Tag: kubernetes

Container watches etcd leader vs container watches etcd cluster

My containerized application requires dynamic notification of changes to configuration data held by etcd. Assuming a clustered etcd implementation, my app would ideally access (and watch) the etcd leader. I could discover the etcd leader prior to launching my app (and include the leader’s IP in my app’s environment), as suggested here, but the leader […]

RestTemplate exchange call gives 503 error when running in Docker container at Kubernetes environment

My Spring Boot application runs fine when I run on the server as traditional way. But, when I create a Docker image with this app and run the container at Kubernetes environment, I get “503 Service Unavailable” error back when the app makes RestTemplate call. Here is the code snipped where the call is made: […]

Kubernetes hyperkube config cannot found

Started using Kubernetes for a project for work, its been alot of headache, I finally got it working. Not sure its the best way to to get it running, but im basically running hyperkube via docker. My config looks like this sudo docker run \ –volume=/:/rootfs:ro \ –volume=/sys:/sys:ro \ –volume=/dev:/dev \ –volume=/var/lib/docker/:/var/lib/docker:rw \ –volume=/var/lib/kubelet/:/var/lib/kubelet:rw \ […]

Openshift PaaS/Kubernetes Docker Container Monitoring and Orchestration

Kubernetes deployment and replication controller give the ability to self heal by ensuring a minimum number of replicas is/are present. Also the auto scaling features, allows to increase replicas given a specific cpu threshold. Are there tools available that would provide flexibility in the auto-healing and auto-scale features? Example : Auto-adjust number of replicas during […]

How to setup dns alias for a service running in Kubernetes

I have separate pods running that need to be able to find each other, and we have some legacy configurations out on external clients. Previously all of our systems were configured to find their dependencies on the intranet via hostnames that included dots (.) in the names. Such as HDFS.NAMENODE HDFS.DATANODE While we can work […]

java.net.UnknownHostException in pid 1 for address resolved by kube-dns

I am receiving an java.net.UnknownHostException: postgres-service on a machine where I can ping postgres-service on the command line. This is in the context of Kubernetes (more specifically GKE) services and Docker images. Could it be that Java requires additional packages (in comparison to ping) to be installed before it can resolve symbolic IP addresses such […]

Why use Consul with Kubernetes, Docker, Mesos?

Most container services have some sort of built in service discovery mechanism. So why is it that someone would still incorporate Consul into their setup? I know that Consul provides other benefits besides service discovery, such as K/V store, Consul templates, and service monitoring, however none of these seem like a big enough benefit.

Understanding Kubernetes resource requests

We are having trouble understanding Kubernetes resource requests. We run a cluster of 3x 1CPU / 3.75Gb Our issue is this: We are allocating really small CPU requests to each container in our pods so the pod will be scheduled onto a node. Our containers are basically all web containers running NodeJS or PHP so […]

Kubernetes Kube-Proxy Server: Can it run without iptables' nat module?

Background: In our environment, iptables‘ nat module is disabled. So I must use ‘-b=none –iptables=false’ to start docker daemon and always add ‘–net host’ when using ‘docker run’ command. The same problem arising when using kubernetes. When I try to start the ‘kube-proxy’ service, I got an error: > F0822 14:32:49.065506 29630 server.go:101] Unable to […]

Apache Marathon: Pod/Compose like?

In Apache Marathon, is there way to specify multiple containers as a single/logical application as you can do in Kubernetes’ pod and Docker’s compose?

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