First, I'm not a R/RStudio user at all. I'm a Windows admin with the task to configure R and RStudio on a multi-user Citrix environment. To identify users between the multiple sessions, we are using the Palo Alto Terminal Server agent which will allocate a range of ports for each user and use them to identify each users. That's then used to give limited and specific access to resources for each users.
The problem is that the TS Agent also intercept the localhost connection that's created when you start RStudio (process rsession) and RStudio then cannot connect to R. One possible solution to solve this problem is to have control on the ports used when this local session is started.
I have made multiple research on the Internet but I have been unable to find if/how you can change the ports that are used. I have found different config files but none that seem to allow me to fix a single port or a port range.
Any insights on the way to fix the ports for the rsession process so I can better control them? Or another way to look at the problem: do you know the port range used by R/RStudio when they communicate together through the rsession? I can simply avoid using these range with the TS Agent.
I have only skimmed through the RStudio Source code, but it seems that the port is assigned randomly:
https://github.com/rstudio/rstudio/blob/bcc8655ba3676e3155d80296c421362881340a0f/src/node/desktop/src/main/application.ts#L226
However, it also seems like there is a startup parameter --www-port to set the port:
https://github.com/rstudio/rstudio/blob/bcc8655ba3676e3155d80296c421362881340a0f/src/node/desktop/src/main/session-launcher.ts#L592
I'm currently using AutoHotKey to create a variety of macros. I have two desktops side-by-side in a private (home) network. It is my desire to have the AHK Run command on PC1 make some sort of call to PC2. Both PCs are running Windows 10 (non-domain), and both use the same login credentials (same account via microsoft.com).
What I've tried: I have tried a few things, such as WMI, WinRM, schtasks. Each of these options work when dealing with non-interactive scripts. I am trying to call scripts that a) open GUI windows or b) send key strokes to PC2.
Other requirements:
The solution cannot require the password to be type in a prompt nor provided in the command-line call. The desired effect is that I press a button on my keyboard -> ahk command triggers -> script on PC2 is called.
As this network is shared with roommates (and whoever they allow to connect to our wifi), basic security is still a necessity.
This is not a language specific question - I am looking for the simplest/easiest/cleanest method. Thanks for reading.
Try a remote access connection app like TeamViewer. They allow you to control one PC from another across a network. https://www.teamviewer.com/en/
I have an astronomical observatory in my yard with four computers connected to all the observatory equipment. These four computers are controlled over my home network from one PC in the house.
The remote access app allows you to run an .exe on another computer which in my case is usually a compiled AHK script.
I have a number of tasks that require several PC's. A script running on the main PC will start secondary scripts on the observatory PC'c which in turn will send messages back and forth by sending text files to each others shared files. The PC receiving the text file will perform a specific action based on the message.
Here's a link to the observatory startup procedure. I a startup script on the main PC which turns on all the observatory equipment then starts a secondary startup script on each of the observatory PC's to load and position all the software and then connect all the cameras and associated equipment.
https://www.youtube.com/watch?v=UN4VoOKOcXo&feature=youtu.be
This just shows how the various scrips running on the observatory PC's load and position all the various app windows. Not exactly what you may need but it may give you some ideas about what you can do with the remote access software.
Lorence
I'm using WireShark to capture network information for a little network analysis project. One of the things I would like to do is look at what files have been accessed on shared drives (that is, using the SMB protocol).
Is it possible to recover the full path name (e.g. \server\path\to\file.txt) from only the captured packet? Based on this resource, the fourth packet should contain the UNC path name, but I'm not finding it anywhere in the captured session.
If it's not possible to recover the full path from the packet alone, is there some other way using hte information in the packet? I know, for example, that the packet contains the source IP and a file ID generated by source. Are those helpful?
Thanks
You dig it in the wrong place.
You should gather and log that information within Samba Server.
If you consist to do that analyze with sniffering software, then you have to reconstruct SMB session.
