In enterprise IT infrastructure, it is common to use LACP Network Bonding and VLAN Tagging.

LACP network bonding allows two or more network interfaces to be aggregated as one, thereby providing increased bandwidth and interface / cable redundancy.

VLAN Tagging allows traffics from different networks to share common physical links while being kept segregated.

To configure both in a Linux server, it is common to use nmcli . Basically, it is a two steps configuration:

Below provides an…

I have a multi-architecture Kubernetes cluster across x86–64 and ppc64le platforms, and I need the Filebeat Docker image since I run the Elastic stack for log management. However, there is no official Docker image provided on ppc64le architecture, thus I have to build it myself.

Here is how to do it on a Red Hat Enterprise Linux 7.6 server running on ppc64le platform.

Install the necessary software packages.

yum install -y golang make git

Prepare the required environment.

mkdir go
export GOPATH=$(pwd)/go
mkdir -p ${GOPATH}/src/
cd ${GOPATH}/src/

Clone the Git repository of Elastic Beats.

git clone

Checkout the desired…

You may have application running inside OpenShift Container Platform, and that uses a Persistent Volume provisioned from vSphere VMDK. One day, when you find the disk becoming full and nothing could be cleaned up, the problem arise. How to directly expand the volume without losing any data?

Suppose you have a Deployment called MyApp , with PVC MyApp-pvc and PV MyApp-pv , here is how to expand the storage.

Step 1) Stop the application

Stop the application by scaling down the deployment to 0 replicas:

oc scale deploy MyApp --replicas=0

Step 2) Identify the VMDK file of the Persistent Volume

Use below command to get the name of the VMDK disk including its path.


Recently, I need to help a customer to migrate the persistent storage of Image Registry for the OpenShift Container Platform cluster from VMDK block disk to NFS storage.

Here are the steps that I have used to complete the migration.

Step 1) Stop the Image Registry service

Check that Image Registry is currently running with 1 replica.

$ oc get pods -n openshift-image-registry -ldocker-registry=default -o wide
image-registry-6886f79486-sr8lf 1/1 Running 0 14d <none> <none>

Stop the Image Registry by scaling it to 0 replica.

oc patch --patch '{"spec":{"replicas":0}}' --type=merge

Verify that no more Image…

There were a few times the error “cudaErrorInitializationError with exit code 3” was hit when our team run CUDA application inside Docker container. (Depending on your code, you may see the error message “initialization error” instead.)

cudaErrorInitializationError with exit code 3 when running CUDA sample application “nvgraph_Pagerank”

However, if we check the system, nothing strange could be found. Moreover, nvidia-smi gives a normal output, both in the host and inside the container:

Recently I have to setup the Metering Operator inside a OpenShift cluster in order to collect usage data. The environment doesn’t offer any storage provisioner and static NFS provisioning is the only option.

Install the Metering Operator

Prepare the namespace-openshift-metering.yaml YAML file for namespace creation:

apiVersion: v1
kind: Namespace
name: openshift-metering
annotations: ""
labels: "true"

Create openshift-metering namespace:

$ oc create -f namespace-openshift-metering.yaml
namespace/openshift-metering created

Then install Metering Operator using OpenShift Container Platform web console:

Not long ago, I was required to setup a pair of Highly Available NFS Cluster with disk encryption. I turned out setting up the cluster using:

A) Preparations

Setup two CentOS 8 Stream VMs. In this article, each VM will have two disks named /dev/sda and /dev/sdb , they will be the OS disk and Data disk respectively. The hostname and IP address of the environment are:

B) Setup Disk Encryption

Step 1: Encrypt the data disk

Encrypt the data disk using cryptsetup command. You need to…

Edmond Chan

Infrastructure Architect experienced in design and implementation of IT solutions for enterprises

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store