"Linux" SSH Remote execution Command __linux

Sometimes, the command to execute a remote machine locally using SSH can easily handle some repetitive work. We want to do this:

No manual input password

Supports execution of multiple commands, executing shell scripts

Support to execute sudo command

No manual input password

We can use SSH mutual trust, sshpass and expect tools to avoid manual transmission of passwords. The use process may encounter the following tedious scenario where you need to enter Yes manually:

$ ssh Username@hostname

The authenticity of host ... can ' t be established.

ECDSA Key fingerprint is ...

Are you sure your want to continue connecting (yes/no)?

To avoid this scenario, add the following parameters to the SSH command:

$ ssh-o "Stricthostkeychecking No" username@password

SSH Mutual trust

SSH Trust configuration is very simple, first generated SSH key:

$ ssh-keygen

Copy public key to the trusted party:

$ ssh-copy-id-i ~/.ssh/id_rsa.pub Username@hostname

After the execution of the command:

$ ssh-o "stricthostkeychecking no" username@password cmd

Sshpass

Sshpass is a non-interactive SSH password verification tool that is installed before use:

$ yum Install Sshpass

For example:

$ sshpass-p Password Ssh-o "stricthostkeychecking no" username@hostname cmd

Expect

Expect is a software tool for automating control and testing. Although the study cost is high, but the expect function is formidable, uses the expect to be possible to execute the remote command conveniently. Install before use:

$ yum Install expect

For example:

#!/usr/bin/expect

Spawn Ssh-o "Stricthostkeychecking No" username@hostname

Expect "*assword*"

Send "Password"

Expect "*$*"

Send "command"

Expect "*$*"

Send "Exit"

Expect EOF

Expect not only supports SSH, but also supports SCP, FTP and other tools.

Support for multiple commands and scripts

Execute more than one command

Sshpass and expect are very similar in support of multiple commands, just use the && connection command:

# SSH Trust

$ ssh-o "stricthostkeychecking no" Username@password "cmd1 && cmd2"

For example:

# Sshpass

$ sshpass-p Password Ssh-o "stricthostkeychecking no" Username@password "ls-a && mkdir test"

# expect

......

Expect "*$*"

Send "ls-a && mkdir test"

......

Execute local Script

For executing local scripts, SSH and Sshpass are similar in usage.

# SSH Trust

$ ssh-o "stricthostkeychecking No" Username@password bash-s < shell_script.sh

# Sshpass

$ sshpass-p Password Ssh-o "stricthostkeychecking no" Username@password bash-s < shell_script.sh

For expect, you first need to copy the script to the remote host, and then execute the script on the remote host, as follows:

...

# Copy script to remote host

Spawn Scp-o "Stricthostkeychecking no" shell_script.sh username@hostname:~/

Expect "*assword*"

Send "Password"

Expect "*100%*"

Expect EOF

# Execute The shell script at remote host

Spawn Ssh-o "Stricthostkeychecking No" username@hostname

Expect "*assword*"

Send "Password"

Expect "*$*"

Send "sh shell_script.sh"

......

Support for sudo command execution

Some commands require sudo permission to execute, but we do not want to enter the password repeatedly, we can change each command as follows: