42 lines
1.6 KiB
Markdown
42 lines
1.6 KiB
Markdown
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# Waiting for Servers to be Provisioned and Ready
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## Overview
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Often when working with automated deployments you will want to wait for your servers to be provisioned and ready before running your Ansible playbook. This is a simple bash script you can run before your Ansible playbook to wait for your servers to be ready.
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## The Script
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The script below assumes a few things, namely:
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* You have a private key file called `private.key` in the root directory of your project
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* You have a terraform directory in the root of your project
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* You have two IP address outputs in your terraform called `server-1-ip-address` and `server-2-ip-address`
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```bash [wait-for-servers.sh]
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# Simple script to wait till all the servers are up and running (e.g. not setting up)
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echo 'Trying SSH to new instances, checking cloud-init status... (It will say "Connection refused" until it is ready.)'
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# 6 retries x 5 seconds each = maximum approx 30 seconds to wait for SSH, then bail.
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check_instances() {
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echo now checking...
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ssh root@"$server_1_ip" -o StrictHostKeyChecking=no -i private.key cloud-init status -w
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ssh root@"$server_2_ip" -o StrictHostKeyChecking=no -i private.key cloud-init status -w
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}
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echo getting hostnames...
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# Navigate to terraform directory
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cd terraform
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server_1_ip="$(terraform output -raw server-1-ip-address)"
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server_2_ip="$(terraform output -raw server-2-ip-address)"
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# Navigate back to root directory
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cd ..
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timeout=6
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stopwatch=0
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until check_instances; do
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stopwatch=$((stopwatch+1))
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if [[ $stopwatch -ge $timeout ]]; then echo Error: Timed out waiting for instance; exit -1; fi
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sleep 5
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done
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```
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