COREDNS-GRPC_SERVER(7)

NAME

grpc_server - configures DNS-over-gRPC server options.

DESCRIPTION

The grpc_server plugin allows you to configure parameters for the DNS-over-gRPC server to fine-tune the security posture and performance of the server.

This plugin can only be used once per gRPC listener block.

SYNTAX

    grpc_server {
        max_streams POSITIVE_INTEGER
        max_connections POSITIVE_INTEGER
    }

•   max_streams limits the number of concurrent gRPC streams per connection. This helps prevent unbounded streams on a single connection, exhausting server resources. The default value is 256 if not specified. Set to 0 for unbounded.

•   max_connections limits the number of concurrent TCP connections to the gRPC server. The default value is 200 if not specified. Set to 0 for unbounded.

EXAMPLES

Set custom limits for maximum streams and connections:

    grpc://.:8053 {
        tls cert.pem key.pem
        grpc_server {
            max_streams 50
            max_connections 100
        }
        whoami
    }

Set values to 0 for unbounded, matching CoreDNS behaviour before v1.14.0:

    grpc://.:8053 {
        tls cert.pem key.pem
        grpc_server {
            max_streams 0
            max_connections 0
        }
        whoami
    }