vSphere Installation Guide for Unsupported Hardware

1.1 Hardware Requirements (Minimum for Workaround)

• CPU: Intel Xeon E5-2600 series (Sandy Bridge-EP) or equivalent that supports the XSAVE instruction
• RAM: Minimum 8 GB (strongly recommended ≥ 16–32 GB)
• Boot device: ≥ 32 GB persistent storage (local SSD/HDD preferred; avoid SD/USB as primary boot device)
• Network: At least one Gigabit Ethernet adapter
• BIOS: Latest available for the platform, UEFI mode preferred

1.2 Firmware & BIOS Preparation

1. Update the following components to the latest available versions for R720 via Dell Support / Dell Repository Manager:
   • System BIOS, iDRAC, PERC controller (H710 / H710P / etc.), Network adapters, Lifecycle Controller
2. BIOS Settings (recommended):
   • Boot Mode: UEFI
   • Virtualization Technology (VT-x): Enabled
   • VT-d: Enabled
   • Execute Disable Bit (NX/XD): Enabled
   • Secure Boot: Can be disabled temporarily if signature issues occur
   • Integrated RAID Controller: Enabled
   • Firmware Device Order (FDO) on PERC: Disabled (not supported by ESXi)

1.3 Backup Requirements

• Full backup of all virtual machines (Veeam, OVF export, or equivalent)
• Export host configuration / Host Profile
• Document: management IP, DNS, NTP, vSwitch/DVS settings, datastore names, license keys, storage configuration

1.4 Software Download

1. Log in to the Broadcom Support Portal.
2. Navigate to VMware vSphere → 8.0 → Custom ISO.
3. Search for Dell and download the latest Dell Customized ESXi 8.0 U3 image if available.
4. If no suitable Dell Custom image exists for older platforms (common for R720), download the standard VMware ESXi 8.0 U3 ISO.
5. Prepare bootable media: USB (use Rufus in DD mode) or iDRAC Virtual Media

1.5 vCenter Consideration

If the host is managed by vCenter, upgrade vCenter Server to version 8.x before upgrading the ESXi hosts (official VMware sequence).

Example full line:

runweasel cdromBoot allowLegacyCPU=true

3.1 Interactive Upgrade (ISO Method)

1. Place the host in Maintenance Mode and evacuate or shut down all VMs.
2. Boot from the ESXi 8.0 ISO (Dell Custom or standard).
3. Press Shift + O and add allowLegacyCPU=true.
4. Select the Upgrade option (preserves existing VMFS datastores and most configuration).
5. Acknowledge the CPU warning and complete the upgrade.
6. Reboot the host.

3.2 CLI Upgrade Method (esxcli)

1. Place the host in Maintenance Mode.
2. Upload the offline depot ZIP (Dell Custom or standard) to a datastore.
3. Enable SSH and run:

esxcli software profile update \
  -d /vmfs/volumes/<datastore-name>/<ESXi-8.0-U3-bundle>.zip \
  -p <profile-name> \
  --no-hardware-warning

1. Reboot the host:

reboot

3.3 Kickstart / Automated Installation

Add the following options to the kickstart file:

install --firstdisk --overwritevmfs --ignoreprereqwarnings --ignoreprereqerrors --forceunsupportedinstall

Or pass allowLegacyCPU=true via the boot command line.

Save the following script as post_esxi8_unsupported_check.sh and run it after the host has booted successfully (via SSH or ESXi Shell).

#!/bin/sh
LOGFILE="/tmp/esxi8_unsupported_verify_$(date +%Y%m%d_%H%M%S).log"
exec > >(tee -a "$LOGFILE") 2>&1

echo "=== ESXi 8.0 Unsupported Hardware Post-Install Verification ==="
echo "Date: $(date)"
echo "Hostname: $(hostname)"
echo ""

echo ">>> 1. ESXi Version & Build"
vmware -v
esxcli system version get
echo ""

echo ">>> 2. CPU & Hardware Platform"
esxcli hardware cpu list | head -25
esxcli hardware platform get
echo ""

echo ">>> 3. Critical Drivers & VIBs"
echo "--- Storage Controllers (PERC / MegaRAID / Dell) ---"
esxcli software vib list | grep -iE "perc|megaraid|dell|lsi|mpt|sas"
echo ""
echo "--- Network Drivers ---"
esxcli software vib list | grep -iE "igb|ixgbe|bnx|tg3|e1000|vmxnet|nmlx|qfle|ixgbe"
echo ""
echo "--- All Dell-related VIBs ---"
esxcli software vib list | grep -i dell
echo ""

echo ">>> 4. Physical Network Adapters"
esxcli network nic list
echo ""

echo ">>> 5. Standard vSwitch Configuration"
esxcli network vswitch standard list
echo ""
esxcli network vswitch standard portgroup list
echo ""

echo ">>> 6. Storage Adapters"
esxcli storage core adapter list
echo ""
echo ">>> Storage Devices (first 20)"
esxcli storage core device list | head -40
echo ""

echo ">>> 7. Host Certificate Status"
if [ -f /etc/vmware/ssl/rui.crt ]; then
  echo "Host certificate found."
  openssl x509 -in /etc/vmware/ssl/rui.crt -noout -subject -issuer -dates 2>/dev/null || echo "Unable to parse certificate with openssl"
else
  echo "No host certificate found (standalone host or not yet joined to vCenter)"
fi
ls -la /etc/vmware/ssl/ 2>/dev/null
echo ""

echo ">>> 8. System Status"
esxcli system maintenanceMode get
esxcli system stats uptime get
esxcli network firewall get
echo ""

echo ">>> 9. Current Software Profile"
esxcli software profile get
echo ""

echo "=== Verification completed ==="
echo "Log file: $LOGFILE"
echo ""
echo "Recommended next steps:"
echo "1. Review any missing drivers (especially PERC and NIC)."
echo "2. If PERC is missing, consider copying compatible VIBs from an ESXi 7 installation."
echo "3. Join the host to vCenter and verify certificate trust."
echo "4. Monitor /var/log/vmkernel.log for the first 24-48 hours."

How to run the script:

# Enable SSH: Host Client → Manage → Services → TSM-SSH → Start
# Copy the script to the host, then:
chmod +x post_esxi8_unsupported_check.sh
sh post_esxi8_unsupported_check.sh

Additional Stabilization Tips

• After successful boot, document the exact image profile and installed VIBs.
• Monitor logs (/var/log/vmkernel.log, /var/log/vobd.log) closely for the first 48 hours.
• Avoid placing production workloads on this configuration.
• Plan migration to officially supported hardware as soon as possible.

• Dell Release Certification Matrix (RCM) and Compatibility Matrices for ESXi 8.x do not include 12th Generation PowerEdge servers (R720, etc.).
• Dell Customized Images are validated only for supported platforms listed in the official matrices.
• Using this guide places the system outside any supported RCM stack. Document the configuration as “unsupported lab environment”.

1. Keep the original ESXi 7 installation media and configuration backups.
2. If the upgrade fails critically, boot from ESXi 7 ISO and perform a fresh install or restore from backup.
3. Restore VMs from the pre-upgrade backups.

• VMware / Broadcom KB 82794 – CPU Support Deprecation and Discontinuation
• Broadcom Support Portal – VMware vSphere 8.0 Custom ISO (Dell)
• Dell Knowledge Base – How to Download and Use Dell Customized VMware ESXi Images
• VMware ESXi 8.0 Hardware Requirements documentation
• Community workarounds for allowLegacyCPU=true (William Lam, vInfrastructure Blog, etc.)