Chapter 16. Configuring additional devices in an IBM Z or IBM LinuxONE environment
After installing OpenShift Container Platform, you can configure additional devices for your cluster in an IBM Z® or IBM® LinuxONE environment, which is installed with z/VM. The following devices can be configured:
- Fibre Channel Protocol (FCP) host
- FCP LUN
- DASD
- qeth
You can configure devices by adding udev rules using the Machine Config Operator (MCO) or you can configure devices manually.
The procedures described here apply only to z/VM installations. If you have installed your cluster with RHEL KVM on IBM Z® or IBM® LinuxONE infrastructure, no additional configuration is needed inside the KVM guest after the devices were added to the KVM guests. However, both in z/VM and RHEL KVM environments the next steps to configure the Local Storage Operator and Kubernetes NMState Operator need to be applied.
Additional resources
16.1. Configuring additional devices using the Machine Config Operator (MCO)
Tasks in this section describe how to use features of the Machine Config Operator (MCO) to configure additional devices in an IBM Z® or IBM® LinuxONE environment. Configuring devices with the MCO is persistent but only allows specific configurations for compute nodes. MCO does not allow control plane nodes to have different configurations.
Prerequisites
- You are logged in to the cluster as a user with administrative privileges.
- The device must be available to the z/VM guest.
- The device is already attached.
-
The device is not included in the
cio_ignore
list, which can be set in the kernel parameters. You have created a
MachineConfig
object file with the following YAML:apiVersion: machineconfiguration.openshift.io/v1 kind: MachineConfigPool metadata: name: worker0 spec: machineConfigSelector: matchExpressions: - {key: machineconfiguration.openshift.io/role, operator: In, values: [worker,worker0]} nodeSelector: matchLabels: node-role.kubernetes.io/worker0: ""
16.1.1. Configuring a Fibre Channel Protocol (FCP) host
The following is an example of how to configure an FCP host adapter with N_Port Identifier Virtualization (NPIV) by adding a udev rule.
Procedure
Take the following sample udev rule
441-zfcp-host-0.0.8000.rules
:ACTION=="add", SUBSYSTEM=="ccw", KERNEL=="0.0.8000", DRIVER=="zfcp", GOTO="cfg_zfcp_host_0.0.8000" ACTION=="add", SUBSYSTEM=="drivers", KERNEL=="zfcp", TEST=="[ccw/0.0.8000]", GOTO="cfg_zfcp_host_0.0.8000" GOTO="end_zfcp_host_0.0.8000" LABEL="cfg_zfcp_host_0.0.8000" ATTR{[ccw/0.0.8000]online}="1" LABEL="end_zfcp_host_0.0.8000"
Convert the rule to Base64 encoded by running the following command:
$ base64 /path/to/file/
Copy the following MCO sample profile into a YAML file:
apiVersion: machineconfiguration.openshift.io/v1 kind: MachineConfig metadata: labels: machineconfiguration.openshift.io/role: worker0 1 name: 99-worker0-devices spec: config: ignition: version: 3.2.0 storage: files: - contents: source: data:text/plain;base64,<encoded_base64_string> 2 filesystem: root mode: 420 path: /etc/udev/rules.d/41-zfcp-host-0.0.8000.rules 3
16.1.2. Configuring an FCP LUN
The following is an example of how to configure an FCP LUN by adding a udev rule. You can add new FCP LUNs or add additional paths to LUNs that are already configured with multipathing.
Procedure
Take the following sample udev rule
41-zfcp-lun-0.0.8000:0x500507680d760026:0x00bc000000000000.rules
:ACTION=="add", SUBSYSTEMS=="ccw", KERNELS=="0.0.8000", GOTO="start_zfcp_lun_0.0.8207" GOTO="end_zfcp_lun_0.0.8000" LABEL="start_zfcp_lun_0.0.8000" SUBSYSTEM=="fc_remote_ports", ATTR{port_name}=="0x500507680d760026", GOTO="cfg_fc_0.0.8000_0x500507680d760026" GOTO="end_zfcp_lun_0.0.8000" LABEL="cfg_fc_0.0.8000_0x500507680d760026" ATTR{[ccw/0.0.8000]0x500507680d760026/unit_add}="0x00bc000000000000" GOTO="end_zfcp_lun_0.0.8000" LABEL="end_zfcp_lun_0.0.8000"
Convert the rule to Base64 encoded by running the following command:
$ base64 /path/to/file/
Copy the following MCO sample profile into a YAML file:
apiVersion: machineconfiguration.openshift.io/v1 kind: MachineConfig metadata: labels: machineconfiguration.openshift.io/role: worker0 1 name: 99-worker0-devices spec: config: ignition: version: 3.2.0 storage: files: - contents: source: data:text/plain;base64,<encoded_base64_string> 2 filesystem: root mode: 420 path: /etc/udev/rules.d/41-zfcp-lun-0.0.8000:0x500507680d760026:0x00bc000000000000.rules 3
16.1.3. Configuring DASD
The following is an example of how to configure a DASD device by adding a udev rule.
