Issuing a single command from a cluster of servers?

Question

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 make sure that this command is only emitted once every ten minutes. I ran into the issue that I cannot just add a crontab to my servers unless I want them all to emit every X minutes.

I started looking at using HashiCorp Consul as its fairly highly available and seemingly easier than etcd or Zookeeper. I do not know how to actually create something that will do this though.

I will be using this script on all servers

#!/bin/bash

curl -i -H "Accept: application/json" \
-H "Content-Type:application/json"    \
-X POST --data '{"status":"ruok"}' "https://foobar.com/status"

So how would I write Consul in order to run this once in a pool of nodes?

Something like [this](https://github.com/EvanKrall/cronsul)? I just searched Google now for "distributed cron using consul"... — Florin Asăvoaie, Feb 15 '16 at 19:39
@FlorinAsăvoaie that works great, please post as an answer so I can accept =) — ehime, Feb 16 '16 at 19:19

score 1 · Accepted Answer · answered Feb 16 '16 at 20:11

1

You could use this.

Just Googled "distributed cron using consul".

answered Feb 16 '16 at 20:11

Florin Asăvoaie

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Issuing a single command from a cluster of servers?

1 Answers1