51 lines
1.3 KiB
Terraform
51 lines
1.3 KiB
Terraform
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# Tune etcd for reduced disk writes on k8s-master.
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# Increases snapshot-count from 10000 (default) to 50000 to reduce WAL snapshot frequency.
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# etcd writes ~37.5 GB/day; less frequent snapshots reduce this by ~30-40%.
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# This patches the kubeadm-managed static pod manifest. Note: kubeadm upgrades
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# will reset this, so re-apply after any kubeadm upgrade.
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resource "null_resource" "etcd_tuning" {
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connection {
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type = "ssh"
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user = "wizard"
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host = var.k8s_master_host
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private_key = var.ssh_private_key
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}
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provisioner "remote-exec" {
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inline = [
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<<-SCRIPT
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sudo python3 -c "
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import yaml
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path = '/etc/kubernetes/manifests/etcd.yaml'
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with open(path) as f:
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doc = yaml.safe_load(f)
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container = doc['spec']['containers'][0]
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args = container['command']
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# Update or add --snapshot-count=50000
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new_args = [a for a in args if not a.startswith('--snapshot-count=')]
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new_args.append('--snapshot-count=50000')
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# Update or add --quota-backend-bytes (256MB, default is 2GB which is fine)
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# Keep default for now
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container['command'] = new_args
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with open(path, 'w') as f:
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yaml.dump(doc, f, default_flow_style=False)
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print('etcd manifest updated: --snapshot-count=50000')
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"
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SCRIPT
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]
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}
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# Re-run if the configuration changes
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triggers = {
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snapshot_count = "50000"
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}
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}
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