Red Hat ENTERPRISE LINUX 5 - VIRTUAL SERVER ADMINISTRATION, Руководство по развертыванию

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Chapter 18. OpenSSH
236
18.7.3.3. Generating an RSA Key Pair for Version 1.3 and 1.5
Use the following steps to generate an RSA key pair, which is used by version 1 of the SSH Protocol.
If you are only connecting between systems that use DSA, you do not need an RSA version 1.3 or
RSA version 1.5 key pair.
1. To generate an RSA (for version 1.3 and 1.5 protocol) key pair, type the following command at a
shell prompt:
ssh-keygen -t rsa1
Accept the default file location (
~/.ssh/identity
). Enter a passphrase different from your
account password. Confirm the passphrase by entering it again.
The public key is written to
~/.ssh/identity.pub
. The private key is written to
~/.ssh/
identity
. Do not give anyone the private key.
2. Change the permissions of your
.ssh
directory and your key with the commands
chmod 755
~/.ssh
and
chmod 644 ~/.ssh/identity.pub
.
3. Copy the contents of
~/.ssh/identity.pub
into the file
~/.ssh/authorized_keys
on the
machine to which you wish to connect. If the file
~/.ssh/authorized_keys
does not exist, you
can copy the file
~/.ssh/identity.pub
to the file
~/.ssh/authorized_keys
on the remote
machine.
4. If you are running GNOME, skip to
Section 18.7.3.4, “Configuring
ssh-agent
with a GUI”
. If you
are not running GNOME, skip to
Section 18.7.3.5, “Configuring
ssh-agent
”
.
18.7.3.4. Configuring
ssh-agent
with a GUI
The
ssh-agent
utility can be used to save your passphrase so that you do not have to enter it each
time you initiate an
ssh
or
scp
connection. If you are using GNOME, the
gnome-ssh-askpass
package contains the application used to prompt you for your passphrase when you log in to GNOME
and save it until you log out of GNOME. You will not have to enter your password or passphrase for
any
ssh
or
scp
connection made during that GNOME session. If you are not using GNOME, refer to
Section 18.7.3.5, “Configuring
ssh-agent
”
.
To save your passphrase during your GNOME session, follow the following steps:
1. You will need to have the package
gnome-ssh-askpass
installed; you can use the command
rpm -q openssh-askpass
to determine if it is installed or not. If it is not installed, install it from
your Red Hat Enterprise Linux CD-ROM set, from a Red Hat FTP mirror site, or using Red Hat
Network.
2. Select
Main Menu Button
(on the Panel) >
Preferences
>
More Preferences
>
Sessions
, and
click on the
Startup Programs
tab. Click
Add
and enter
/usr/bin/ssh-add
in the
Startup
Command
text area. Set it a priority to a number higher than any existing commands to ensure
that it is executed last. A good priority number for
ssh-add
is 70 or higher. The higher the priority
number, the lower the priority. If you have other programs listed, this one should have the lowest
priority. Click
Close
to exit the program.
3. Log out and then log back into GNOME; in other words, restart X. After GNOME is started, a
dialog box will appear prompting you for your passphrase(s). Enter the passphrase requested. If