Virtual I/O Server command-line interface

Learn about accessing and using the Virtual I/O Server command-line interface.

The Virtual I/O Server is configured and managed through a command-line interface. All aspects of Virtual I/O Server administration can be accomplished through the command-line interface, including the following:

Device management (physical, virtual, logical volume manager (LVM))
Network configuration
Software installation and update
Security
User management
Maintenance tasks

The first time you log in to the Virtual I/O Server, use the padmin user ID, which is the prime administrator user ID. You will be prompted for a new password.

Restricted shell

After logging in, you will be placed into a restricted Korn shell. The restricted Korn shell works in the same way as a standard Korn shell, except that you cannot perform the following:

Change the current working directory
Set the value of the SHELL, ENV, or PATH variables
Specify the path name of the command that contains a forward slash (/)
Redirect output of a command by using any of the following characters: >, >|, <>, >>

As a result of these restrictions, you cannot execute commands that are not accessible to your PATH variables. In addition, these restrictions prevent you from sending command output directly to a file. Instead, command output can be piped to the tee command.

After you log in, you can type help to get information about the supported commands. For example, to get help on the errlog command, type help errlog.

Execution mode

The Virtual I/O Server command-line interface functions similarly to a standard command-line interface. Commands are issued with appropriate accompanying flags and parameters. For example, to list all adapters, type the following:

lsdev -type adapter

In addition, scripts can be run within the Virtual I/O Server command-line interface environment.

In addition to the Virtual I/O Server command-line interface commands, the following standard shell commands are provided.

Table 1. Standard shell commands and their functions
Command	Function
awk	Matches patterns and performs actions on them.
cat	Concatenates or displays files.
chmod	Changes file modes.
cp	Copies files.
date	Displays the date and time.
grep	Searches a file for a pattern.
ls	Displays the contents of a directory.
mkdir	Makes a directory.
man	Displays manual entries for the Virtual I/O Server commands.
more	Displays the contents of files one screen at a time.
rm	Removes files.
sed	Provides a stream editor.
stty	Sets, resets, and reports workstation operating parameters.
tee	Displays the output of a program and copies it to a file.
vi	Edits files with full screen display.
wc	Counts the number of lines, words, bytes, and characters in a file.
who	Identifies the users who are currently logged in.

As each command is executed, the user log and the global command log are updated.

The user log contains a list of each Virtual I/O Server command, including arguments, that a user has executed. One user log for each user in the system is created. This log is located in the home directory of the user and can be viewed by using either the cat or the vi commands.

The global command log is made up of all the Virtual I/O Server command-line interface commands executed by all users, including arguments, the date and time the command was executed, and from which user ID it was executed. The global command log is viewable only by the padmin user ID, and it can be viewed by using the lsgcl command. If the global command log exceeds 1 MB, the log is truncated to 250 KB to prevent the file system from reaching its capacity.

Remote script

Secure Shell (SSH) is shipped with the Virtual I/O Server. Hence, scripts and commands can run remotely after an exchange of SSH keys. To set up and run the commands remotely, perform the following steps:

From the command line on the remote system, type the ssh command and verify that the Virtual I/O Server has been added as a known host. If not, you must perform the following steps to exchange ssh keys.
```
# ssh padmin@<vios> ioscli ioslevel
padmin@<vios>'s password:
2.1.2.0 
```
Where <vios> is either the Virtual I/O Server host name or its TCP/IP address.
Generate the public ssh key on the remote system.
Transfer the ssh key to the Virtual I/O Server. The transfer can be done by using File Transfer Protocol (FTP).
On the Virtual I/O Server, type the following command to copy the public key to the .ssh directory:
```
 $ cat id_rsa.pub >> .ssh/authorized_keys 
```
From the command line on the remote system, type the same ssh command from step 1 to add the Virtual I/O Server as a known host. The command prompts the user for a password if it has not already been added as a known host.
From the command line on the remote system, type the same ssh command from step 1 to verify that the ssh command can run without requiring the user to enter a password.