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Top Forums Shell Programming and Scripting While loop is causing ssh command to exit from script after first iteration. Post 302949536 by Aia on Monday 13th of July 2015 01:41:49 AM
Old 07-13-2015
From man ssh
Quote:
-n Redirects stdin from /dev/null (actually, prevents reading from stdin).
Code:
while read server; do
        ssh -n $server uptime
done <serverList

That would work as long as ssh is not expecting a password or paraphrase.

Since you are using bash, you can as well change the file descriptor that the read will read from.
Code:
while read -u12 server; do
        ssh $server uptime
done 12<serverList


Last edited by rbatte1; 07-13-2015 at 09:48 AM.. Reason: Quote tags
 

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SSH-ARGV0(1)						    BSD General Commands Manual 					      SSH-ARGV0(1)

NAME
ssh-argv0 -- replaces the old ssh command-name as hostname handling SYNOPSIS
hostname | user@hostname [-l login_name] [command] hostname | user@hostname [-afgknqstvxACNTX1246] [-b bind_address] [-c cipher_spec] [-e escape_char] [-i identity_file] [-l login_name] [-m mac_spec] [-o option] [-p port] [-F configfile] [-L port:host:hostport] [-R port:host:hostport] [-D port] [command] DESCRIPTION
ssh-argv0 replaces the old ssh command-name as hostname handling. If you link to this script with a hostname then executing the link is equivalent to having executed ssh with that hostname as an argument. All other arguments are passed to ssh and will be processed normally. OPTIONS
See ssh(1). FILES
See ssh(1). AUTHORS
OpenSSH is a derivative of the original and free ssh 1.2.12 release by Tatu Ylonen. Aaron Campbell, Bob Beck, Markus Friedl, Niels Provos, Theo de Raadt and Dug Song removed many bugs, re-added newer features and created OpenSSH. Markus Friedl contributed the support for SSH protocol versions 1.5 and 2.0. Jonathan Amery wrote this ssh-argv0 script and the associated documentation. SEE ALSO
ssh(1) Debian Project September 7, 2001 Debian Project
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