Questions tagged [etcd]

A highly-available key value store for shared configuration and service discovery

etcd is a distributed key value store that provides a reliable way to store data across a cluster of machines. It’s open-source and available on GitHub. etcd gracefully handles master elections during network partitions and will tolerate machine failure, including the master.

Your applications can read and write data into etcd. A simple use-case is to store database connection details or feature flags in etcd as key value pairs. These values can be watched, allowing your app to reconfigure itself when they change.

Advanced uses take advantage of the consistency guarantees to implement database master elections or do distributed locking across a cluster of workers.

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Kubernetes - kubeadm join - Connection refused after new control plane joined

Issue I am trying to join a second control-plane node to a K8S cluster. The first node has a IP of 10.1.50.4 where the second node has a IP of 10.1.50.5. There is a load balancer Virtual IP for the control-plane nodes of 10.1.50.250. K8S Version:…
Pie
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k3s without HA: how to switch master node?

Rancher documentation on k3s is quite nice and its HA support (both with external DB or embedded etcd) look nice, but I don't want/need an HA setup. In case my master node fails, I don't mind having downtime while I re-create it or make a master out…
Filipe Pina
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Why do kubernetes kube-api server need etcd-keyfile and kubelet-client-key

As I understand kube-api server acts as a client when communicating with ETCD and Kubelet. Both ETCD and Kubelet act as servers for kube-api. With secure environment (two way SSL authentication), kube-api server needs the ETCD and Kubelet…
srinu259
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Etcd: machines can't connect to cluster

I reconfigurated my etcd cluster for working with certificates and now when i trying to start i'm getting First machine: Nov 05 16:24:43 Dm3Ch-Server-Node1 etcd[13999]: 21b9ef35413b514 received vote from 21b9ef35413b514 at term 493 Nov 05 16:24:43…
Dm3Ch
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"EtcdException: Could not get the list of servers" while running calico rkt container on coreos

I have two coreos stable v1122.2.0 machines, each one with etcd2 configured with tls. I created the certificates using https://github.com/coreos/etcd/tree/master/hack/tls-setup. now I'm trying to configure calico-node to operate on my coreos master…
ufk
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Multiple Core-OS clusters with a single etcd cluster?

Is it possible to create different core os clusters all linked up to 1 etcd cluster ? If yes, how ? I have a scenario where I need to create multiple clusters but I want to keep one etcd cluster. Currently I end up having all instances in the same…
Hazim
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SSH fails on CoreOS when substituting etcd cloud-config variables

I have a minimal cloud-config that works without problems on DigitalOcean. I added some hardening for SSH, which requires restarting sshd.socket to become effective: units: - name: sshd.socket command: restart Adding this unit alone (no…
Rolf W.
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Does a CoreOS member need to have a public ip to join an etcd2 cluster?

I am starting 5 coreos EC2 members all in a private subnet. Then assign one elastic ip to one of the members. It seems that only that one with an ip assigned can join the etcd2 cluster, and is perpetually waiting for the other 4. here is my…
theRemix
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Issuing a single command from a cluster of servers?

I have a cluster of servers that will be running a simple ruok command with fallover. The command will be something simple like curl -X POST http://foo.com/status. Due to the fact that I will have anywhere from 3 to 300 nodes in this pool, I want to…
ehime
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ETCD fails to start, running CoreOS on AWS,EC2

I use ami-05ffb06f, t2.micro EC2 instance. I use cloud-config to start etcd, but it fails to start Error: client: etcd cluster is unavailable or misconfigured error #0: dial tcp 127.0.0.1:4001: connection refused error #1: dial tcp…
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Kubernetes, flannel and exposing services

I have a kubernetes setup running nicely, but I can't seem to expose services externally. I'm thinking my networking is not set up correctly: kubernetes services addresses: --service-cluster-ip-range=172.16.0.1/16 flannel network config: etcdctl…
jaxxstorm
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Kubernetes service etcd références

If someone with quite good kubernetes's services understanding could confirm me that once you require a new service to be created kubernetes push a reference of it on the etcd database and what is the URL to request it would be wonderful!!!
Dr I
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Configure cloud-config using Azure Powershell 1.0

I have spent some significant time getting an Azure PS script starting up a few CoreOS instances. I have everything working except I have no clue how to get the cloud-config added. Using the CLI, you can do something like: azure vm create…
Dave
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Recover from failed etcd2 / CoreOS cluster

I've got a cluster of 3 CoreOS machines running on Azure. I rebooted two at the same time and the cluster failed as expected. I need to replace the discovery token, cloud-config is read on every bootup, but according to the CoreOS docs: Once an…
Mark
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Removing a stale CoreOS node from discovery.etcd.io

I removed a node from a CoreOS cluster and brought up a fresh one in its place. Unfortunately, it picked up the same IP as the old machine. This stopped etcd from discovering the rest of the cluster, with messages like this in the journal: "failed:…
Paul Dixon
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