Dell PowerStore - OpenShift Machine Configuration

99-workers-multipath-conf.yaml

### Change label as appropriate

---
apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
metadata:
  name: 99-controllers-multipath-conf
  # name: 99-workers-multipath-conf
  labels:
    machineconfiguration.openshift.io/role: master
    # machineconfiguration.openshift.io/role: worker

spec:
  config:
    ignition:
      version: 3.4.0
    systemd:
      units:
      - name: "iscsid.service"
        enabled: true
      - name: multipathd.service
        enabled: true
    storage:
      files:
      - path: /etc/multipath.conf
        filesystem: root
        mode: 400
        contents:
          verification: {}
          source: data:text/plain;charset=utf-8;base64,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

patch-MachineConfiguration-avoid-rebooting-nodes.yaml

# This patch causes changes to iscsi & multipathd to apply by restarting the relevant service, instead of rebooting the node

# This only went GA for OpenShift in 4.17
# 
# https://docs.openshift.com/container-platform/4.17/machine_configuration/machine-config-node-disruption.html

---
apiVersion: operator.openshift.io/v1
kind: MachineConfiguration
metadata:
  name: cluster
  namespace: openshift-machine-config-operator
spec:
  nodeDisruptionPolicy:
    files:
    - path: /etc/multipath.conf
      actions:
      - type: Restart
        restart:
          serviceName: multipathd.service

    units:
    - name: multipathd.service
      actions:
      - type: Restart
        restart: 
          serviceName: multipathd.service
    - name: iscsid.service
      actions:
      - type: Restart
        restart: 
          serviceName: iscsid.service

Combine the multiple MachineConfig provided by Dell documentation into a single MachineConfig

https://dell.github.io/csm-docs/docs/getting-started/installation/openshift/powerstore/csmoperator/

TODODONE: Adopt Jason Kincl's method of applying changes to multipathd without rebooting the nodes

This is the /etc/multipath.conf file before base64 encoding...

defaults {
  polling_interval 5
  checker_timeout 15
  disable_changed_wwids yes
  find_multipaths no
}
devices {
  device {
    vendor                   DellEMC
    product                  PowerStore
    detect_prio              "yes"
    path_selector            "queue-length 0"
    path_grouping_policy     "group_by_prio"
    path_checker             tur
    failback                 immediate
    fast_io_fail_tmo         5
    no_path_retry            3
    rr_min_io_rq             1
    max_sectors_kb           1024
    dev_loss_tmo             10
  }
}