在Linux操作系统下实现自动Telnet主要有三种方式： Shell实现、Expect实现和Python实现。今天给大家详细介绍这三种方法的实现步骤。
一、Shell实现，文件名：autotelnet.sh，代码如下：
(sleep 1;echo "root";sleep 1;echo "123456";sleep 1;echo "en";sleep 1;echo "1qazse4";sleep 1;echo "conf t";sleep 1;echo "int fa0/1";sleep 1;echo "switchport mode multi";sleep 1;echo "end";sleep 1;echo "exit") | telnet 10.32.17.10
二、Expect来实现，文件名：autotelnet.exp，代码如下：
#!/usr/bin/expect
set timeout 100
set TERM xterm
set SERVER "10.32.17.10"
set USER "root"
set PASSWD "123456"
spawn telnet
expect "telnet> "
send "open $SERVERr"
expect "Username:"
send "$USERr"
expect "Password:"
send "$PASSWDr"
expect "longjiang-zero>"
send "enr"
expect "Password:"
send "$PASSWDr"
expect "longjiang-zero#"
send "conf tr"
expect "longjiang-zero(config)#"
send "int fa0/1r"
expect "longjiang-zero(config-if)#"
send "switchport mode multir"
expect "longjiang-zero(config-if)#"
send "endr"
expect "longjiang-zero#"
send "exitr"
interact
三、 Python来实现，文件名：autotelnet.py，代码如下：
#!/usr/bin/python
import telnetlib
host = '10.32.17.10'
user = 'root'
password = '123456'
commands = ['en',password,'conf t','int fa0/1','switchport mode multi','end']
tn = telnetlib.Telnet(host)
tn.read_until("Username:")
tn.write(user + "n")
tn.read_until("Password:")
tn.write(password + "n")
for command in commands:
tn.write(command+'n')
tn.write("exitn")
print tn.read_all()
print 'Finish!'
