UNIX for Dummies Questions & Answers

Hi Newbie here
I am having problems with automating sFTP transfers.

Just to save time - SCP is not an option as sFTP is stipulated by controllers of far end server.

Ineed to automate sFTP transfer of a single file, once a day to a remote server to which i have no control over.
I am using: Solaris server (Solaris 9 9/05 s9s_u8wos_05 SPARC), the UNIX provided OpenSSH, SHELL=/bin/sh

So far i have mangaged to set up the required DSA keys and connected to the server manually using sFTP without having to enter a password(so i know the keys are working ok) and manually put a test file on there.

My next task and the bit i am stuck on is to write a script to automate the daily file upload - same filename every day and simple overwrite.

Problem is that all posts i have currently seen suggest to use -b option and write sFTP in separate file, sFTP reports that -b is an illegal option so need to write a script that will initiate the connection, pass the sFTP commands required and then close the connection so that i can put it in the crontab for running once a day.

Any help would be appreciated
Thanks

Code:

#!/bin/ksh
cd /path/to/local/file
/usr/bin/sftp 11.22.1.2 <<EOF
put localfilename remotefilename
exit

This is a here document. Is this what you are asking? Or is it something to do with cron? 11.22.1.2 is the remote host name or ip address. cron has to run under the crontab for the user with the keys.

Hi
Thanks for the reply.
It's not a cron problem - i haven't got as far as putting in the cron yet.

I can manually connect:
sftp username@host

this automatically connects me as i have already set up the keys.

I can then transfer file: put file
Then disconnect: exit

That is all that is required except for the fact i want to do is automatically via a script so it can go in the cron - just dont know how to get the sftp commands to be read and get the connection to exit without doing it manually
Cheers

I don't believe you can run sftp in a script. I had to use expect to "automate" it. There are several postings on expect and its use. Good luck.

Here is some code that I put together from posts that I found here. Hope it helps.

Code:

#!../expect -f
# To make sftp non-interactive
# login is the first arg. password is the second arg
set force_conservative 1
if {$force_conservative} {
    set send_slow {1 .1}
    proc send {ignore arg} {
         sleep .1
         exp_send -s -- $arg
    }
}
set timeout -1
set password [lindex $argv 1]
set login [lindex $argv 0]
spawn sftp [lindex $argv 0]
match_max 1000000
expect "$login's password:"
send -- "$password\r"
expect "sftp>"
send -- "put -P /lsf1/hurdata/HMC*\r"
expect "sftp>"
send -- "ls -l\r"
expect "sftp>"
send -- "quit\r"
expect eof

It's been done. It's designed to. The trick to scripting a login is to use a non-interactive login method, like keys. The script you've quoted has a security hole big enough to drop a cow through. Passing a password through commandline parameters lets anyone logged into the system see it, in plaintext!

This is why things like scp, sftp, ssh, sudo, and su won't accept passwords through anything but a terminal. It's a subtle hint, written in mile-high flashing neon letters: This is a bad idea. You're not supposed to do this. By using expect to brute-force it into running the wrong way, you've learned the wrong lesson.

Doubly so, since the OP has already said they already have working passwordless logins, arranged the proper way: keys. Logging in is not the problem here. Please think next time before you suggest brute-forcing passwords insecurely.

---------- Post updated at 01:34 PM ---------- Previous update was at 01:28 PM ----------

This works fine for me when passwordless login's arranged:

Code:

cat <<EOF | sftp user@host
ls
EOF

It logs in, does ls, and quits. You can have as many lines of commands as you want, just add them:

Code:

cat <<EOF | sftp user@host
cd public_html
put file_a
put file_b
put file_c
EOF

let try like this

Code:

# crontab -e
00 14 * * * /root/.myscripts/sftpdoit.sh transferfile.xml

Code:

# cat /root/.myscripts/sftpdoit.sh
#!/bin/bash
myfile="$1"
/usr/bin/sftp youruser@yourhost <<EOF
put $myfile
quit
EOF

Thanks very much for the help i have now successfully tested a script:

Code:

sftp user@host.com <<EOF
lcd LOCALFOLDER
put FILE.TXT
quit
EOF

This done the job for
Thanks again