# Telnet and rsh

Telnet and rsh are applications you use to access the command-line interface (CLI) of the storage system.

### Using Telnet to access the storage system:

To access the storage system, complete the following steps:

1. Log in with your user name and password.

2. Issue commands exactly as you do at the storage system console.

Following is an example:

> `vero% telnet jeckle
> Trying 172.24.1.20...
> Connected to jeckle.lab.netapp.com.
> Escape character is '^]'.`

> `login: root
> Password:
> jeckle> Fri Feb 7 01:54:02 GMT [jeckle: telnet_0:info]: root logged in from host: vero.eng.netapp.com`

> `jeckle> version
> NetApp Release 6.4X10: Thu Jan 23 03:37:23 PST 2003
> <1d>
> jeckle> snap list
> Volume vol0
> working...`

> `%/used %/total date name
> ---------- ---------- ------------ --------
> 0% ( 0%) 0% ( 0%) Feb 07 00:00 nightly.0
> 0% ( 0%) 0% ( 0%) Feb 06 20:00 hourly.0
> 0% ( 0%) 0% ( 0%) Feb 06 16:00 hourly.1`

> `Volume vol1
> working...`

> `%/used %/total date name
> ---------- ---------- ------------ --------
> 11% (11%) 0% ( 0%) Feb 07 00:00 nightly.0
> 23% (14%) 0% ( 0%) Feb 06 20:00 hourly.0
> 32% (14%) 0% ( 0%) Feb 06 16:00 hourly.1
> jeckle>`

### Using rsh to access the storage system:

To access the storage system, complete the following step:

Pass a string that is to be executed as a single command in the storage system console, for example, `rsh heckle snap list.`

After returning the output to the console, rsh exits.

The following is an example:

> `vero% rsh heckle snap list
> Volume nate_kitten1_1040097652
> working...`

> `%/used %/total date name
> ---------- ---------- ------------ --------
> 19% (19%) 0% ( 0%) Feb 07 00:00 nightly.0
> 35% (24%) 0% ( 0%) Feb 06 20:00 hourly.0
> 46% (23%) 0% ( 0%) Feb 06 16:00 hourly.1`

> `Volume vol0
> working...`

> `%/used %/total date name
> ---------- ---------- ------------ --------
> 0% ( 0%) 0% ( 0%) Feb 07 00:00 nightly.0
> 0% ( 0%) 0% ( 0%) Feb 06 20:00 hourly.0
> 0% ( 0%) 0% ( 0%) Feb 06 16:00 hourly.1
> vero %`

With rsh, access is determined by the file /etc/hosts.equiv.

| See the storage system man pages of hosts.equiv and rshd on the NetApp on the Web (NOW) to learn more about the /etc/hosts.equiv file.

Enter the host names and the user names (optional) in the file as shown below:

> `vero joe``
> vero root``
> mayo`

The users joe and root can use rsh to access the storage system from the host vero. However, any user can use rsh from the host mayo.

Executing a simple command rsh storage_system_name does not log you in to the shell, unlike on a UNIX system, because there is no shell to run (the console is an integral part of the Data ONTAP operating system). You can execute multiple commands by separating them with a semicolon, as shown in the following example:

> priv set -q advanced; help

The preceding example prints the available advanced level commands. Like a UNIX shell this time, the storage system executes these rsh commands in a separate context. The preceding command does not affect the priv level of the current console session.

### Advantages of using Telnet and rsh:

Following are the advantages of using Telnet and rsh:

- The storage system CLI is often the first available interface to the new functionality.

- It is useful for system administrators who are performing ad-hoc administrative tasks.

### Disadvantages:

Although there are advantages to using Telnet and rsh, NetApp recommends that you do not use Telnet or rsh while writing management code because of the following issues:

- Parsing the command line output is difficult. There are cases, such as in some reports, in which a field is occasionally empty. Furthermore, CLI changes can sometimes break code that previously worked (however, NetApp makes a continual effort to minimize backward-incompatible CLI changes).

- Using rsh from Windows code is difficult because Windows pops up a separate command-line window (over which you do not have control) while rsh is running. If you issue a command that takes time to execute, you're stuck with a window in front of your application until the command returns. If there is a network partition, or if the storage system is down, the pop-up window remains until the TCP timeout expires.

Related Topics

- System Administration Storage Management Guide for Data ONTAP 6.4

- Accessing a storage system with a Remote Shell connection

- Accessing a storage system from the console or a Telnet session