The gRPC Agent has the following guideline and limitation:

• gRPC does not support enhanced Role-Based Access Control (RBAC) as specified in RFC 6536. Only users with a "network-admin" role are granted access to the gRPC agent.

The gRPC Agent exports the supported operations and data structures in the proto definition file at /opt/mtx/etc/nxos_grpc.proto. The file is included in the gRPC Agent RPM. The following shows the definitions:

// Copyright 2016, Cisco Systems Inc.
// All rights reserved.

syntax = "proto3";

package NXOSExtensibleManagabilityService;

// Service provided by Cisco NX-OS gRPC Agent
service gRPCConfigOper {

    // Retrieves the specified YANG configuration data subset from the
    // source datastore
    rpc GetConfig(GetConfigArgs) returns(stream GetConfigReply) {};

    // Retrieves the specified YANG operational data from the source datastore
    rpc GetOper(GetOperArgs) returns(stream GetOperReply) {};

    // Retrieves the specified YANG configuration and operational data
    // subset from the source datastore
    rpc Get(GetArgs) returns(stream GetReply){};

    // Writes the specified YANG data subset to the target datastore
    rpc EditConfig(EditConfigArgs) returns(EditConfigReply) {};

    // Starts a new session between the client and server and acquires a
    // unique session ID
    rpc StartSession(SessionArgs) returns(SessionReply) {};

    // Requests graceful termination of a session
    rpc CloseSession(CloseSessionArgs) returns (CloseSessionReply) {};

    // Forces the termination of a session
    rpc KillSession(KillArgs) returns(KillReply) {};

// Unsupported; reserved for future
    rpc DeleteConfig(DeleteConfigArgs) returns(DeleteConfigReply) {};

    // Unsupported; reserved for future
    rpc CopyConfig(CopyConfigArgs) returns(CopyConfigReply) {};

    // Unsupported; reserved for future
    rpc Lock(LockArgs) returns(LockReply) {};

    // Unsupported; reserved for future
    rpc UnLock(UnLockArgs) returns(UnLockReply) {};

    // Unsupported; reserved for future
    rpc Commit(CommitArgs) returns(CommitReply) {};

    // Unsupported; reserved for future
    rpc Validate(ValidateArgs) returns(ValidateReply) {};

    // Unsupported; reserved for future
    rpc Abort(AbortArgs) returns(AbortReply) {};

}

message GetConfigArgs
{
    // JSON-encoded YANG data to be retrieved
    string YangPath = 1;

    // (Optional) Specifies the request ID.  Default value is 0.
    int64 ReqID = 2;

    // (Optional) Specifies the source datastore; only "running" is supported.
    // Default is "running".
    string Source = 3;
}

message GetConfigReply
{
    // The request ID specified in the request.
    int64 ReqID = 1;

    // JSON-encoded YANG data that was retrieved
    string YangData = 2;

    // JSON-encoded error information when request fails
    string Errors = 3;
}

message GetOperArgs
{
    // JSON-encoded YANG data to be retrieved
    string YangPath = 1;

    // (Optional) Specifies the request ID.  Default value is 0.
    int64 ReqID = 2;
}

message GetOperReply
{
    // The request ID specified in the request.
    int64 ReqID = 1;

    // JSON-encoded YANG data that was retrieved
    string YangData = 2;

    // JSON-encoded error information when request fails
    string Errors = 3;
}

message GetArgs
{
    // JSON-encoded YANG data to be retrieved
    string YangPath=1;

    // (Optional) Specifies the request ID.  Default value is 0.
    int64 ReqID = 2;
}

message GetReply
{
    // The request ID specified in the request.
    int64 ReqID = 1;

    // JSON-encoded YANG data that was retrieved
    string YangData = 2;

    // JSON-encoded error information when request fails
    string Errors = 3;
}

message EditConfigArgs
{
    // JSON-encoded YANG data to be edited
    string YangPath = 1;

    // Specifies the operation to perform on teh configuration datastore with
    // the YangPath data.  Possible values are:
    //   create
    //   merge
    //   replace
    //   delete
    //   remove
    // If not specified, default value is "merge".
    string Operation = 2;

    // A unique session ID acquired from a call to StartSession().
    // For stateless operation, this value should be set to 0.
    int64 SessionID = 3;

    // (Optional) Specifies the request ID.  Default value is 0.
    int64 ReqID = 4;

    // (Optional) Specifies the target datastore; only "running" is supported.
    // Default is "running".
    string Target = 5;

    // Specifies the default operation on the given object while traversing
    // the configuration tree.
    // The following operations are possible:
    //   merge:     merges the configuration data with the target datastore;
    //              this is the default.
    //   replace:   replaces the configuration data with the target datastore.
    //   none:      target datastore is unaffected during the traversal until
    //              the specified object is reached.
    string DefOp = 6;

    // Specifies the action to be performed in the event of an error during
    // configuration.  Possible values are:
    //   stop
    //   roll-back
    //   continue
    // Default is "roll-back".
    string ErrorOp = 7;
}

message EditConfigReply
{
    // The request ID specified in the request.
    int64 ReqID = 1;

    // If EditConfig is successful, YangData contains a JSON-encoded "ok" response.
    string YangData = 2;

