To begin the cluster Installation, create a bootstrap node. The bootstrap node is necessary to create the persistent control plane that the master nodes manage. After the initial minimum cluster with at least three master and two worker nodes is operational, remove the bootstrap node and convert it to a worker node, if required.
To create a bootstrap node:
- Connect to the iDRAC of the bootstrap node and open the virtual console.
- In the iDRAC GUI, click Configuration and select BIOS Settings.
- Expand Network Settings.
- Set PXE Device1 to Enabled.
- Expand PXE Device1 Settings.
- Select NIC in Slot 2 Port 1 Partition 1 as the interface.
- Scroll to the bottom of the Network Settings section and click Apply.
The system boots automatically into the PXE network and displays the PXE menu, as shown in the following figure:

Figure 3. iDRAC console PXE menu
- Select bootstrap, and then perform the following steps after node installation is complete but before the node automatically reboots into the PXE:
- Press F2 to enter System Setup.
- Select System BIOS > Boot Settings > UEFI Boot Settings > UEFI Boot Sequence.
- Select PXE Device 1 and click -.
- Repeat the preceding step until PXE Device 1 is at the bottom of the boot menu.
- Click OK and then click Back.
- Click Finish and save the changes.
- Let the node boot into the hard drive where the operating system is installed.
- After the node comes up, check that the hostname in the iDRAC console is displayed as bootstrap.

Figure 4. iDRAC console bootstrap node
- As user core in CSAH, run ssh bootstrap to ensure that the proper IP address is assigned to bond0.
- From the CSAH node, as user core, ssh to the bootstrap node and verify that ports 6443 and 22623 are listening.
Allow approximately 30 minutes for the ports to show up as listening. If the ports are listening after that time, reinstall the bootstrap by repeating the preceding steps.
[core@csah ~]$ ssh bootstrap sudo ss -tulpn | grep -E '6443|22623'
tcp LISTEN 0 128 *:6443 *:* users:(("kube-etcd-signe",pid=9150,fd=3))
tcp LISTEN 0 128 *:22623 *:* users:(("machine-config-",pid=8924,fd=5))