My company uses a third party product to manage subscriptions. The subscription database is set up on a server we control and we have four machines set up with the client application. Those four machines are the server machine and three others.
We are limited to four licenses, and the way the client application is installed is with different modules. The same machine is only supposed to consume on license, regardless of how many modules are open. It does this by supposedly pulling the net_address from the master..sysprocesses table. In theory, my company has enough licenses for all four machines to connect to the database, but one of my users is saying that they receive a notice that there are no further licenses available.
When I check the database, I notice that of the four machines, only one of the net_address's matches the hardware address (MAC) of my four machines that have the client application installed. I have confirmed no breaches, but I am not understanding where these net_address entries are coming from. The support team for the application insists that they should match the physical hardware(MAC) address, and with one of the client machines doing so that may be true, but I am not sure where these other addresses are coming from.
All the devices are behind the same router, so the MAC of the router shouldn't be coming in to play (and doesn't match any of the unknown entries), and none of the machines are behind any other L3 switch. They are connected via ethernet, and I am not seeing any installed applications that would cause MAC spoofing. The server machine itself is one of the devices with a net_address that doesn't match the MAC of the active NIC, and tracert only shows one hop.
What would be some other reasons that net_address wouldn't match the MAC of the connected client machine?
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I want to create a desktop application using vb.net and sql-server. I have two computers and I have my sql-server installed in one of the machines (server) in this case. I want to access the database from that (server) using another computer but the challenge is, I don't have any internet connection. All I have is a network cable to connect these two computers the one serving as a server and the client machine. Is this possible to access my database or can only be achieved over an internet connection? If possible how can I go about it?
Yes this is possible, if you only need to connect two computers, you'll not even need a switch or hub. You only need to assign both computers a private IP address in the same address space, such as 10.0.0.2 and 10.0.0.3 for computer A and B.
However, it might still be reasonable to use a switch for your purpose, as you might need to expand your network and/or connect to the internet in future cases, but in your particular case, it is not mandatory.
Sometime after last Thursday morning (3/5/2020), the product datasheet that I've been automatically generating and printing for years from a VBA-enabled Access database now comes out with the margins set way too small, turning an 8.5 x 11 printout into ~4 x 11 printout (print preview shows the same).
The kicker is that nobody else is seeing this problem (it's a shared database). I even asked my IT manager to log in using my username/password on a physical system there within the company network (I work remotely) and the printout looks completely normal. He also VPN'd in from his own laptop using his login and mine...no problems.
This problem occurs in each of the following scenarios:
-local front-end, server back-end when logged into company network through VPN from my laptop
-server front-end, server back-end when logged into company network through VPN from my laptop
-local front-end, local back-end (on my laptop) with VPN enabled or disabled
-local front-end, server back-end using a remote connection to the physical system mentioned above (where it worked for the IT manager under my login)
-local front-end, server back-end using a remote connection to a different physical system located within the company network
-local front-end, server back-end using a remote connection to a virtual machine located within the company network (logged in under a completely username/password)
All systems are completely up to date with the most recent Microsoft Windows and Office updates.
What could be going on here? What should I try next?
I'm sorry for my bad english.
There is a application with license tied to the hardware. One computer - one license.
Typically, a license check is as follows:
The application scans hardware.
The application collects information about the hardware and prepares a request for the license availability.
The application sends a request to check the availability of the license.
The license server receives the request and returns a response. The application receives a response from the license server and activates full functionality.
However, if the application is on the virtual machine - gathering information about the hardware fails.
I could not get information about the server hardware, as default methods do not permit do it.
Appeal to the hypervisor methods allows you to collect some statistics, but it is not enough to generate a request for the presence of licenses.
Thus there are 2 questions:
How within the virtual machine, I can get information about the
server hardware?
How can I implement verification of the license tied to hardware, if
the program is running on a virtual machine?
Thank you!
The guest OS and the hypervisor can communicate with each other through the VMware vSockets.
I want to communication between two different android phone via USB. I look at Google SDK guide I don't know how can i do.Somebody can give me some suggests ? Thank you very much !
The USB-Standard requires to work as host-client-mechanism. This means in particular, that you usually have a host-controller (for example inside your PC) which a client (USB-drive, MP3-player, mobile phone) can connect to.
