Linux/Unix shell内嵌expect自动配置多台主机SSH互信

在自动化测试，或者Oracle RAC安装过程中，需要配置主机之间SSH 无密码访问，当有多台主机时，配置起来很麻烦，网上的很多类似脚本拿到本机有问题，所以自己写了一个：
   

#!/bin/bash

NUM_OF_NODES=
NODE1=""
NODE2=""
NODE3=""
NODE4=""
NODE5=""

USER=root
EXPECT=/usr/bin/expect
PASSWD=""
#USER_PROMPT="*$ "
USER_PROMPT="*# "

if [ "x${NODE1}" == "x" -o "x${USER}" == "x" -o "x${PASSWD}" == "x" ]; then
    echo ""
    echo "Please set the NODE INFO, USER and PASSWD"
    echo "then $0 to start..."
    exit 1
fi

declare -i l_i=1
while [ $l_i -le $NUM_OF_NODES ]
do
    eval l_current_node=\$NODE$l_i

    $EXPECT <<EOF
    spawn ssh $USER@$l_current_node
    expect "*(yes/no)?*" {
        send -- "yes\r"
        expect "*?assword:*"
        send -- "$PASSWD\r"
    } "*?assword:*" {send -- "$PASSWD\r"}
    expect "$USER_PROMPT"
    send -- "ssh-keygen -t rsa -q -f ~/.ssh/id_rsa -P '' \r"
    expect "*Overwrite (yes/no)? " {
        send -- "yes\r"
    } "$USER_PROMPT" {send -- "\r"}
    expect "$USER_PROMPT"
    send -- "cat ~/.ssh/id_rsa.pub | ssh $USER@$NODE1 'cat - >> ~/.ssh/authorized_keys' \r"
    expect "*(yes/no)?*" {
        send -- "yes\r"
        expect "*?assword:*"
        send -- "$PASSWD\r"
    } "*?assword:*" {send -- "$PASSWD\r"}
    expect "$USER_PROMPT"
    send -- "exit\r"
EOF
    ((l_i++))
done

declare -i l_n=1
while [ $l_n -le $NUM_OF_NODES ]
do
    eval l_current_node=\$NODE$l_n
    $EXPECT <<EOF

    spawn ssh $USER@$NODE1
    expect "*?assword:*" {
        send -- "$PASSWD\r"
        expect "$USER_PROMPT"
    } "$USER_PROMPT" {send -- "scp ~/.ssh/authorized_keys $l_current_node:~/.ssh/ \r"}
    expect "*?assword:*"
    send -- "$PASSWD\r"
    expect "$USER_PROMPT"
    send -- "exit\r"
EOF
    ((l_n++))
done