    // JSON-encoded error information when request fails
    string Errors = 3;
}

message DeleteConfigArgs
{
    // A unique session ID acquired from a call to StartSession().
    // For stateless operation, this value should be set to 0.
    int64 SessionID = 1;

    // (Optional) Specifies the request ID.  Default value is 0.
    int64 ReqID = 2;

    // (Optional) Specifies the target datastore; only "running" is supported.
    // Default is "running".
    string Target = 3;
}

message DeleteConfigReply
{
    // The request ID specified in the request.
    int64 ReqID = 1;

    // If DeleteConfig is successful, YangData contains a JSON-encoded "ok" response.
    string YangData = 2;

    // JSON-encoded error information when request fails
    string Errors = 3;
}

message CopyConfigArgs
{
    // A unique session ID acquired from a call to StartSession().
    // For stateless operation, this value should be set to 0.
    int64 SessionID = 1;

    // (Optional) Specifies the request ID.  Default value is 0.
    int64 ReqID = 2;

    // (Optional) Specifies the source datastore; only "running" is supported.
    // Default is "running".
    string Source = 3;

    // (Optional) Specifies the target datastore; only "running" is supported.
    // Default is "running".
    string Target = 4;
}

message CopyConfigReply
{
    // The request ID specified in the request.
    int64 ReqID = 1;

    // If CopyConfig is successful, YangData contains a JSON-encoded "ok" response.
    string YangData = 2;

    // JSON-encoded error information when request fails
    string Errors = 3;
}

message LockArgs
{
    // A unique session ID acquired from a call to StartSession().
    int64 SessionID = 1;

    // (Optional) Specifies the request ID.  Default value is 0.
    int64 ReqID=2;

    // (Optional) Specifies the target datastore; only "running" is supported.
    // Default is "running".
    string Target = 3;
}

message LockReply
{
    // The request ID specified in the request.
    int64 ReqID = 1;

    // If Lock is successful, YangData contains a JSON-encoded "ok" response.
    string YangData = 2;

    // JSON-encoded error information when request fails
    string Errors = 3;
}

message UnLockArgs
{
    // A unique session ID acquired from a call to StartSession().
    int64 SessionID = 1;

    // (Optional) Specifies the request ID.  Default value is 0.
    int64 ReqID = 2;

    // (Optional) Specifies the target datastore; only "running" is supported.
    // Default is "running".
    string Target = 3;
}

message UnLockReply
{
    // The request ID specified in the request.
    int64 ReqID = 1;

    // If UnLock is successful, YangData contains a JSON-encoded "ok" response.
    string YangData = 2;

    // JSON-encoded error information when request fails
    string Errors = 3;
}

message SessionArgs
{
    // (Optional) Specifies the request ID.  Default value is 0.
    int64 ReqID = 1;
}

message SessionReply
{
    // The request ID specified in the request.
    int64 ReqID = 1;
    int64 SessionID = 2;

    // JSON-encoded error information when request fails
    string Errors = 3;
}

message CloseSessionArgs
{
    // (Optional) Specifies the request ID.  Default value is 0.
    int64 ReqID = 1;

    // A unique session ID acquired from a call to StartSession().
    int64 SessionID = 2;
}

message CloseSessionReply
{
    // The request ID specified in the request.
    int64 ReqID = 1;

    // If CloseSession is successful, YangData contains a JSON-encoded "ok" response.
    string YangData = 2;

    // JSON-encoded error information when request fails
    string Errors = 3;
}

message KillArgs
{
    // A unique session ID acquired from a call to StartSession().
    int64 SessionID = 1;

    int64 SessionIDToKill = 2;

    // (Optional) Specifies the request ID.  Default value is 0.
    int64 ReqID = 3;
}

message KillReply
{
    // The request ID specified in the request.
    int64 ReqID = 1;

    // If Kill is successful, YangData contains a JSON-encoded "ok" response.
    string YangData = 2;

    // JSON-encoded error information when request fails
    string Errors = 3;
}

message ValidateArgs
{
    // A unique session ID acquired from a call to StartSession().
    int64 SessionID = 1;

    // (Optional) Specifies the request ID.  Default value is 0.
    int64 ReqID = 2;
}

message ValidateReply
{
    // The request ID specified in the request.
    int64 ReqID = 1;

    // If Validate is successful, YangData contains a JSON-encoded "ok" response.
    string YangData = 2;

    // JSON-encoded error information when request fails
    string Errors = 3;
}

message CommitArgs
{
    // A unique session ID acquired from a call to StartSession().
    int64 SessionID = 1;

    // (Optional) Specifies the request ID.  Default value is 0.
    int64 ReqID = 2;
}

message CommitReply
{
    // (Optional) Specifies the request ID.  Default value is 0.
    int64 ReqID = 1;

    // If Commit is successful, YangData contains a JSON-encoded "ok" response.
    string YangData = 2;

    // JSON-encoded error information when request fails
    string Errors = 3;
}

message AbortArgs
{
    // A unique session ID acquired from a call to StartSession().
    int64 SessionID = 1;

    // (Optional) Specifies the request ID.  Default value is 0.
    int64 ReqID = 2;
}

message AbortReply
{
    // (Optional) Specifies the request ID.  Default value is 0.
    int64 ReqID = 1;

    // If Abort is successful, YangData contains a JSON-encoded "ok" response.
    string YangData = 2;

    // JSON-encoded error information when request fails
    string Errors = 3;
}