Persistent Terminals For a Dedicated Computing Box? 288
Theovon writes "I just built a high-end quad-core Linux PC dedicated to number-crunching. Its job is to sit in the corner with no keyboard, mouse, or monitor and do nothing but compute (genetic algorithms, neural nets, and other research). My issue is that I would like to have something like persistent terminal sessions. I've considered using Xvnc in a completely headless configuration (some useful documentation here, here, here, and here). However, for most of my uses, this is overkill. Total waste of memory and compute time. However, if I decided to run FPGA synthesis software under WINE, this will become necessary. Unfortunately, I can't quite figure out how to get persistent X11 session where I'm automatically logged in (or can stay logged in), while maintaining enough security that I don't mind opening the VNC port on my firewall (with a changed port number, of course). I'm also going to check out Xpra, but I've only just heard about it and have no idea how to use it. For the short term, the main need is just terminals. I'd like to be able to connect and see how something is going. One option is to just run things with nohup and then login and 'tail -f' to watch the log file. I've also heard of screen, but I'm unfamiliar with it. Have other Slashdot users encountered this situation? What did you use? What's hard, what's easy, and what works well?"
screen (Score:5, Insightful)
Re:screen (Score:5, Insightful)
Screen is one of the greatest and useful commands ever envisioned.
Re:Quick primer (Score:5, Insightful)
the day that my grandmother is leaving persistent terminal sessions around is the day I pick up cross-stitching.
It's an advanced thing to do, why would it influence "linux on the desktop (tm)"
Here is where microsoft nailed it - remote desktop (Score:4, Insightful)
Microsoft's remote desktop simply works better than anything in the unix world. Screen is wonderful, but if you want to maintain an entire work session state across several locations, nothing beats RDP.
Why hasn't someone made an X server that uses RDP as the graphics device? Xnest is already 99% of the way there. I'd log in, and if I don't have a session it would create one, if I do have one it would reattach to that one, or maybe give me the option to create a new one.
I could use this in a 100% linux environment using rdesktop to connect to the server (instead of using xdm and Xnest, for instance). It would also work really well in a mixed windows/linux environment because I could use the windows remote desktop client to connect to a linux server and use X programs. Lastly, it would be great for POS applications because 99% of thin client systems already use RDP.
lets get cracking!
VNC is a "waste"??? (Score:3, Insightful)
I've used VNC routinely for this kind of purpose for years -- in fact, I do almost all my programming work using it. I have not found it to be a resource hog by any means. Just checking some of my VNC sessions now, resident memory use by the Xvnc process seems to stay between 20 and 60MB. At current memory prices, this is pretty much negligible (and I would assume you have plenty of DRAM on your compute box -- 8GB at least, yes?).
Others have mentioned SSH tunnelling -- I can assure you this is reliable; I've used it day in and day out for years.
Use Screen if you want, but personally I wouldn't even think twice about using VNC.
Re:SSH Tunnel to protect VNC (Score:3, Insightful)
Feeding trolls is always fun, so:
The idea is modularization. VNC does one thing, and does it (sort of) well. SSH does one thing and does it well in version 2. If you can't use SSH authentication in a setting, then you're still able to use VNC with some other auth mechanism. RemoteDesktop is inflexible and monolithic, if one component in the chain is a problem you have to abandon the whole solution. The modularity of *nix is it's strength, but it also makes things more difficult for novices. Windows is there for a reason - for people like you, who need things to 'just (sort of) work (with luck)'. Don't complain just because you think you can have your easy to use GUI cake and eat an extremely powerful implementation too. Developer man-hours are limited. They'll get to it when they have time away from their REAL jobs that PAY. Linux distros are so much more userfriendly these days because of many people willing to put hard work into it without reward, not because Blakey Rat sat around complaining on slashdot until someone got off their butt and started working on a trivially easy coding task.
Time for a car analogy: "This Minivan sucks. It can't go fast at all. The designers hate drivers, there's no other explanation." Well, a minivan is cheap and designed for carrying a lot of people. Pay more, get a better solution for your needs - Porsche.
Ok, I just compared Windows to a Porsche.