coredns/man/coredns-tls.7

.\" generated with Ronn/v0.7.3
.\" http://github.com/rtomayko/ronn/tree/0.7.3
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.TH "COREDNS\-TLS" "7" "October 2018" "CoreDNS" "CoreDNS plugins"
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.SH "NAME"
\fItls\fR \- allows you to configure the server certificates for the TLS and gRPC servers\.
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.SH "DESCRIPTION"
CoreDNS supports queries that are encrypted using TLS (DNS over Transport Layer Security, RFC 7858) or are using gRPC (https://grpc\.io/, not an IETF standard)\. Normally DNS traffic isn\'t encrypted at all (DNSSEC only signs resource records)\.
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.P
The \fIproxy\fR plugin also support gRPC (\fBprotocol gRPC\fR), meaning you can chain CoreDNS servers using this protocol\.
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.P
The \fItls\fR "plugin" allows you to configure the cryptographic keys that are needed for both DNS\-over\-TLS and DNS\-over\-gRPC\. If the \fBtls\fR directive is omitted, then no encryption takes place\.
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.P
The gRPC protobuffer is defined in \fBpb/dns\.proto\fR\. It defines the proto as a simple wrapper for the wire data of a DNS message\.
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.SH "SYNTAX"
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.nf

tls CERT KEY [CA]
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.fi
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.P
Parameter CA is optional\. If not set, system CAs can be used to verify the client certificate
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.SH "EXAMPLES"
Start a DNS\-over\-TLS server that picks up incoming DNS\-over\-TLS queries on port 5553 and uses the nameservers defined in \fB/etc/resolv\.conf\fR to resolve the query\. This proxy path uses plain old DNS\.
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.IP "" 4
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.nf

tls://\.:5553 {
    tls cert\.pem key\.pem ca\.pem
    proxy \. /etc/resolv\.conf
}
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.fi
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.IP "" 0
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.P
Start a DNS\-over\-gRPC server that is similar to the previous example, but using DNS\-over\-gRPC for incoming queries\.
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.IP "" 4
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.nf

grpc://\. {
    tls cert\.pem key\.pem ca\.pem
    proxy \. /etc/resolv\.conf
}
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.fi
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.IP "" 0
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.P
Only Knot DNS\' \fBkdig\fR supports DNS\-over\-TLS queries, no command line client supports gRPC making debugging these transports harder than it should be\.
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.SH "ALSO SEE"
RFC 7858 and https://grpc\.io\.