How to download files using OFF (Owner Free File System) P2P? - p2p

I am testing P2P apps. I have downloaded OFF (Owner free Filesystem) P2P from the below link:
http://sourceforge.net/projects/offsystem/files/OFF%20System/
But I am unable to download any files using this client. I am not getting error messages even. I have referred following link also.
REF:
http://www.ghacks.net/2009/04/10/p2p-the-owner-free-file-system/
Please suggest some ideas if any of you used this OFF system.

From what I recall, the program ships with a list of bootstrap nodes. Chances are as active development ceased (at least as far as I am aware) many years ago that none of the bootstrap nodes are online.
I doubt that you will be able to get the network to function as there are unlikely to be any other nodes still running.
If you were to set-up a cluster of VM's running the software, it should be possible to set a bootstrap node in the config somewhere, once it has a connection, it will retrieve a list of other nodes that it can connect to.

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node.js on shared server space

I am playing with node.js and angular for first time. I use shared server hosting space. I am trying to get some node.js tests running.
CPanel seem to provide interface to deploy node applications. Example:
application url: myurl.com
application root: node-hello-world
application startup file: app.js
This seems to create directory and some artifacts in
/home/myurl/nodevenv/node-hello-world/6/bin
I have (limited?) shell access through Cpanel emulation, however I get error on source command.
source activate
got error: error: jailshell: fork: Cannot allocate memory
Does this mean node.js is installed and ready to run? Do I have to upload project as well? Where to? Trying to find more info on process of deploying to this type of server if possible.
sorry for nooby question.
Googling your error message, I came across this thread -- which admittedly is very old, but it's from cPanel and has the following comment from an administrator at the time:
Jailshell is a constrained environment by design. It is not meant to be a replacement for a full-featured, unrestricted, shell environment, such as is provided by Bash. If your user's need such full-featured environments then perhaps they need full shell access, or another method whereby they can accomplish their goal.
That answer was given in 2006 (yes, 13 years ago) but I have to imagine the spirit of that response is still true.
To be perfectly honest, I'd be afraid to use any shared hosting provider that would give you more than very limited shell to use -- it opens the door to many security vulnerabilities, and if multiple customers are in the same runtime (i.e. shared hosting) it could be catastrophic. Maybe your host does allow this, or maybe what you're describing isn't actually the same thing I'm referring to... you didn't offer a lot of details on this point.
Back to your question: Does this mean node.js is installed and ready to run? Do I have to upload project as well? Where to?
If I had to guess, Node probably isn't installed (it isn't in most shared hosting providers) -- but I can't say for sure based on the information you provided. My recommendation would be to call their customer support. Or pay for a dedicated hosting account where you get root access. Or just use something like Heroku.

What is the best way to set this working environment for my research group?

We recently got a supercomputer (I will call it the "cluster", it has 4 GPUs and 12-core processor with some decent storage and RAM) to our lab for machine learning research. A Linux distro (most possibly CentOS or Ubuntu depending on your suggestions of course) will be installed in the machine. We want to design the remote access in such a way that we have the following user hierarchy:
Admin (1 person, the professor): This will be the only superuser of the cluster.
Privileged User (~3 people, PhD students): These guys will be the more tech-savvy or long-term researchers of the lab that will have a user defined for themselves at the cluster. They should be able to setup their own environment (through docker or conda), remote dev their projects and transfer files in and out of the cluster freely.
Regular User (~3 people, Master's students): We expect these kind of users to only interact with the cluster for its computing capabilities and the data it stores. They should not have their own user at the cluster. It is ok if they can only use Jupyter Notebooks. They should be able to access the read-only data in the cluster as the data we are working on will be too much for them to download it locally. However, they should not be able to change anything within the cluster and only be able to have their notebooks and a number of output files there which they should be able to download to their local system whenever necessary for reporting purposes.
We also want to allocate only a certain portion of our computing capabilities for type 3 users. The others should be able to access all the capabilities when they need.
For all users, it should be easy to access the cluster from whatever OS they have on their personal computers. For type 1 and 2 I think PyCharm for remote developing .py files and tunneling for jupyter notebooks is the best option.
I did a lot of research on this but since I don't have an IT background I cannot be sure if the following approach would work.
Set up JupyterHub for type 3 users. This way we don't have to have these guys to have a user at the cluster. However, I am not sure about the GPU support of this. According to here, we can only limit CPU per user. Also, will they be able to access the data under Admin's home directory when we set up the hub or do we have to duplicate the data for that? We only want them to be able to access specific portions of data (the ones related to whatever project they are working on since they sign a confidentiality to only that project). Is this possible with JuptyterHub?
The rest (type-1 and type-2) will have their (sudo or not) users at the cluster. For this case, is there UI to workaround so that users can more easily transfer files from and to the cluster (that they don't have to use scp)? Is FileZilla an option for example?
Finally, if the type-2 users can resolve the issues type-3 users have so that they don't have refer to the professor each time they have a problem. But afaik, you have to be a superuser to control stuff at JupyterHub.
If anyone had to setup this kind of an environment at their own lab and share their experiences I would be grateful.

