Yet another technical post about DELL PowerSwitch S4048-ON that I am configuring.
Secure shell (SSH) is a protocol for secure remote login and other secure network services over an insecure network. Dell Networking OS is compatible with SSH versions 1.5 and 2, in both the client and server modes. SSH sessions are encrypted and use authentication.
The RSA-SSH authentication permits the user to establish an SSH session without entering a password. This allows the user to use a custom script, for example, to automatically launch an SSH session to a Force10 switch, eliminating the potential security vulnerability of including a password in the script.
If you just unpack you will get an empty switch that does not listen any network connection. Firstly you should get a console cable. My switch has a micro USB interface on front-panel for console connection. So I’m plug-in a usual USB cable into this port, then install a drivers for COM-ports and connect to the switch with this settings:
115200-baud rate No parity 8 data bits 1 stop bits No flow control
If you have seen an input invitation like this:
You can start to configure a network interfaces and SSH server.
CONF mode with
Create a user with name
admin and privilege level
<password> enter the strong password here).
Dell(config)# username admin password <password> privilege 15
The privilege level need to restrict access to commands.
This level should between from 0 to 15. The default privilege level is 1.
The user with privilege level 15 is like
root without any restrictions.
It allows to access to the system begins at EXEC
Privilege mode, and all commands are available.
Configure Management interface
A Management interface need to remote configure and run commands on the switch. It use static or dynamic IP address.
Let’s add an IP
10.0.0.1/24 to the first management interface. Then enable it and exit.
Dell(config)# interface managementethernet 1/1 Dell(conf-if-ma-0/0)# ip add 10.0.0.1/24 Dell(conf-if-ma-0/0)# no shutdown Dell(conf-if-ma-0/0)# exit
Configure SSH server
Just input this command
Dell(config)# ip ssh server enable Dell(config)# ip ssh server version 2
Generate keys for the SSH server
Dell(config)# crypto key generate rsa
Enable password auth
Enable a password authentication
Dell(config)# ip ssh password-authentication enable
Enable SSH-RSA password auth
Enable a RSA authentication
Dell(config)# ip ssh rsa-authentication enable
Copy your public part of RSA-key (
.ssh/id_rsa.pub) into internal
flash:// memory from remote host (
Dell# copy scp://username:email@example.com/.ssh/id_rsa.pub flash://id_rsa.pub
Add authentication with this key
Dell# ip ssh rsa-authentication my-authorized-keys flash://id_rsa.pub Creating ADMIN_DIR/ssh RSA keys added to user's list of authorized-keys. Delete the file flash://id_rsa.pub : (yes/no) ? yes
Try to connect
So we configure an management IP of switch -
You can now SSH to the switch using RSA authentication.
The user will encrypt the initial connection using the private key, which the switch will authenticate using the public key; no password exchange is necessary.
$ ssh firstname.lastname@example.org
If it will successfully you see the hostname of device -
Display SSH connection information
In the end of configuring I want to show a status of SSH with command
show ip ssh
Dell# show ip ssh SSH server : enabled. SSH server version : v2. SSH server vrf : default. SSH server ciphers : aes256-ctr,aes256-cbc,aes192-ctr,aes192-cbc,aes128-ctr,aes128-cbc,3des-cbc. SSH server macs : hmac-sha2-256,hmac-sha1,hmac-sha1-96,hmac-md5,hmac-md5-96. SSH server kex algorithms : diffie-hellman-group-exchange-sha1,diffie-hellman-group1-sha1,diffie-hellman-group14-sha1. Password Authentication : enabled. Hostbased Authentication : disabled. RSA Authentication : enabled. Challenge Response Auth : disabled. Vty Encryption HMAC Remote IP * 0 aes128-ctr hmac-sha2-256 10.0.0.2
In this article I want to show how to enable SSH-server on Dell Networking system.
Also this setup make possible to secure communicate with the device without any passwords.
It uses RSA-SSH authentication and connection with imported public (
- SSH Key Auth on Dell PowerConnect Switches - another blog post with the similar problem
- Dell Command Line Reference Guide for the S4048–ON System - dell man page included full command list