How To Redirect The Error Message?

I have a hostlist and there are several hosts. I want to use ssh to connect to them. I want to see whether the host is available or not by the time length of ssh takes. If it take long than 5s (which means it is not available). Then stop it, and ssh to next host. Once a host is available, then output the name of host. I previously use nmap, but the IT security told it is not allowed to install it on the desktop on campus.
Code:

host_list="/home/campus27/zwang10/Desktop/cluster/program/hostlist"
HOSTS=`cat $host_list`
for line in $HOSTS
do 
timeout -5s `ssh $line`
done

The above script is all I can do.

I have many hosts as following. But those hosts are dual operating system (Linux and Windows). I always run program background. If someone is using Linux, it is fine. But if someone is using windows or the host is offline. Then, I cannot use ssh. The way I do preiviously is first ssh one by one. And then find the hosts which are offline or windows. And write them down one by one. And then ssh to hosts except them. Let us assume the number of programs is less than the total available hosts. Can someone write a shell script to output the all available hosts to a file like "host_available"?
Here is the host file.
https://www.dropbox.com/s/vbz6w864y3...tlist.txt?dl=0
I am using ssh to connect the computers on campus. If the computer I am trying to connect is offline or using windows, the ssh will take long time, and finally it will failed. I write a shell script to generate the hostlist
Code:

#!/bin/bash
for i in `seq -w 1 28`
do
echo "c15-0330-$i.ad.mtu.edu"
# I would like to add a command here to see whether ssh c15-0330-$i.ad.mtu.edu it succeeds or not. And then output a #file which contains the all available host.
done
for i in `seq -w 1 20`
do
echo "c28-0112-$i.ad.mtu.edu"
done
for i in `seq -w 1 20`
do
echo "c28-112a-$i.ad.mtu.edu"
done

I do not how to set a certain time to see whether connection is successful or not (see the comment in the shell script).

I am trying to login to my linux server. I was initially doing "ssh hostname". The login did not work, so I tried "ssh username@IP", which still prompted me with the yes/no prompt, but I received this error:

Code:

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that a host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
XX:XX...:XX.
Please contact your system administrator.
Add correct host key in /Users/user/.ssh/known_hosts to get rid of this message.
Offending RSA key in /Users/user/.ssh/known_hosts:5
RSA host key for 192.168.1.3 has changed and you have requested strict checking.
Host key verification failed.

Hi all,

I have a host#1 with ip=192.168.3.100 and a host#2 with ip=192.168.2.100. Both hosts are connected to some linux device with 2 interfaces : eth0 with ip=192.168.2.1 and eth1 with ip=192.168.3.1.

So host#1 is connected to eth1 and host#2 to eth0. I would like to ping host#2 from host#1 and vice versa. How can I do that ?

I tried :
echo 1 > /proc/sys/net/ipv4/ip_forward
iptables -A FORWARD -i eth1 -o eth0 -j ACCEPT
iptables -A FORWARD -i eth0 -o eth1 -j ACCEPT
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

but it didn't work

PS
This is my first post here, so please don't be very strict to me
Looking forward to hearing from anybody as I'm out of ideas...

BR,
Dmitry

Hello all,
I am trying to execute Code:

ssh $a@$b mkdir abc

in a shell script where, a and b are variables
a=username and b=server.ip
It is giving me an error Quote:
ssh connect to host port 22 connection refused
why am I getting the error?? ssh does not accept variables? Can anyone help.
Thanks in Advance

I have an expect script to SSH to a remote host and obtain some user inputs and information about the server/network configuration. The responses are saved in a text file that I then need to copy to my local host so that I can read the lines into variables for use in the parent shell script.

Is there a way to do this without needing to enter the username and password for the local host to use function scp? I have tried the following in my expect script to no avail:
Code:

spawn scp $usr@$host:$flnm .
expect {
	-re "(.*)assword:" { 
		send -s "$pswd\r"
	}
}

I have also tried to directly scp the file and enter the username and password to try to debug the issue, and that doesn't work either:
Code:

spawn scp file.txt user@host:file.txt
expect {
	-re "(.*)assword:" {
		send -s "password\r"
	}
	"you sure you want to continue connecting" {
		send -s "yes\r"
		exp_continue
	}
}

In both scenarios I have used exp_internal 1, and there are no errors. But I do not end up with the file on my local host.

