Location>code7788 >text

Shell scripts to implement multiple servers with password-free

Popularity：846 ℃/2025-03-19 10:04:06

Introduction

This script (auto_ssh_batch.sh) is used to quickly configure SSH password-free login between multiple hosts, and supports remote transfer of scripts/files and execution of commands. passpassThe document provides unified authentication credentials, passednodesThe file defines the target host list to achieve batch automation.

download

git clone /wesley_li0/

Special Note (Company):

Using non-root users requires creating a user and adding a root group, and configuring trusted sudo permissions. You can use commands to implement it

USER: Username

PASSWORD: Password

USER=your_user && PASSWORD=your_password && useradd -m -G root -s /bin/bash "$USER" && echo "$USER:$PASSWORD" | chpasswd && echo "$USER ALL=(ALL) NOPASSWD:ALL" >> /etc//$USER

Prerequisites

  1. operating system: The target host must be a RHEL/CentOS 7 system (due to dependencysshpass-1.06-2.el7.x86_64.rpm）。
  2. Permission Requirements：
    • The host that executes the script must have root permissions to installsshpass。
    • The SSH service for all target hosts is started and the firewall allows SSH ports (default 22) to communicate.
    • All host usernames and passwords are the same (the password needs to be changed after the password is completed and it will not affect the password exemption)

Document preparation: Ensure the following files and directory structures exist:

/root/NoPassword/ # Script storage and user's home directory
 ├── auto_ssh_batch.sh # main execution script
 ├── bin
 │ └── generate_ssh_key.sh # Remote execution script to be distributed
 ├── config
 │ └── nodes # Store the target host IP and node ID
 └── main
     └── sshpass-1.06-2.el7.x86_64.rpm # sshpass installation package

Configuration file format

**nodes**** document**
Each line defines the IP and node ID of the target host (the ID should be consistent with the subsequent cluster automation script ID. If there is no need to execute the cluster script, the ID is customized and used only as the output machine identifier), separated by spaces:

IP_Address Node_ID User Password

Example:

192.168.1.10 1 root root123
192.168.1.11 2 root root123

How to use scripts

SSH custom port

- SSH port specification, modify the `SSH_PORT` variable in the `auto_ssh_batch.sh` script
 - `SSH_PORT` This variable is used to specify the SSH link port, default 22

Place dependent files

- Put the `sshpass` RPM package into the `main/` directory (already existed by default).
 - Make sure that the `generate_ssh_key.sh` script is located in the `bin/` directory.

Give execution permissions and execute scripts

sudo chmod +x auto_ssh_batch.sh
 sudo sh auto_ssh_batch.sh



 # Use ssh verification after the script is run
 # Default ssh port
 ssh username@ip

 # Specify the ssh port
 ssh -p xx username@ip

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Script execution process

  1. File Check
    verifyconfig/passandconfig/nodesWhether it exists and whether the format is correct.
  2. Initialize the environment
    • Generate the local SSH key pair (if not present).
    • Installsshpass(If not installed).
  3. Batch operation
    TraversalnodesEach IP in the file:
    • Distribution of public keys:usesshpassCopy the public key to the target host to achieve password-free login.
    • Transfer files:Willgenerate_ssh_key.sh、pass、nodes、sshpassUploaded to the target host/tmp。
    • Remote execution: Run on the target hostgenerate_ssh_key.sh。

Things to note

  1. Safety warning
    • Passwords in nodes files are stored in plain text and are recommended to be used only in trusted environments.
    • Script usage-o StrictHostKeyChecking=no, automatically trust the host key, and there may be a risk of man-in-the-middle attack.
  2. Error handling
    • If the public key distribution of a host fails, the script will skip the host and continue execution.
    • When a file transfer or a remote command fails, view the error output and check network connectivity.
  3. Log output
    During execution, detailed logs will be displayed, including the successful/failed host IP and operation status.

Through the above steps, you can quickly complete multi-host SSH password-free login configuration and batch remote operation.

<Previous Next>