P.S. To be more specific , you need to recover all previous requests to subdirectory tree. If you need to recover \server\path\to\asdf1\file.txt, then you have to find requests to directory "to" first, also to directory "asdf1" too. Directory is a file itself, with attribite D.
So, I've taken a handful of programming courses(object-oriented, web) but never had "hands-on" projects where it's outside of coding.
Now I'm trying to figure out what these SSH stuff is about, I can't even figure out which client to use, so picked filezilla for now.
My question is, where can I read more about these terms like ports, and whatnots, in a way so I'm not learning aimlessly.
Thanks!
Basically, SSH is a way to command another computer exactly what to do over the Internet. You can execute any commend the remote system has, and your user has permission for.
The Internet
The Internet runs on a series of protocols collectively named TCP/IP. TCP/IP defines a way to find and address individual computers (IP) and a way to communicate between them (TCP).
You can think of computers on the Internet as a large collection of office buildings all close together. Each office has the exact same number of windows: 65535. Offices (computers) communicate by stringing channels between windows (ports). Each channel has two ends, called sockets. Each socket is associated with a port on the respective computer. We send data back and forth, and then the connection is closed.
Client/Server
There are two types of computers on the Internet: clients, and servers. Clients request information, and servers provide it. Ports 1-1024 are reserved for servers, 1 port per protocol. The full list is here, and as you can see, it is not without contention.
Let's say you visit a website
Your browser, the client program, sees that you typed "stackoverflow.com", and using DNS, discovers that stackoverflow.com is computer number 64.34.119.12. This is it's IP address. It allows your computer to find the network stackoverflow.com is located in, route to it, and establish a connection to the Stack Overflow web server. The web server is a program that accepts client requests from a browser like yours.
They speak in a protocol called HTTP - it allows your browser to request a page determined by a URL. The server sees the request, runs a program to construct a web page (or retrieves an HTML file, image, or any other file), and sends the result back to the browser. Port 80 has been reserved for HTTP. That means, your computer chooses a random port to connect from, and connects to port #80 on the server.
Unix and the shell
The majority of the Web (The Internet, even) runs on an OS called Linux (a Unix variant), instead of something like Windows. Unix systems possess a command-line interface, running a program called a "shell", which is a direct interface to the system. The shell accepts input, one command at a time. You type text in, and it spits out the out put of the command.
Secure Shell
SSH allows you to do this securely. All data traffic is encrypted using a well-studied published "public-key" cryptographic system. (In fact, it was major news when a vulnerability was discovered in a supporting encryption scheme, see these advisories).
SSH is a protocol commonly running on port 22. Anyone with a computer on the Internet (not behind a firewall) can run an SSH server, and allow users to connect to it and execute commands.
The majority of systems administrators and software developers using Unix on the server use SSH to configure, control, and upload programs to that server (located in some data center somewhere).
More
There are many many more details to all of this. Any term or acronym above can be typed into Wikipedia for pretty comprehensive information. There are plenty of books on Unix, Networking, and Web programming.
SSH is originally a secured replacement for telnet. The need for SSH arose from the fact that telnet does not support encryption and therefore everything (commands, output and password) was plainly visible on the network for all to see.
Because in the beginning SSH encryption (based on key exchange) was supposed to be strong (and it was indeed a marked improvement), and was open source, it took off rapidly and several extensions to the protocol were added, especially in the domain of remote file manageent and transfer.
In addition, SSH is used in tunelling and port forwarding configurations.
In the domain of file copy there are several options.
SCP: cp (copy). Inspired by rcp, an early file transfer extension to ssh.
SFTP: SSH File Transfer Protocol, a newer SSH extension to support File copy and browsing (but not really like FTP with 2 ports). It is more feature rich than both scp and ftp. Think of it as a remote file system protocol (however, however somewhat slower than scp).
FTPS: FTP over TLS/SSL. Needs 2 ports like ftp, one for command and one for data. Both connections can be encrypted.
Secure FTP. Real FTP tunelled over SSH.
