SSH is a wonderful tool. It allows you to run commands on a remote host, either manually, or from scripts. Obviously, since it’s a remote connection, you must authenticate yourself to the remote host. There are several ways of doing this.
When using SSH in a script, most pages tell you to use public keys. While this is an excellent idea, it’s sometimes just not possible due to policy. This Expect script fakes a regular username-password login
#!/usr/bin/expect -f
set target [lindex $argv 0]
set password [lindex $argv 1]
set command [lindex $argv 2]spawn ssh $target $command
match_max 100000
# Look for passwod prompt
expect “*?assword:*”
# Send password aka $password
send — “$password\r”
# send blank line (\r) to make sure we get back to gui
send — “\r”
expect eof
This script can be run like this:
./ssh-passwd.ex root@192.0.2.1 password “ls /root”
