Realizing the mutual trust of two machines based on OpenSSH

1. Server-side configuration files :#vim/etc/ssh/sshd_config

Protocol 2 (protocol version V2)

AddressFamily any (service on which type of address, any means support IPv4,IPv6)

ListenAddress 0.0.0.0 (address of service provided, default is all addresses configured on the host)

Keyregenerationinterval 1h(Regenerate key time, default 1 hours)

Serverkeybits 1024x768 (default length of secret key)

Syslogfacility Authpriv (defines the range of log messages)

LogLevel INFO (log level)

Logingracetime 2m (login tolerance period, default is two minutes)

Permitrootlogin Yes (allows administrators to log in directly)

Maxauthtries 6 (maximum number of logon attempts allowed)

Pubkeyauthentication Yes (key-based authentication is allowed)

passwordauthentication Yes (password-based authentication is allowed)

Banner None(whether to display the welcome banner when the user logs in)

2.ssh Client Usage :

a) ssh-l user name remote host name [ command ]

b) ssh user name @ remote Host name

-X can execute graphical commands on the remote host

3. How to implement key-based authentication:

A host is a client (implemented based on a user)

1) generate a pair of secret keys

Ssh-keygen

-t {RSA|DSA} specifies the algorithm

-f/path/to/keyfile specifying a key file

-N ' password ' to specify password

2) transfer the public key to a . Ssh/authorized_keys file in a user's home directory on the server side

Using the File Transfer tool (SSH-COPY-ID,SCP)

Ssh-copy-id-i/path/to/ generated public key user name @ host

3) Test Login

4.SCP: ssh -based remote replication command, can be implemented between the host encrypted transmission data

Usage:SCP [ options ] Source Purpose

-R recursive replication, used when copying directories

-a reserved permission, recursive replication, used when copying directories

5. Experiment: Two-machine mutual trust

1) Premise: two hosts fsy1(192.168.113.128) and fsy2( 192.168.113.129) network connectivity

2) Procedure:

Client:

#ssh-keygen-t RSA (Generate secret key)

Direct carriage return when input is required

#ssh-copy-id-i/root/.ssh/id_rsa.pub [email protected] (copy your own public key to the peer host)

Server:

#ssh-keygen-t RSA

#ssh-copy-id-i/root/.ssh/id_rsa.pub [email protected]

Finally, the test can be done.

Realizing the mutual trust of two machines based on OpenSSH