Generating Ssh Keys; Setting Ssh Key Pair - Cisco ASR 5500 Administration Manual

Getting Started
• chacha20-poly1305@openssh.com – ChaCha20 symmetric cipher, Poly1305 cryptographic Message
Authentication Code [MAC], OpenSSH
The default string for algorithm is:
blowfish-cbc,3des-cbc,aes128-cbc,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com,
chacha20-poly1305@openssh.com
Step 3 Exit the SSH Configuration mode.
host_name
[local]
host_name
[local]

Generating SSH Keys

The ssh generate command generates a public/private key pair which is to be used by the SSH server. The
v1-rsa keyword has been removed from and the v2-dsa keyword concealed within the ssh generate CLI
command. The only keyword available for generating SSH keys is v2-rsa.
Important
Step 1 Enter the context configuration mode:
host_name
[local]
host_name
[local]
Step 2 Generate an SSH key pair.
host_name
[local]
host_name
[local]

Setting SSH Key Pair

The ssh key command sets the public/private key pair to be used by the system. The v2-dsa keyword is
concealed in the ssh key command.
Specify the SSH key pair parameters.
[local]host_name(config-ctx)#
Notes:
• data is the encrypted key expressed as an alphanumeric string of 1 through 1023 characters
• length octets is the length of the encrypted key in octets expressed as an integer from 0 through 65535
end
(config-sshd)#
#
The generated key pair remains in use until the command is issued again.
context context_name
(config)#
(config-ctx)#
ssh generate key type v2-rsa
(config-ctx)#
(config-ctx)#
ssh key data length octets type v2-rsa
ASR 5500 System Administration Guide, StarOS Release 19
SSH Keys
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