How does RunKit make their virtual servers?

There are many websites providing cloud coding sush as Cloud9, repl.it. They must use server virtualisation technologies. For example, Clould9's workspaces are powered by Docker Ubuntu containers. Every workspace is a fully self-contained VM (see details).
I would like to know if there are other technologies to make sandboxed environment. For example, RunKit seems to have a light solution:
It runs a completely standard copy of Node.js on a virtual server
created just for you. Every one of npm's 300,000+ packages are
pre-installed, so try it out
Does anyone know how RunKit acheives this?
You can see more in "Tonic is now RunKit - A Part of Stripe! " (see discussion)
we attacked the problem of time traveling debugging not at the application level, but directly on the OS by using the bleeding edge virtualization tools of CRIU on top of Docker.
The details are in "Time Traveling in Node.js Notebooks"
we were able to take a different approach thanks to an ambitious open source project called CRIU (which stands for checkpoint and restore in user space).
The name says it all. CRIU aims to give you the same checkpointing capability for a process tree that virtual machines give you for an entire computer.
This is no small task: CRIU incorporates a lot of lessons learned from earlier attempts at similar functionality, and years of discussion and work with the Linux kernel team. The most common use case of CRIU is to allow migrating containers from one computer to another
The next step was to get CRIU working well with Docker
Part of that setup is being opened-source, as mentioned in this HackerNews feed.
It uses linux containers, currently powered by Docker.

Accessing Matlab MDCS Cluster over SSH

I just installed Matlab's Distributed Computing Server on a bunch of machines and it works, but only for those physically connected to the cluster's network. For remote access those machines are 2 SSH hops away. How this problem is usually solved? I thought in setting up a VPN, but to me this seems like last resort.
What I want is that everybody in the lab, using their own versions of Matlab, with the correct Toolbox, just run their code in the cluster somewhat effortlessly. I guess I could ask to everybody just tar-ball their files and access a remote installation of matlab, somehow forwarding the GUI session (VNC or X-Forward), but that seem ugly.
Any help?
It is possible to set up "remote access" to a cluster running MDCS so that clients without direct access can submit jobs there. The documentation for this starts here:
http://www.mathworks.com/help/mdce/configure-parallel-computing-products-for-a-generic-scheduler.html
I'm not quite sure how to configure things so that the submission can work across two SSH connections - the example integration scripts shipping with MDCS all presume only one. However, it should be possible providing that:
The client can put the job and task files somewhere the execution nodes can see them
The client can trigger the appropriate qsub or whatever on the cluster headnode
You might also consider simply contacting MathWorks installation support.

Collectd server not writing down received client data

I have pretty strange problem with Collectd. I'm not new to Collectd, was using it for a long time on CentOS based boxes, but now we have Ubuntu TLS 12.04 boxes, and I have really strange issue.
So, using version 5.2 on Ubuntu 12.04 TLS. Two boxes residing on Rackspace (maybe important, but I'm not sure). Network plugin configured using two local IPs, without any firewall in between and without any security (just to try to set simple client server scenario).
On both servers collectd writes in configured folders as it should write, but on server machine it doesn't write data received from client.
Troubleshooted with tcpdump, and I can clearly see UDP traffic and collectd data, including hostname and plugin names from my client machine, received on server, but they are not flushed to appropriate folder (configured by collectd) ever. Also running everything as root user, to avoid troubleshooting permissions.
Anyone has any idea or similar experience with this? Or maybe some idea what could I do for troubleshooting this beside trying to crawl internet (I think I clicked on every sensible link Google gave me in last two days) and checking network layer (which looks fine)?
And just small note: exactly the same happened with official 4.10.2 version from Ubuntu's repo. After trying to troubleshoot it for hours moved to upgrade to version five.
I'd suggest trying out the quite generic troubleshooting procedure based on the csv and logfile plugins, as described in this answer. As everything seems to be fine locally, follow this procedure on the server, activating only the network plugin (in addition to logfile, csv and possibly rrdtool).
So after no way of fixing this, I upgraded my Ubuntu to 12.04.2 LTS (3.2.0-24-virtual) and this just started working fine, without any intervention.

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