[X2Go-User] Is x2goserver available?

[Peter Brodsky]

Sorry to dampen the drama but...

Minisubs have been operating for many years with no computers whatsoever.
Or simple laptops running whatever version of Windows is compatible with 
the sonar display.
The important life-support stuff is partitioned away from all that. And 
Stefan, we can go offline to talk about
why losing the display would not impact our ability to exercise control.

Note that by "losing our primary control system" I meant any operational 
downtime (sitting in a warehouse)
while I load a new O.S. (not in the sub itself during a dive).

FYI:  AUVs have been using Linux as their primary command/control O.S. 
for years, the only competition being
Windows.  The old days of dedicated realtime OS's like VxWorks or custom 
bare metal apps are over, except
for military vehicles or maybe NASA - too expensive, too difficult to 
maintain.

Anyway - I'm upgrading to Mint 17.1 now, so hopefully that obviates the 
need to build the .deb package.

For those interested, here's a recent promo about the project:
     https://www.youtube.com/watch?v=ipAxZoMzFYk

Regards,
- Pete




On 01/07/2015 12:10 PM, Stefan Baur wrote:
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> Am 07.01.2015 um 17:42 schrieb Peter Brodsky:
>
> [...]
>
>> The network on which I'd run X2GO is completely private - a mix of
>> perhaps 3 Linux/Windows systems residing on a small submarine.
>> Could not see the wider world even if we wanted to, unless someone
>> figures out how to propagate RF through seawater.  So security is
>> not an issue.
> [...]
>
>> Given all the options... I'll look into upgrading to Mint 17.  This
>> is tricky given the application (losing our primary control system
>> computer for any length of time is a very bad thing), but perhaps
>> this is the best long-term solution.
> Oh. My. God.
>
> I sure hope you know what you're doing (well, at least
> http://www.apl.washington.edu/people/profile.php?last_name=Brodsky&first_name=Pete
> seems to indicate so ;-)) and have some sort of backup/emergency
> control/failsafe mechanism in place that can make this thing surface
> automatically if something goes, forgive me the pun, belly-up.
> Especially if it isn't an AUV but a manned submarine.  I'd probably be
> in for a new pair of pants and underpants if I heard the submarine I'm
> on is controlled by a plain off-the-shelf computer and not some
> sophisticated machinery with an trimmed down and hardened RTOS with a
> watchdog feature and a backup control system based on a different
> design in place.
> And that's not because I think X2Go is a crappy piece of software (I'm
> the X2Go Lead Evangelist after all, I tell people how fantastic X2Go
> is all the time), it's because I would never trust a regular operating
> system and off-the-shelf hardware for a task where human lives or some
> seriously expensive device like an AUV are/is at stake.
>
> That said, if you *do* get X2Go running in that environment, it would
> make for one heck of an entry on our success stories Wiki-page!  So if
> you do succeed, we'd absolutely love to hear back from you!
>
> So, back to the original problem - what does "xhost" say on your
> current Mint 15 machines?
>
> And while this isn't exactly X2Go-related - what does the partitioning
> of these machines look like?  If you have unpartitioned disk space, a
> partition you could spare (that's why I usually have a swap partition
> large enough to hold a small Linux installation, when changed from
> swap to ext, on my machines), or you are using LVM and have sufficient
> free space in there and a boot loader that supports booting from a
> logical volume, you might want to look into using debootstrap to
> install a newer version of your operating system into the available
> space, while your current installation is booted.  Or, if debootstrap
> isn't available for Mint, do a Mint 17 install on another computer,
> tar the image, transfer it to a new partition/LV on the Mint 15
> machine, and see if you can boot into it.  That should minimize downtime.
>
> Feel free to contact me off-list for some options/best practices.  My
> company eMail address is kontakt at baur-itcs.de.
>
> I can't claim any previous experience with submarine control systems,
> but we do have quite a few Linux computers spread across Germany in
> more or less remote locations (there's even one that, according to the
> staff that's been on-site once to install the machine, can only be
> reached via horse drawn sleigh or snowmobile during the wintertime)
> where we do need to run upgrades with minimum downtime, and having
> someone on-site to perform the upgrade is usually not an option (and
> where it is, it tends to get expensive rather quickly), so we've come
> up with a few things to avoid that.
>
>
>> At the same time - Mike I'll take you up on your offer to build a
>> Debian package for me.  I am familiar with Git, of course, but have
>> not built .deb packages.
> Usually, this is the place where I would point out that we do have
> commercial support offerings for customers with needs like that one
> (I'm sure someone would usually offer to build you packages even for
> Mint 15 if you paid for it) - but in your case, I would actually have
> to check back with our developers if anyone is willing to offer
> commercial support or if they're all too worried about liability
> issues in case a bug in the code causes you to lose control over the
> AUV/submarine ... drowned customers aren't happy customers, if you
> know what I mean. ;-)
>
> - -Stefan