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Full Discussion: While loop is causing ssh command to exit from script after first iteration.
Top Forums Shell Programming and Scripting While loop is causing ssh command to exit from script after first iteration. Post 302949543 by kchinnam on Monday 13th of July 2015 03:26:03 AM
Old 07-13-2015
Don, usually I would be scared to try </dev/null(empty stuff), but I tried, its working,, how is it telling ssh not to use same file descriptor to read serverList?

Aia, changing file descriptor is not working for me..
Code:
#!/bin/bash
while read -u12 server; do
        ssh $server uptime
done 12 < serverList

output:
./test.sh: line 4: syntax error near unexpected token `12'

ssh -n is working for my current script. But I do see myself using ssh in a interactive manner and enter passwords to remote server login.. in that case I guess while can't be an option..

Interestingly when I replaced while with for loop, its working fine.. since my input is simple I can afford, but this is not the right way for complex inputs.

Code:
for server in $(cat $serverList); do
        ssh $server uptime
done

How can tell ssh not to read from serverList file? -u12 trick is not working on SuSE linux 11 I am using..
Last edited by kchinnam; 07-13-2015 at 05:07 AM.. Reason: clarifying
 

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LEARN ABOUT NETBSD

rpc.yppasswdd

RPC.YPPASSWDD(8)					    BSD System Manager's Manual 					  RPC.YPPASSWDD(8)

NAME

     rpc.yppasswdd -- NIS update password file daemon

SYNOPSIS

     rpc.yppasswdd [-d directory] [-noshell] [-nogecos] [-nopw] [-m arg1 [arg2 ...]]

DESCRIPTION

     rpc.yppasswdd must be running on the NIS master server to allow users to change information in the password file.

     The options are as follows:

	   -d directory    Change the root directory of the password file from ``/'' to directory.  It is important to create the binary database
			   files (pwd.db and spwd.db) when using this switch or the password change will fail.	The databases need to be created
			   only once with the following command:

				 pwd_mkdb -d directory directory/etc/master.passwd

	   -noshell	   Don't allow changes of the shell field in the passwd file.

	   -nogecos	   Don't allow changes of the gecos field in the passwd file.

	   -nopw	   Don't allow changes of the password in the passwd file.

	   -m arg1 [arg2 ...]
			   Additional arguments to pass to make in /var/yp.

FILES

     /etc/passwd
     /etc/master.passwd

SEE ALSO

     chpass(1), passwd(1), hosts_access(5), nis(8), ypbind(8), ypserv(8)

AUTHORS

     Mats O Jansson <moj@stacken.kth.se>

BSD
								 February 26, 2005							       BSD
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