retrieveHosts.sh

# retrieveHosts.sh
# Available host file retrieving script
#
# Description:
#   This script tries retrieving the list with available hosts from different hosts.
#   If succesfull the script will place the host.txt file at ~/recieved/
#   This script needs hostsToTxt.sh to be located at ~/scripts/ in order to function
#   This scripts supposes you are using an ssh-agent
#   If not this might also work but you will be typing your password a lot.
#   Easily setting up an ssh-agent can be done with my other script init_ssh-agent.sh.
#
# Version:  1.0
# Author:   Dieter Castel
# License:  Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License
#           See: http://creativecommons.org/licenses/by-nc-sa/3.0/ for more info.

# Variables:
#   Place of the hostsToTxt.sh script. You can edit it if you want to move the script.
scriptpath=~/scripts/hostsToTxt.sh
#   Output directory of the script.
outputdir=~/recieved/
#   List of the hosts that will be tried. You can expand this if you want more redundancy.
possiblehosts=(ham genk herent mol zwalm)
#   Boolean that tells the script if it failed all the hosts.
failure=true


# Make the recieved directory.
mkdir $outputdir

# Iterate over all the possible hosts.
for currentHost in $possiblehosts;
do
    echo "Will try ssh/scp with login $USER @ $currentHost"
    # Try to run the hostToTxt script on the currentHost.
    if ssh  "$USER"@"$currentHost".cs.kotnet.kuleuven.be 'bash -s' < "$scriptpath";
    then
        # If succesfull transfer the file from the host to the current machine.
        if scp "$USER"@"$currentHost".cs.kotnet.kuleuven.be:/home/"$USER"/toSend/hosts.txt "$outputdir";
        then
            # If the transfer succeeds the script succeeds and we break out of the for loop.
            failure=false
            echo "hosts.txt succesfully transferd from $currentHost to $outputdir"
            break;
        else
            echo "$currentHost failed to transfer the file";
        fi;
    else
        echo "$currentHost failed";
    fi
done

# Report failure
if $failure; then
    echo "Every try failed";
fi