diff --git a/dc/m6220-proxy/cli/cli.go b/dc/m6220-proxy/cli/cli.go
new file mode 100644
index 0000000..2e89ca8
--- /dev/null
+++ b/dc/m6220-proxy/cli/cli.go
@@ -0,0 +1,242 @@
+package cli
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"github.com/ziutek/telnet"
+	"golang.org/x/net/trace"
+)
+
+type Client struct {
+	conn *telnet.Conn
+
+	username string
+	password string
+
+	loggedIn       bool
+	promptHostname string
+}
+
+func NewClient(c *telnet.Conn, username, password string) *Client {
+	return &Client{
+		conn:     c,
+		username: username,
+		password: password,
+	}
+}
+
+func (c *Client) readUntil(ctx context.Context, delims ...string) (string, error) {
+	chStr := make(chan string, 1)
+	chErr := make(chan error, 1)
+	go func() {
+		s, err := c.conn.ReadUntil(delims...)
+		if err != nil {
+			chErr <- err
+			return
+		}
+		chStr <- string(s)
+	}()
+
+	select {
+	case <-ctx.Done():
+		return "", fmt.Errorf("context done")
+	case err := <-chErr:
+		c.trace(ctx, "readUntil failed: %v", err)
+		return "", err
+	case s := <-chStr:
+		c.trace(ctx, "readUntil <- %q", s)
+		return s, nil
+
+	}
+}
+
+func (c *Client) readString(ctx context.Context, delim byte) (string, error) {
+	chStr := make(chan string, 1)
+	chErr := make(chan error, 1)
+	go func() {
+		s, err := c.conn.ReadString(delim)
+		if err != nil {
+			chErr <- err
+			return
+		}
+		chStr <- s
+	}()
+
+	select {
+	case <-ctx.Done():
+		return "", fmt.Errorf("context done")
+	case err := <-chErr:
+		c.trace(ctx, "readString failed: %v", err)
+		return "", err
+	case s := <-chStr:
+		c.trace(ctx, "readString <- %q", s)
+		return s, nil
+
+	}
+}
+
+func (c *Client) writeLine(ctx context.Context, s string) error {
+	n, err := c.conn.Write([]byte(s + "\n"))
+	if got, want := n, len(s)+1; got != want {
+		err = fmt.Errorf("wrote %d bytes out of %d", got, want)
+	}
+	if err != nil {
+		c.trace(ctx, "writeLine failed: %v", err)
+		return err
+	}
+	c.trace(ctx, "writeLine -> %q", s)
+	return nil
+}
+
+func (c *Client) trace(ctx context.Context, f string, parts ...interface{}) {
+	tr, ok := trace.FromContext(ctx)
+	if !ok {
+		//fmted := fmt.Sprintf(f, parts...)
+		//glog.Infof("[no trace] %s", fmted)
+		return
+	}
+	tr.LazyPrintf(f, parts...)
+}
+
+func (c *Client) logIn(ctx context.Context) error {
+	if c.loggedIn {
+		return nil
+	}
+
+	// Provide username.
+	prompt, err := c.readString(ctx, ':')
+	if err != nil {
+		return fmt.Errorf("could not read username prompt: %v", err)
+	}
+	if !strings.HasSuffix(prompt, "User:") {
+		return fmt.Errorf("invalid username prompt: %v", err)
+	}
+	if err := c.writeLine(ctx, c.username); err != nil {
+		return fmt.Errorf("could not write username: %v")
+	}
+
+	// Provide password.
+	prompt, err = c.readString(ctx, ':')
+	if err != nil {
+		return fmt.Errorf("could not read password prompt: %v", err)
+	}
+	if !strings.HasSuffix(prompt, "Password:") {
+		return fmt.Errorf("invalid password prompt: %v", err)
+	}
+	if err := c.writeLine(ctx, c.password); err != nil {
+		return fmt.Errorf("could not write password: %v")
+	}
+
+	// Get unprivileged prompt.
