Questions tagged [etcd]

etcd is a highly-available key value store for shared configuration and service discovery, inspired by Apache ZooKeeper and doozer.

etcd is a highly-available key value store for shared configuration and service discovery, inspired by Apache ZooKeeper and doozer, with a focus on being:

  • Simple: curl'able user facing API (HTTP+JSON)
  • Secure: optional SSL client cert authentication
  • Fast: benchmarked 1000s of writes/s per instance
  • Reliable: properly distributed using Raft

etcd is written in Go and uses the Raft consensus algorithm to manage a highly-available replicated log.

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Using etcd as primary store/database?

Can etcd be used as reliable database replacement? Since it is distributed and stores key/value pairs in a persistent way, it would be a great alternative nosql database. In addition, it has a great API. Can someone explain why this is not a thing?
Plus Ultra
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Why bother with service discovery when message oriented middleware does the job?

I get the problem that etcd/consul/$whatever are trying to solve. Service consumers need to talk to service providers, a hugely fluid distributed system needs a mechanism to marry the two. However, the problem of "where do service consumers go with…
Susan Barr
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How to configure dynamic properties while using spring boot?

I'm planning to use Spring Boot for my assignment. Its a typical server application with connection to database. I know I can use Spring Configuration to externalize my properties e.g. db connection details. But I also have other dynamic properties…
eton dolittle
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How to access kubernetes keys in etcd

Question How to get the Kubernetes related keys from etcd? Tried to list keys in etcd but could not see related keys. Also where is etcdctl installed? $ etcdctl bash: etcdctl: command not found.. $ sudo netstat -tnlp Active Internet connections…
mon
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Automatic self-configuration of an etcd cluster as a Docker swarm service

I want to find a way to deploy an etcd cluster as a Docker Swarm service that would automatically configure itself without any interaction. Basically, I think of something in spirit of this command: docker service create --name etcd --replicas 3…
drdaeman
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Hazelcast (Java) and ETCD (golang) differences/similarities?

Now we building a realtime analytics system and it should be highly distributed. We plan to use distributed locks and counters to ensure data consistency, and we need a some kind of distributed map to know which client is connected to which…
The Architect
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docker-swarm and docker-compose how to dynamically add nodes and have them resolvable by the services

I have been playing with docker-compose and have cobbled together a project from the docker hub website. One thing that eludes me is how I can scale individual services up (by adding more instances) AND have existing instances somehow made aware of…
bryan hunt
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Is it safe to use etcd across multiple data centers?

Is it safe to use etcd across multiple data centers? As it expose etcd port to public internet. Do I have to use client certificates in this case or etcd has some sort of authification?
Alex Yusupov
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Where does ConfigMap data gets stored?

I created ConfigMap using kubectl and I can also see it using: kubectl get cm I am just curious where kubernetes stores this data/information within the cluster? Does it store in etc? How do I view it, if it stored in etcd? Does it store in any…
Ramesh
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Leader election with: Etcd vs Zookeeper vs Hazelcast

We are choosing the best option for implementing a leader election for our service (written in Java) comprised of multiple (e.g., 3) instances for high availability. Our goal is to have only a single instance active at any given time. Would be great…
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etcdctl throws Error: context deadline exceeded error

I'm trying to create a one node etcd cluster on AWS using coreos cloud-config. I have created a Route53 recordset with value etcd.uday.com which has a alias to the ELB which points to the ec2 instance. Etcd is running successfully but when I run the…
Udaykiran R
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Systemd string escaping

If I run this command /bin/bash -c 'while true;do /usr/bin/etcdctl set my-container "{\"host\": \"1\", \"port\": $(/usr/bin/docker port my-container 5000 | cut -d":" -f2)}" --ttl 60;sleep 45;done' I get back from etcd what I expect {"host":"1",…
MParker
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how do I get etcd values into my systemd service on coreOS?

I have two services A and B. A sets a value in etcd as it's being started, say the public IP address which it gets from an environment file: ExecStartPost=/usr/bin/etcdctl set /A_ADDR $COREOS_PUBLIC_IPV4 B needs that value as it starts up, as well…
Mike Dewar
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Kubernetes object size limitations

I am dealing with CRDs and creating Custom resources. I need to keep lots of information about my application in the Custom resource. As per the official doc, etcd works with request up to 1.5MB. I am hitting errors something like "error": "Request…
Yudi
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ELI5: How etcd really works and what is consensus algorithm

I am having hard time to grab what etcd (in CoreOS) really does, because all those "distributed key-value storage" thingy seems intangible to me. Further reading into etcd, it delves into into Raft consensus algorithm, and then it becomes really…
Aizan Fahri
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