Repository: kubernetes-sigs/external-dns (language: go)

Issue:
ETCD TLS support 
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**What would you like to be added**: I'd like to use an existing etcd cluster in order to have external-dns work with coredns

**Why is this needed**: Allows re-using an existing etcd cluster instead of creating a new one. Helps in more resource-constrained environments too, albeit its possible security downsides.

I could send a PR in the next week (hopefully) if this feature is welcome. Could an implementation along the lines of #4503 be accepted? I think the implementation really just needs to pass along some config variables to golang's etcd client.


Discussion / hints:

Fix patch:
diff --git a/docs/tutorials/coredns.md b/docs/tutorials/coredns.md
index bc673494c5..38d8f5b7d4 100644
--- a/docs/tutorials/coredns.md
+++ b/docs/tutorials/coredns.md
@@ -86,7 +86,7 @@ helm install --name my-coredns --values values.yaml stable/coredns
 ## Installing ExternalDNS
 ### Install external ExternalDNS
 ETCD_URLS is configured to etcd client service address.
-Optionnally, you can configure ETCD_USERNAME and ETCD_PASSWORD for authenticating to etcd.
+Optionally, you can configure ETCD_USERNAME and ETCD_PASSWORD for authenticating to etcd. It is also possible to connect to the etcd cluster via HTTPS using the following environment variables: ETCD_CA_FILE, ETCD_CERT_FILE, ETCD_KEY_FILE, ETCD_TLS_SERVER_NAME, ETCD_TLS_INSECURE.
 
 #### Manifest (for clusters without RBAC enabled)
 


Test patch: