IBM Cloud has made a massive shift to Kubernetes. From an initial plan for a hosted Kubernetes public cloud offering it has snowballed to tens of thousands of production Kubernetes clusters running across more than 60 data centers around the globe, hosting 90% of the PaaS and SaaS services offered by IBM Cloud. I spoke with Dan Berg, IBM Distinguished Engineer, to find out more about their journey, what triggered such a significant shift, and what they learned along the way.

When learning a new technology like Istio, it’s always a good idea to take a look at sample apps. Istio repo has a few sample apps but they fall short in various ways. BookInfo is covered in the docs and it is a good first step. However, it is too verbose with too many services for me and the docs seem to focus on managing the BookInfo app, rather than building it from ground up. There’s a smaller helloworld sample but it’s more about autoscaling than anything else.

AquaSec’s Daniel Sagi recently authored a blog post about DNS spoofing in Kubernetes. TLDR is that if you use default networking in Kubernetes you might be vulnerable to ARP spoofing which can allow pods to spoof (impersonate) the IP addresses of other pods. Since so much traffic is dialed via domain names rather than IPs, spoofing DNS can allow you to redirect lots of traffic inside the cluster for nefarious purposes.