The site to which you will need to connect probably offers SFTP. You just need to declare the remote server connection configuration in Filezilla site manager. You will need to provide the server ip address or name, the SSH server port, usually 22 but there are other possibilities (you should have been provided with this info) and select sftp as server type). When the connection is established, accept the public key and that should be it.
You can then drop your devs on the remote server.
OS choice
You shall first make a kind of choice between 2 worlds (MS or Linux).
Provided that the Linux community is somehow significantly less reluctant to share explanations. Also you will loose less time by choosing one or the other one, avoiding to wonder the same questions twice, with different answers depending on which OS you chose.
I experienced both, starting to search for solutions in the MS world, that I knew. Big mistake, loss of time. Then I changed, too late, to the Linux world. So I would advice to go straight to the linux OS for learning. Really many distributions for this. I would advice Debian (opened, user friendly, simple, safe, huge community) but you'll get as many proposals as there are admin.
OS understanding
http://www.linuxfromscratch.org/lfs/
http://www.ibm.com/developerworks/library/l-bash.html
http://tldp.org/LDP/abs/html/
Specific Questions about SSH
It depends a lot on the system you will choose but you could easily build a small client and a small server, then configure both and use ssh. Your 2 servers could even be hosted on the same machine, locally if you wish. Then you will learn how to set up the ssh-client side (often called ssh_config) and the ssh server side (often named sshd_config, with "d" standing for daemon).
Here you can find explanations about ssh for both worlds :
http://support.suso.com/supki/SSH_Tutorial_for_Linux
Some keywords for your google searches
List_of_TCP_and_UDP_port_numbers
ssh-keygen : encrypted keys (private/public),
ssh-add ssh agent
Gentoo keychain
and later but soon if you administrate your server on your own
The two main ones :
1) iptables
You may start with this and then go further with that one
2) fail2ban
this is a complement tool for which you'll find easily plenty of docs
...
Have fun :-)
EDIT: you can easily experience a Linux machine hosted in a windows OS, using virtualization (virtualbox, vm-ware..). It's a safe start and offer a good payback for this time investment. It would allow you to host as many machines (for example one linux server and one linux client) as you wish, in the limits of your HD room.
I assume you need to learn shell scripting. I recommend this book.
Filezilla is a FTP client. Try Putty - free SSH Client. And of course you need Linux server.
If you want to learn about SSH in depth then may I advise you this book SSH: The Secure Shell The Definitive Guide
See here for more info: http://www.snailbook.com/
I've read the book and learned really a lot. It teaches you all about setting up servers, clients, key agents and various (practical) applications.
When using socket in the UNIX domain, it is advisable to use path name for the directory directory mounted on the local disk. The UNIX domain only allows interprocess communication for process working on same machine.
Can you please explain the above line? It is about a socket in the UNIX DOMAIN.
Thanks!
A Unix domain socket or IPC socket (inter-process communication socket) is a data communications endpoint that is similar to an Internet socket, but does not use a network protocol for communication. It is used in POSIX operating systems for inter-process communication. The correct standard POSIX term is POSIX Local IPC Sockets.
Unix domain connections appear as byte streams, much like network connections, but all data remains within the local computer. UNIX domain sockets use the file system as address name space, i.e. they are referenced by processes as inodes in the file system. This allows two distinct processes to open the same socket in order to communicate. However, the actual communication (the data exchange) does not use the file system, but buffers in kernel memory.
In addition to sending data, processes can send file descriptors across a Unix domain socket connection using the sendmsg() and recvmsg() system calls.
The end-points of UNIX domain sockets are represented by files in the file system (instead of by host / port).
However the communication between processes is done within the local system and does not result in a seekable file getting stored anywhere.
The advantage of using the file system as the namespace for the end-points is that normal file permissions and ACLs can be applied - if you can't open the end-point you can't connect. IP sockets have no such mechanism.
It means that if you create a AF_UNIX socket on a NFS disk which is shared between two machines A and B, you cannot have a process on A writing data to the unix socket and a process on B reading data from that socket.
The communication happens at kernel level, and you can only transfer data among processes sitting in the same kernel.