-c
number
Determines the total number of packages to send and ends after they have
been dispatched (by default, there is no limitation set)
-f
ood ping: sends as many data packages as possible; a popular means, re-
served for root, to test networks
-i
value
Species the interval between two data packages in seconds (default: one
second)
host [options] hostname [server]
The domain name system resolves domain names to IP addresses. With this tool,
send queries to name servers (DNS servers).
ssh [options] [user@]hostname [command]
SSH is actually an Internet protocol that enables you to work on remote hosts
across a network. SSH is also the name of a Linux program that uses this protocol
to enable operations on remote computers.
17.12.2.4 Miscellaneous
passwd [options] [username]
Users may change their own passwords at any time using this command. The
administrator root can use the command to change the password of any user on
the system.
su [options] [username]
The su command makes it possible to log in under a dierent username from a
running session. Specify a username and the corresponding password. The
password is not required from root, because root is authorized to assume the
identity of any user. When using the command without specifying a username,
you are prompted for the root password and change to the superuser (root). Use
su - to start a login shell for a dierent user.
halt [options]
To avoid loss of data, you should always use this program to shut down your
system.
reboot [options]
Does the same as halt except the system performs an immediate reboot.
clear
This command cleans up the visible area of the console. It has no options.
220 Start-Up