Novell LINUX ENTERPRISE DESKTOP 11, Руководство пользователя

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14.2 The ssh Program
Using the ssh program, it is possible to log in to remote systems and work interactively.
It replaces both telnet and rlogin. The slogin program is just a symbolic link pointing
to ssh. For example, log in to the host sun with the command
ssh sun
. The host then
prompts for the password on sun.
After successful authentication, you can work on the remote command line or use inter-
active applications, such as YaST. If the local username is different from the remote
username, you can log in using a different login name with
ssh -l augustine
sun
or
ssh augustine@sun
.
Furthermore, ssh offers the possibility to run commands on remote systems, as known
from rsh. In the following example, run the command
uptime
on the host sun and
create a directory with the name
tmp
. The program output is displayed on the local
terminal of the host jupiter.
ssh otherplanet "uptime; mkdir tmp"
Password:
1:21pm
up 2:17, 9 users, load average: 0.15, 0.04, 0.02
Quotation marks are necessary here to send both instructions with one command. It is
only by doing this that the second command is executed on sun.
14.3 scp—Secure Copy
scp copies files to a remote machine. It is a secure and encrypted substitute for rcp. For
example,
scp MyLetter.tex sun:
copies the file
MyLetter.tex
from the host
jupiter to the host sun. If the username on jupiter is different than the username on sun,
specify the latter using the
username@host
format. The
-l
option has a different
meaning for this command.
After the correct password is entered, scp starts the data transfer and shows a growing
row of asterisks to simulate a progress bar. In addition, the program displays the esti-
mated time of arrival to the right of the progress bar. Suppress all output by giving the
option
-q
.
162 Security Guide