Following the copy, I would like to delete the file from the remote host. Any suggestions on how to accomplish this?

Hi all,

Been reading on stdin, stdout and stderr and encounter 2 questions, hope gurus here can advise.

0 = stdin
1 = stdout
2 = stderr

Code:

Sun Dec 21 03:53:42 SGT 2014 > cat test5.sh
#!/bin/bash

echo "Please enter value for name :"
read name
echo "Your name is $name."

echo "Next echo will be a syntax error"
ehco

Code:

Sun Dec 21 03:53:46 SGT 2014 > test5.sh 1> output.txt 2> error.txt
Noob

Sun Dec 21 03:54:56 SGT 2014 > cat output.txt
Please enter value for name :
Your name is Noob.
Next echo will be a syntax error

Sun Dec 21 03:55:23 SGT 2014 > cat error.txt
/home/alan/scripts/test5.sh: line 8: ehco: command not found
Sun Dec 21 03:55:26 SGT 2014 >

Which so far all is good and the correct way to output everything including error to a single file is

Code:

Sun Dec 21 03:59:14 SGT 2014 > test5.sh > output.txt 2>&1

Q1) How is a command being interpreted in linux , the sequence in which it is interpreted ? from left to right ? right to left ?

Shouldn't it be

Code:

test5.sh 2>&1 1>output.txt 
or 
test5.sh 2>&1>output.txt ?

Regards,
Noob

I have just installed a new debian OS and want to change a file.
For some reason, gedit didn't come pre-packaged so I installed it with apt-get.

When I use a terminal as root, gedit won't open. I get the following error message:
Code:

gedit grub
(gedit:3679): EggSMClient-WARNING **: Failed to connect to the session 
manager: Authentication Rejected, reason : None of the authentication
protocols specified are supported and host-based authentication 
failed

Gedit will open page files on the desktop - but not on the terminal.
Is this because I haven't done something with the new install or should I remove gedit and reinstall?

Trying to set up Virtual Host on Ubuntu 14.04.

Any help to solve this is greatly appreciated!!!

Here is info:

Directory: /var/www/mydb.com/public_html (owner set to $USER:$USER)

Permissions: sudo chmod -R 755 /var/www/

Sample Page: /var/www/mydb.com/public_html/index.html (Shows Message)

Virtual Host Files:

Sites Available: mydb.com.conf
set ServerAdmin => admin@mydb.com
set ServerName => mydb.com
set ServerAlias => www.mydb.com
set DocumentRoot => /var/www/mydb.com/public_html

Sites Enabled: mydb.com.conf
ServerName mydb.com
ServerAlias www.mydb.com
ServerAdmin admin@mydb.com
DocumentRoot /var/www/mydb.com/public_html


I: disabled 000-default.conf w/a2dissite
enabled mydb.com.conf w/a2ensite

HOSTS File /etc/hosts:

127.0.1.1 localhost mydb.com
127.0.0.1 localhost
127.0.1.1 rick-Latitude-E6510

Result of localhost/mydb.com Same with www.mydb.com.

404 Not Found.
The requested URL /mydb.com was not found on this server.
Apache/2.4.7 (Ubuntu) Server at localhost Port 80

This from /var/log/apache2/access.log

127.0.0.1 - - [03/Apr/2015:13:19:08 -0700] "GET /mydb.com HTTP/1.1" 404 496 "-" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:37.0) Gecko/20100101 Firefox/37.0"

I have two VM's on a Redhat 7 Base machine and installed Redhat 6 on both machnies. Trying to use FTP. I can ping both each other.
VSFTPD is installed,
firewall is enabled.
vsftpd.conf is also updated for anonymous user login.
I could login using anonymous user.
while uploading file
I am getting a message as ftp: connect: no route to host