The host is responsible for negotiating and establishing a connection. If you want to connect two clients with each other, one of them must Support USB-On-The-Go to serve as a host with limited capabilities.
From Wikipedia
The design architecture of USB is asymmetrical in its topology, consisting of a host, a multitude of downstream USB ports, and multiple peripheral devices connected in a tiered-star topology. Additional USB hubs may be included in the tiers, allowing branching into a tree structure with up to five tier levels. A USB host may implement multiple host controllers and each host controller may provide one or more USB ports. Up to 127 devices, including hub devices if present, may be connected to a single host controller.[20][21] USB devices are linked in series through hubs. One hub—built into the host controller—is the root hub.
Can someone explain what is the difference between X server and Remote Terminal servers in simple terms?
For example, Hummingbird Exceed is an X server and Citrix is a Remote Terminal Server. How do these servers work?
A terminal server runs at the "other" machine while you use a remote desktop client to view the other machine's screen.
A X server (of the X11 Window System) runs on your machine while another machine (or several thereof) send their output to your computer.
The most important difference to the end user is probably "culture": With the X Window system you typically work with windows that run on several hosts. (You often sit in front of a quite stripped down workstation, get one application from one computer, another one from another computer.) When working with X things feel very heterogeneous - a special application only runs on a HP workstation while your company is stuffed with suns or linux boxes? No problem, just buy one HP, everone can use that application over the network like as it was local.)
Remote terminal services feel more like another computer sends its complete screen to you, more like you have a 100-Mile-Long monitor and usb cable (with a little lag built in). You typically use a remote desktop client that sends a complete desktop to you.
However in recent times both techniques get close to another - windows remote desktop (which is based on citrix) can send only application windows to your desktop, while a lot of programs based on X11 are theoretically network transparent but practically need to run on the local machine. (Sorry, no 3D shooter over the network - an extreme example).
Which one is better? I don't dare to say. White X11 is a lot more flexible (it was designed with network transparency in mind - it makes absolutely no difference if an application runs local or remote - it is in many aspects more complicated. As long as there was no remote desktop sharing there was a clear advantage, but slowly the gap is closing, for example by terminal services now allowing you to do many things that were available with X11 only in earlier times.)
By the way, the main reason many X11 application still feel a little "snappier" over the network than windows counterparts is the thing that many application programmers on windows still think they always run local and dump a lot of bitmap graphics on the screen - like custom toolbars in ZIP tools. X11 applications did not do this for a long time and chose "ugly but fast" because X11 forces you to think about the network. But as X11 applications get more pretty and Windows programmers more aware about terminal services the difference will dwindle.
Oh and an important point: X11 is deeply ingrained in the Unix way of things, Citrix is mainly used on Windows (in the form of Microsoft's Windows Terminal Services - which originated in Citrix code). So lock a terminal services admin and a X11 operator into a cage and step back watching bloodshed when they figure out who they are locked in with ...
An X server most likely refers to the X11 windowing system, which is the GUI that most unix flavors (including linux) use. It's a client/server setup, and has been around for a very long time
A remote Terminal Server in the case of Citrix is a remote windows instance that can be connected to with a special Citrix client. The Citrix environments I'm familiar with are all MS Windows solutions, ie they work similar to X, but are for Windows Servers only
They both sort of operate in similar fashions, which is serving a remote client a windowing solution. IE, they both let a server run the actual application while the display of that application is sent back over the network to a client PC.
A 'Terminal Server', as it's called, basically allow you to connect to a Windows session remotely. They employ a bit of magic to make the experience snappy over connections with latency. The Windows GUI system isn't network transparent like X, so it took a while longer to get this feature. Windows Server 2008 and Citrix products have the ability to let you use a single application, unlike the traditional Terminal Server.
X is the GUI protocol for Unix/Linux. The X server accepts connections and displays their windows. The clients are actually the programs themselves. These clients can be local or remote, it doesn't matter to X. X just displays them as requested, on the local screen or over a TCP connection. This is lower level stuff than terminal servers, and allows graphical programs to run on one machine and display on another. X11 doesn't compress or encrypt the traffic like RDP does (although SSH can help you out there).
The linux equivalent of RDP is NX. They provide free software to run NX servers/clients. I've used it and it works pretty well.