Scenario: The ship has a linux computer, you want a desktop screen capture that you can view on your own local computer.
Names:
## landuser@landserver must be able to ssh into shipuser@shiplinux Set up a ssh key so this is automatic.
## me@mycomputer must be able to ssh (with a key) into landuser@landserver
Make a bash script that looks like this:
## begin remote_screenshot.bash ##
#!/bin/bash ## store the image in ~/tmp ## image will be called "screenshotX.png" cd ~/tmp; DISPLAY=":0.0" import -window root screenshotX.png ## give a clue echo "on ship: desktop captured in ~/tmp/screenshotX.png"
Make it executable and test:
remote_screenshot.bash
And view the figure it made: ~/tmp/screenshotX.png
And on the landside server, make this script to execute screenshotX.png on the ship, and rsync the file back. Call this one remote_shipX_screenshot.bash
## begin script to get the screenshot back to the landserver ##
#!/bin/bash ## works best if there is an ssh key on the remote machine # - make the remote command for screenshot # - this example requires a port to log in ssh -p ##### shipuser@shipserver /path/to/remote_screenshotX.bash ## bring it back, put it in /tmp echo "bringing back the screenshot" rsync -Pv -e 'ssh -p 56565' shipuser@shipserver:tmp/screenshotX.png /tmp ## move it to the location of choice mv /tmp/screenshotX.png /path/to/server/shipX/shipuser_screenshotX.png
Test it by running
/path/to/scripts/remote_shipX_screenshot.bash
and view the png
Now if you are on the landserver you can look at the png file. If you want the png served up on a web location, you can look at it directly. If you want an html to wrap it, so it refreshes every so often, put this in the same location as shipuser_screenshotX.png:
shipuser_screenshotX.html
##begin html file to display shipuser_screenshtX.png ##
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html><head> <meta http-equiv="Refresh" content="300"> <title>ShipX Desktop</title></head> <body> <img src="./shipuser_screenshotX.png" style="width: 100%"/> <br> <br> <br> </body></html>
Then you can browse to this page and it will refresh every 5 min: http://shipserver/path/to/shipX/shipuser_screenshotX.html
Make the landuser@landserver have a crontab entry to run the program hourly at 10 min past the hour.
NOTE: crontab does not have a good environment so if you need to set your PATH, do so in a bash_env file and source that before running the command. That's how I did it. Or be very explicit about setting your PATH first.This is all one line:
10 */1 * * * (date +\%F\ \%T; cd /path/to/myenv; . ./bash_env; /path_to_script/remote_shipX_screenshot.bash) >> /path/to/logfiles/shipXscreenshot.log 2>&1
Another note: I also outputted the stdout to a log file.
ssh landuser@landserver /path/to/scripts/remote_shipX_screenshot.bash
or make an alias:
alias get_shipX_screenshot='ssh landuser@landserver /path/to/scripts/remote_shipX_screenshot.bash; echo o "view this file"; echo "";echo http://shipserver/path/to/shipX/shipuser_screenshotX.html'
*Special thank you to Jules Hummon for providing steps/codes above.