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* Add "lb" outbound rule for worker TCP _and_ UDP traffic * Fix Azure worker nodes clock synchronization being inactive due to timeouts reaching the CoreOS / Flatcar NTP pool * Fix Azure worker nodes not providing outbount UDP connectivity Background: Azure provides VMs outbound connectivity either by having a public IP or via an SNAT masquerade feature bundled with their virtual load balancing abstraction (in contrast with, say, a NAT gateway). Azure worker nodes have only a private IP, but are associated with the cluster load balancer's backend pool and ingress frontend IP. Outbound traffic uses SNAT with this frontend IP. A subtle detail with Azure SNAT seems to be that since both inbound lb_rule's are TCP only, outbound UDP traffic isn't SNAT'd (highlights the reasons Azure shouldn't have conflated inbound load balancing with outbound SNAT concepts). However, adding a separate outbound rule and disabling outbound SNAT on our ingress lb_rule's we can tell Azure to continue load balancing as before, and support outbound SNAT for worker traffic of both the TCP and UDP protocol. Fixes clock synchronization timeouts: ``` systemd-timesyncd[786]: Timed out waiting for reply from 45.79.36.123:123 (3.flatcar.pool.ntp.org) ``` Azure controller nodes have their own public IP, so controllers (and etcd) nodes have not had clock synchronization or outbound UDP issues |
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cl | ||
workers | ||
LICENSE | ||
README.md | ||
bootstrap.tf | ||
controllers.tf | ||
lb.tf | ||
network.tf | ||
outputs.tf | ||
security.tf | ||
ssh.tf | ||
variables.tf | ||
versions.tf | ||
workers.tf |
README.md
Typhoon
Typhoon is a minimal and free Kubernetes distribution.
- Minimal, stable base Kubernetes distribution
- Declarative infrastructure and configuration
- Free (freedom and cost) and privacy-respecting
- Practical for labs, datacenters, and clouds
Typhoon distributes upstream Kubernetes, architectural conventions, and cluster addons, much like a GNU/Linux distribution provides the Linux kernel and userspace components.
Features
- Kubernetes v1.18.0 (upstream)
- Single or multi-master, Calico or flannel networking
- On-cluster etcd with TLS, RBAC-enabled, network policy
- Advanced features like worker pools, low-priority workers, and snippets customization
- Ready for Ingress, Prometheus, Grafana, and other optional addons
Docs
Please see the official docs and the Azure tutorial.