skywalking-java/docs/en/setup/backend/grpc-ssl.md

Support gRPC SSL transportation for OAP server

For OAP communication we are currently using gRPC, a multi-platform RPC framework that uses protocol buffers for message serialization. The nice part about gRPC is that it promotes the use of SSL/TLS to authenticate and encrypt exchanges. Now OAP supports to enable SSL transportation for gRPC receivers.

You can follow below steps to enable this feature

Creating SSL/TLS Certificates

It seems like step one is to generate certificates and key files for encrypting communication. I thought this would be fairly straightforward using openssl from the command line.

Use this script if you are not familiar with how to generate key files.

We need below files:

• server.pem a private RSA key to sign and authenticate the public key. It's either a PKCS#8(PEM) or PKCS#1(DER).
• server.crt self-signed X.509 public keys for distribution.
• ca.crt a certificate authority public key for a client to validate the server's certificate.

Config OAP server

You can enable gRPC SSL by add following lines to application.yml/core/default.

gRPCSslEnabled: true
gRPCSslKeyPath: /path/to/server.pem
gRPCSslCertChainPath: /path/to/server.crt
gRPCSslTrustedCAPath: /path/to/ca.crt

gRPCSslKeyPath and gRPCSslCertChainPath are loaded by OAP server to encrypt the communication. gRPCSslTrustedCAPath helps gRPC client to verify server certificates in cluster mode.

When new files are in place, they can be load dynamically instead of restarting OAP instance.

If you enable sharding-server to ingest data from external, add following lines to application.yml/receiver-sharing-server/default:

gRPCSslEnabled: true
gRPCSslKeyPath: /path/to/server.pem
gRPCSslCertChainPath: /path/to/server.crt

Because sharding-server only receives data from external, so it doesn't need CA at all.

If you port to java agent, refer to TLS.md to config java agent to enable TLS.