Procedure
Take the following sample udev rule
41-dasd-eckd-0.0.4444.rules
:ACTION=="add", SUBSYSTEM=="ccw", KERNEL=="0.0.4444", DRIVER=="dasd-eckd", GOTO="cfg_dasd_eckd_0.0.4444" ACTION=="add", SUBSYSTEM=="drivers", KERNEL=="dasd-eckd", TEST=="[ccw/0.0.4444]", GOTO="cfg_dasd_eckd_0.0.4444" GOTO="end_dasd_eckd_0.0.4444" LABEL="cfg_dasd_eckd_0.0.4444" ATTR{[ccw/0.0.4444]online}="1" LABEL="end_dasd_eckd_0.0.4444"
Convert the rule to Base64 encoded by running the following command:
$ base64 /path/to/file/
Copy the following MCO sample profile into a YAML file:
apiVersion: machineconfiguration.openshift.io/v1 kind: MachineConfig metadata: labels: machineconfiguration.openshift.io/role: worker0 1 name: 99-worker0-devices spec: config: ignition: version: 3.2.0 storage: files: - contents: source: data:text/plain;base64,<encoded_base64_string> 2 filesystem: root mode: 420 path: /etc/udev/rules.d/41-dasd-eckd-0.0.4444.rules 3
16.1.4. Configuring qeth
The following is an example of how to configure a qeth device by adding a udev rule.
Procedure
Take the following sample udev rule
41-qeth-0.0.1000.rules
:ACTION=="add", SUBSYSTEM=="drivers", KERNEL=="qeth", GOTO="group_qeth_0.0.1000" ACTION=="add", SUBSYSTEM=="ccw", KERNEL=="0.0.1000", DRIVER=="qeth", GOTO="group_qeth_0.0.1000" ACTION=="add", SUBSYSTEM=="ccw", KERNEL=="0.0.1001", DRIVER=="qeth", GOTO="group_qeth_0.0.1000" ACTION=="add", SUBSYSTEM=="ccw", KERNEL=="0.0.1002", DRIVER=="qeth", GOTO="group_qeth_0.0.1000" ACTION=="add", SUBSYSTEM=="ccwgroup", KERNEL=="0.0.1000", DRIVER=="qeth", GOTO="cfg_qeth_0.0.1000" GOTO="end_qeth_0.0.1000" LABEL="group_qeth_0.0.1000" TEST=="[ccwgroup/0.0.1000]", GOTO="end_qeth_0.0.1000" TEST!="[ccw/0.0.1000]", GOTO="end_qeth_0.0.1000" TEST!="[ccw/0.0.1001]", GOTO="end_qeth_0.0.1000" TEST!="[ccw/0.0.1002]", GOTO="end_qeth_0.0.1000" ATTR{[drivers/ccwgroup:qeth]group}="0.0.1000,0.0.1001,0.0.1002" GOTO="end_qeth_0.0.1000" LABEL="cfg_qeth_0.0.1000" ATTR{[ccwgroup/0.0.1000]online}="1" LABEL="end_qeth_0.0.1000"
Convert the rule to Base64 encoded by running the following command:
$ base64 /path/to/file/
Copy the following MCO sample profile into a YAML file:
apiVersion: machineconfiguration.openshift.io/v1 kind: MachineConfig metadata: labels: machineconfiguration.openshift.io/role: worker0 1 name: 99-worker0-devices spec: config: ignition: version: 3.2.0 storage: files: - contents: source: data:text/plain;base64,<encoded_base64_string> 2 filesystem: root mode: 420 path: /etc/udev/rules.d/41-dasd-eckd-0.0.4444.rules 3
16.2. Configuring additional devices manually
Tasks in this section describe how to manually configure additional devices in an IBM Z® or IBM® LinuxONE environment. This configuration method is persistent over node restarts but not OpenShift Container Platform native and you need to redo the steps if you replace the node.
Prerequisites
- You are logged in to the cluster as a user with administrative privileges.
- The device must be available to the node.
- In a z/VM environment, the device must be attached to the z/VM guest.
Procedure
Connect to the node via SSH by running the following command:
$ ssh <user>@<node_ip_address>
You can also start a debug session to the node by running the following command:
$ oc debug node/<node_name>
To enable the devices with the
chzdev
command, enter the following command:$ sudo chzdev -e <device>
Additional resources
- chzdev - Configure IBM Z® devices (IBM® Documentation)
- Persistent device configuration (IBM® Documentation)
16.3. RoCE network Cards
RoCE (RDMA over Converged Ethernet) network cards do not need to be enabled and their interfaces can be configured with the Kubernetes NMState Operator whenever they are available in the node. For example, RoCE network cards are available if they are attached in a z/VM environment or passed through in a RHEL KVM environment.
16.4. Enabling multipathing for FCP LUNs
Tasks in this section describe how to manually configure additional devices in an IBM Z® or IBM® LinuxONE environment. This configuration method is persistent over node restarts but not OpenShift Container Platform native and you need to redo the steps if you replace the node.
On IBM Z® and IBM® LinuxONE, you can enable multipathing only if you configured your cluster for it during installation. For more information, see "Installing RHCOS and starting the OpenShift Container Platform bootstrap process" in Installing a cluster with z/VM on IBM Z® and IBM® LinuxONE.
Prerequisites
- You are logged in to the cluster as a user with administrative privileges.
- You have configured multiple paths to a LUN with either method explained above.
Procedure
Connect to the node via SSH by running the following command:
$ ssh <user>@<node_ip_address>
You can also start a debug session to the node by running the following command:
$ oc debug node/<node_name>
To enable multipathing, run the following command:
$ sudo /sbin/mpathconf --enable
To start the
multipathd
daemon, run the following command:$ sudo multipath
Optional: To format your multipath device with fdisk, run the following command:
$ sudo fdisk /dev/mapper/mpatha
Verification
To verify that the devices have been grouped, run the following command:
$ sudo multipath -II
Example output
mpatha (20017380030290197) dm-1 IBM,2810XIV size=512G features='1 queue_if_no_path' hwhandler='1 alua' wp=rw -+- policy='service-time 0' prio=50 status=enabled |- 1:0:0:6 sde 68:16 active ready running |- 1:0:1:6 sdf 69:24 active ready running |- 0:0:0:6 sdg 8:80 active ready running `- 0:0:1:6 sdh 66:48 active ready running