Linux virtual machines automatically configure SSH password-free login in batches

1. The environment required by the script

Need to pay attention: each machine needs to install expect.
If you connect to the external network, you can use yum to install.
yum install expect.
If there is no condition to connect to the external network, you can also use the rpm package to install

2. Scripting

The script is written as follows: the
first parameter is the name of the user who wants to set ssh, here is spark, the
second parameter is the password corresponding to the user, and the
third parameter is the ip list of the machine to set up interworking ssh
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vi autoSSH.sh

#!/bin/sh
DEST_USER=$1
PASSWORD=$2
HOSTS_FILE=$3
if [ $# -ne 3 ]; then
    echo "Usage:"
    echo "$0 remoteUser remotePassword hostsFile"
    exit 1
fi

SSH_DIR=~/.ssh
SCRIPT_PREFIX=./tmp
echo ===========================
 # 1. prepare  directory .ssh
mkdir $SSH_DIR
chmod 700 $SSH_DIR

# 2. generat ssh key
TMP_SCRIPT=$SCRIPT_PREFIX.sh
echo  "#!/usr/bin/expect">$TMP_SCRIPT
echo  "spawn ssh-keygen -b 1024 -t rsa">>$TMP_SCRIPT
echo  "expect *key*">>$TMP_SCRIPT
echo  "send \r">>$TMP_SCRIPT
if [ -f $SSH_DIR/id_rsa ]; then
    echo  "expect *verwrite*">>$TMP_SCRIPT
    echo  "send y\r">>$TMP_SCRIPT
fi
echo  "expect *passphrase*">>$TMP_SCRIPT
echo  "send \r">>$TMP_SCRIPT
echo  "expect *again:">>$TMP_SCRIPT
echo  "send \r">>$TMP_SCRIPT
echo  "interact">>$TMP_SCRIPT

chmod +x $TMP_SCRIPT

/usr/bin/expect $TMP_SCRIPT
rm $TMP_SCRIPT

# 3. generat file authorized_keys
cat $SSH_DIR/id_rsa.pub>>$SSH_DIR/authorized_keys

# 4. chmod 600 for file authorized_keys
chmod 600 $SSH_DIR/authorized_keys
echo ===========================
# 5. copy all files to other hosts
for ip in $(cat $HOSTS_FILE)  
do
    if [ "x$ip" != "x" ]; then
        echo -------------------------
        TMP_SCRIPT=${SCRIPT_PREFIX}.$ip.sh
        # check known_hosts
        val=`ssh-keygen -F $ip`
        if [ "x$val" == "x" ]; then
            echo "$ip not in $SSH_DIR/known_hosts, need to add"
            val=`ssh-keyscan $ip 2>/dev/null`
            if [ "x$val" == "x" ]; then
                echo "ssh-keyscan $ip failed!"
            else
                echo $val>>$SSH_DIR/known_hosts
            fi
        fi
        echo "copy $SSH_DIR to $ip"
                
        echo  "#!/usr/bin/expect">$TMP_SCRIPT
        echo  "spawn scp -r  $SSH_DIR $DEST_USER@$ip:~/">>$TMP_SCRIPT
        echo  "expect *assword*">>$TMP_SCRIPT
        echo  "send $PASSWORD\r">>$TMP_SCRIPT
        echo  "interact">>$TMP_SCRIPT
        
        chmod +x $TMP_SCRIPT
        #echo "/usr/bin/expect $TMP_SCRIPT" >$TMP_SCRIPT.do
        #sh $TMP_SCRIPT.do&
    
        /usr/bin/expect $TMP_SCRIPT
        rm $TMP_SCRIPT
        echo "copy done."                
    fi
done

echo done.

3. Script running mode

Run the script ./autoSSH.sh spark 123456 /etc/hosts.conf
can be free ssh secret landing between several machines after the completion of the execution