Edit the iPXE Embedded Boot Script

Manually adjust the iPXE embedded boot script to change the order of network interfaces for DHCP request. Changing the order of network interfaces for DHCP requests helps improve boot time performance.

Prerequisites

This procedure requires administrative privileges.

Procedure

  1. (ncn-mw#) Edit the ConfigMap using one of the following options.

    NOTE Save a backup of the ConfigMap before making any changes.

    The following is an example of creating a backup:

    kubectl get configmap -n services cray-ipxe-bss-ipxe \
        -o yaml > /root/cray-ipxe-bss-ipxe-backup.yaml

    Administrators can add, remove, or reorder sections in the ConfigMap related to the interface being used.

    In the following example, the net2 section is located before the net0 section. If an administrator wants net0 to be run first, they could move the net0 section to be located before the net2 section.

    :net2
dhcp net2 || goto net2_stop
echo net2 IPv4 lease: ${ip} mac: ${net2/mac}
chain --timeout 10000 https://api-gw-service-nmn.local/apis/bss/boot/v1/bootscript?mac=${net2/mac} || echo Failed to retrieve next chain from Boot Script Service over net2 (https://api-gw-service-nmn.local/apis/bss/boot/v1/bootscript?mac=${net2/mac} && goto net2_stop
:net2_stop
ifclose net2 || echo No routes to drop.

:net0
dhcp net0 || goto net0_stop
echo net0 IPv4 lease: ${ip} mac: ${net0/mac}
chain --timeout 10000 https://api-gw-service-nmn.local/apis/bss/boot/v1/bootscript?mac=${net0/mac} || echo Failed to retrieve next chain from Boot Script Service over net0 (https://api-gw-service-nmn.local/apis/bss/boot/v1/bootscript?mac=${net0/mac} && goto net0_stop
:net0_stop
ifclose net0 || echo No routes to drop.

    • Option 1: Edit the cray-ipxe-bss-ipxe ConfigMap directly.

      kubectl edit configmap -n services cray-ipxe-bss-ipxe

    • Option 2: Edit the ConfigMap by saving the file, editing it, and reloading the ConfigMap.

      1. Save the file.

        kubectl get configmap -n services cray-ipxe-bss-ipxe -o yaml > /root/cray-ipxe-bss-ipxe.yaml

      2. Edit the cray-ipxe-bss-ipxe.yaml file.

      3. Reload the ConfigMap.

        Deleting and recreating the ConfigMap will reload it.

        kubectl delete configmap -n services cray-ipxe-bss-ipxe
kubectl create -f /root/cray-ipxe-bss-ipxe.yaml

  2. (ncn-mw#) Delete the iPXE pods to ensure the updated ConfigMap will be used.

    1. Find the pod ID.

      kubectl -n services get pods|grep cray-ipxe

      Example output:

      cray-ipxe-aarch64-5cdd74f889-wrkj7  2/2     Running        0       10d
cray-ipxe-x86-64-5b88cb79c-wb22l    2/2     Running        0       10d

    2. Delete the pod.

      Replace CRAY-IPXE_POD_ID with the value returned in the previous step. In this example, the pod IDs are cray-ipxe-aarch64-5cdd74f889-wrkj7' and 'cray-ipxe-x86-64-5b88cb79c-wb22l.

      kubectl -n services delete pod CRAY-IPXE_POD_ID

Wait about 30 seconds for the iPXE binary to be regenerated, and then the nodes will pick up the new ipxe.efi binary.