New Post: "An established connection was aborted by the software in your host machine." after establishing a SSH connection to a juniper firewall

Thanks for the reply,
well, I found a solution... the command itself was not the problem, but using the RunCommand() method was so. Instead of the RunCommand() method I used the shellstream example from https://sshnet.codeplex.com/discussions/348421 and now it works!

using System;
using System.IO;
using System.Threading;
using Renci.SshNet;
 
namespace ConsoleApplications
{
    public class Program
    {
        private static System.ComponentModel.IContainer components;
 
        private static void Main(string[] args)
        {
            using (var client = new SshClient(host, "admin", "abc"))
            {
                client.Connect();
 
                using (var stream = client.CreateShellStream("dumb", 80, 24, 800, 600, 1024))
                {
                    var reader = new StreamReader(stream);
                    var writer = new StreamWriter(stream);
                    writer.AutoFlush = true;
 
                    while (stream.Length == 0)
                    {
                        Thread.Sleep(500);
                    }
                    ReadStream(reader);
 
                    WriteStream("show run", writer, stream);
                    ReadStream(reader);
 
                    WriteStream("show ver", writer, stream);
                    ReadStream(reader);
                }
 
                client.Disconnect();
            }
        }
 
        private static void ReadStream(StreamReader reader)
        {
            string line = reader.ReadLine();
            while (line != null)
            {
                Console.WriteLine(line);
                line = reader.ReadLine();
            }
        }
 
        private static void WriteStream(string cmd, StreamWriter writer, ShellStream stream)
        {
            writer.WriteLine(cmd);
            while (stream.Length == 0)
            {
                Thread.Sleep(500);
            }
        }
    }
}