the old Harvester Cluster hardware.