+	prompt, err = c.readString(ctx, '>')
+	if err != nil {
+		return fmt.Errorf("could not read unprivileged prompt: %v", err)
+	}
+
+	parts := strings.Split(prompt, "\r\n")
+	c.promptHostname = strings.TrimSuffix(parts[len(parts)-1], ">")
+
+	// Enable privileged mode.
+
+	if err := c.writeLine(ctx, "enable"); err != nil {
+		return fmt.Errorf("could not write enable: %v")
+	}
+
+	// Provide password (again)
+	prompt, err = c.readString(ctx, ':')
+	if err != nil {
+		return fmt.Errorf("could not read password prompt: %v", err)
+	}
+	if !strings.HasSuffix(prompt, "Password:") {
+		return fmt.Errorf("invalid password prompt: %v", err)
+	}
+	if err := c.writeLine(ctx, c.password); err != nil {
+		return fmt.Errorf("could not write password: %v")
+	}
+
+	// Get privileged prompt.
+	prompt, err = c.readString(ctx, '#')
+	if err != nil {
+		return fmt.Errorf("could not read privileged prompt: %v", err)
+	}
+
+	if !strings.HasSuffix(prompt, c.promptHostname+"#") {
+		return fmt.Errorf("unexpected privileged prompt: %v", prompt)
+	}
+
+	// Disable pager.
+	if err := c.writeLine(ctx, "terminal length 0"); err != nil {
+		return fmt.Errorf("could not diable pager: %v", err)
+	}
+	prompt, err = c.readString(ctx, '#')
+	if err != nil {
+		return fmt.Errorf("could not disable pager: %v", err)
+	}
+	if !strings.HasSuffix(prompt, c.promptHostname+"#") {
+		return fmt.Errorf("unexpected privileged prompt: %v", prompt)
+	}
+
+	// Success!
+	c.loggedIn = true
+	c.trace(ctx, "logged into %v", c.promptHostname)
+	return nil
+}
+
+func (c *Client) RunCommand(ctx context.Context, command string) ([]string, string, error) {
+	if err := c.logIn(ctx); err != nil {
+		return nil, "", fmt.Errorf("could not log in: %v", err)
+	}
+
+	// First, synchronize to prompt.
+	attempts := 3
+	for {
+		c.writeLine(ctx, "")
+		line, err := c.readString(ctx, '\n')
+		if err != nil {
+			return nil, "", fmt.Errorf("while synchronizing to prompt: %v", err)
+		}
+		line = strings.Trim(line, "\r\n")
+		if strings.HasSuffix(line, c.promptHostname+"#") {
+			break
+		}
+
+		attempts -= 1
+		if attempts == 0 {
+			return nil, "", fmt.Errorf("could not find prompt, last result %q", line)
+		}
+	}
+
+	// Send comand.
+	c.writeLine(ctx, command)
+
+	// First, read until prompt again.
+	if _, err := c.readUntil(ctx, c.promptHostname+"#"); err != nil {
+		return nil, "", fmt.Errorf("could not get command hostname echo: %v", err)
+	}
+
+	loopback, err := c.readUntil(ctx, "\r\n")
+	if err != nil {
+		return nil, "", fmt.Errorf("could not get command loopback: %v", err)
+	}
+	loopback = strings.Trim(loopback, "\r\n")
+	c.trace(ctx, "effective command: %q", loopback)
+
+	// Read until we have a standalone prompt with no newline afterwards.
+	data, err := c.readUntil(ctx, c.promptHostname+"#")
+	if err != nil {
+		return nil, "", fmt.Errorf("could not get command results: %v", err)
+	}
+
+	lines := []string{}
+	for _, line := range strings.Split(data, "\r\n") {
+		if line == c.promptHostname+"#" {
+			break
+		}
+		lines = append(lines, line)
+	}
+	c.trace(ctx, "command %q returned lines: %v", command, lines)
+
+	return lines, loopback, nil
+}