script to run multiple commands on a remote server over ssh

 Made Chatgpt write the following script. The EOF syntax is useful. In our case, we need to put in the appropriate -pPORT also.

write a bash shell script to ssh into two servers server1 and server2 with ssh keys key1.pem and key2.pem, run sudo apt upgrade on both, and show the result on the terminal.

#!/bin/bash

# Define servers and keys

SERVER1="user1@server1"

KEY1="key1.pem"

SERVER2="user2@server2"

KEY2="key2.pem"

# Function to upgrade a server

upgrade_server() {

  local SERVER=$1

  local KEY=$2

  echo "Upgrading packages on $SERVER..."

  

  ssh -i "$KEY" -o StrictHostKeyChecking=no "$SERVER" << 'EOF'

    echo "Running apt update..."

    sudo apt update

    echo "Running apt upgrade..."

    sudo DEBIAN_FRONTEND=noninteractive apt upgrade -y

EOF

}

# Upgrade both servers

upgrade_server "$SERVER1" "$KEY1"

echo "---------------------------------------------"

upgrade_server "$SERVER2" "$KEY2"