Accessing the Device

Many places, you need a backstage pass to see what is going on behind the curtain, and different levels can get you access to the dressing rooms or tour bus. The following sections explore the kind of “backstage”passes Junos OS devices offer and how close you can get to what goes on behind the curtain.

Accessing your device with Telnet

The basic way of accessing a remote device is using Telnet. After you configure an IP address on the management interface (whether that interface is out-of-band or in-band), you can access the device by opening up a Telnet session to that address. For example, if you configure your device with a management interface address of, you should be able to access the device with the Telnet session:

telnet: connect to address Connection refused
telnet: Unable to connect to remote host

Oops, something went wrong. Access to the device must be explicitly configured on the device (which is part of the initial setup in Chapter 6, but many people don't complete it!). More specifically, particular modes of access must be explicitly enabled. In this case, you're trying to access the device using Telnet, so you must tell the device to allow Telnet connections. To configure the Telnet service on the device, do the following:

system {
    services {

After Telnet services are enabled on the device, the Telnet request is successful:

> telnet ...

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