Allied Telesis AT-S62 - Manual (Page 547)

AT-S62 User’s Guide
Section VII: Management Security 547
Guidelines Below are the guidelines to observe when configuring SSH:
❑ SSH requires two encryption key pairs. One key pair will function
as the host key and the other the server key. For instructions on
creating keys, refer to Creating an Encryption Key on page 500.
❑ The two encryption key pairs must be of different lengths of at
least one increment (256 bits) apart. The recommended bit size
for a server key is 768 bits. The recommended size for the host key
is 1024 bits.
❑ You activate and configure SSH on the master switch of an
enhanced stack, not on slave switches.
❑ The AT-S62 software uses well-known port 22 as the SSH default
port.
General Steps to
Configuring
SSH
Configuring the SSH server involves several procedures. This section lists
the procedures you need to complete to configure the SSH feature.
1. Create two encryption key pairs on the master switch of the
enhanced switch. One pair will function as the host key and the other
the server key.
2. Configure and activate the Secure Shell server on the switch by
specifying the two encryption keys in the server software.
For instructions, see Configuring the SSH Server on page 548.
3. Install SSH client software on your management workstation.
Follow the directions provided with the client software. You can
download SSH client software from the Internet. Two popular SSH
clients are PuTTY and CYGWIN.
4. Disable the Telnet server.
Although the switch allows the SSH and Telnet servers to be
enabled simultaneously, allowing Telnet to be enabled negates
the security of the SSH feature. To disable the Telnet server, see
Enabling or Disabling the Telnet Server on page 73.
5. Logon to the switch from your SSH management workstation.