envoy-proxy

Envoy Proxy

We use envoy to have another reverse proxy after NGINX in our Unguard family.

If you want to develop this isolated from the rest of Unguard, do the following:

docker build -t envoy-proxy .
docker run -it -p 8080:8080 envoy-proxy

Health endpoint

There is a custom health endpoint that can be used to check the availability of internal services.

curl -I http://unguard.kube/healthz?path=unguard-microblog-service

Dynamic configuration

The proxy has a mix of static and dynamic configuration.

• The listener_static on port 8080 routes to other Unguard services.
• The listener_dynamic on port 8081 is dynamically configured by the file contents in listener-ds.yaml. Right now, it provides the health endpoint.

The dynamic configuration can be changed at runtime. Just modify listener-ds.yaml in /etc/envoy/unguard. After modifying the file, temporarily move it, because Envoy only watches for file moves and no content changes.

mv /etc/envoy/unguard/listener-ds.yaml /etc/envoy/unguard/listener-ds.bak.yaml
mv /etc/envoy/unguard/listener-ds.bak.yaml /etc/envoy/unguard/listener-ds.yaml