In VMWare, I have two virtual machines which are connected to each other through a named pipe. Can they communicate with that serial port or do I need to enable the network adapters ?
Configure VMWare to connect the serial port of one VM with the serial port of another. This is the virtual equivalent of plugging a null modem cable into the serial ports of two physical computers. Then, setup a null modem connection, where you network over PPP (Point-to-Point Protocol) just like the old analog modem days.
That said, why do you want to do this? Serial connections are very slow and are commonly used when a very simple, dumb, low level connection is needed. If you want to isolate traffic between two computers, create new virtual NICs on each and add them to the same, separate virtual subnet. This will be much faster, means you do not need to connect and disconnect over PPP and the existing VMWare management and monitoring tools work with it.
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I played a bit with the official dpdk by setting up the environment and running some example applications. Then I found out about the UDPDK which combined the DPDK with the UDP stack.
I already have set up the environment for UDPDK as per documentation and then ran the sample app 'pktgen' (both in the local VM and on the public server). Now as far as I understand, this project's aim was to send pure UDP packets between connected devices.
I tried to send UDP packets from VM1(using DPRK) to VM2(normal) and tried to receive packets through a normal UDP receiver (java app) and succeeded, Also was able to send from one server(using DPDK) to another server (normal & both servers are connected to same switch as I could arping between them)
Edit :
My next target / main goal is to send/receive UDP packets from/to 1 public server (using DPDK) to another public server (normal & they are not connected, and no control over switch). Then I came to know about Open vSwitch and been told that this can be the way though I saw DPDK-OVS being used between VM's mainly. Is it really possible to send/receive UDP packets from/to remote public server using DPDK-OVS and if so then how?
Thanks in advance for any help.
For the question can one send UDP packets between 2 servers which are remotely connected (not connected directly or through the switch); the answer is yes, one can do the same without any external or 3rd party switching applciation
Reason:
packets traverse through the local network using Ethernet and VLAN
packets traverse through the remote network using MPLS, IP address or tunnel protocols.
So as long a valid packet with ethernet, vlan, IP, UDP is constructed sending it locally or remotely is possible.
How to do it:
Ensure the port used supports VF
create a VF instance and bind to DPDK
use DPDK API such as pktmbuf_alloc, mtod, eth, IP, udp to create the desired packet.
send a packet on VF interface using tx_buffer or tx_burst.
As long as the right MAC address, VLAN and|or MPLS is right external routing is taken care.
If packets are travelled through the tunnelling via NAT, ip-in-ip or GRE|Geneve, then we have 2 options
Prepare the NAT, tunnelling in DPDK and send over a physical interface
send the custom packet from the DPDK application using TAP PMD into the kernel, using network IP route tables the packets will be forwarded with appropriate tunnelling.
The above second approach takes care of neighbour discovery and tunnelling overhead.
hence the use of DPDK-OVS or OVS or any virtual switch does not solve the underlying issue.
DPDK-OVS provides DPDK vhostuser/vhostuserclient type port as virtual (virtio) device to VM. to VM, the virtio device in VM is just like any other normal network device, the UDP applications runs on VM does not care what underlying network devices the VM runs, UDP receives/sends packet through Linux network stack. you could run another userspace stack on VM and UDP applications runs on top of the userspace stack to bypass VM Linux stack.
I have two devices, a PC and a RaspberryPi, that are connected to two different routers (one has VPN, one does not), that are connected to the same modem. (See diagram). The two routers are physically separated, so it would be difficult to connect them with a cable.
I am trying to access the RaspberryPi from my PC using SSH to run programs remotely on the Pi, and have the Pi send data that the program scrapes back to my PC for processing.
My question is, is this possible? And if so, how would I be able to implement it?
Thanks
I had this working (prior to my network reconfigure).
What I did was set router A as DHCP server.
Router B was configured as not to hand out IP Addresses.
Connect router A and router B on the LAN side.
All clients went through Router A, unless the devices' IP Settings were changed. I only changed gateway to router B to have the secondary connection.
I created two Qt apps: one client and one server.
I use them to send some data for handle a remote device.
If I am in localhost I haven't issues about them, but when i search to connect them by internet i don't know how to find correct Ip server to connect Socket Client.
How i can find this ip node?
Is there a class to find It?
you cannot find it automatically, if this is what you're asking about.
In real life you would deploy your server on some publicly accessible host, give it a domain name (important part as your host can change the IP address at any time) and connect the client via the DNS domain.
However if you're just playing around and you want to show to the world that your app works, specifying the IP address of the server in your client code would be perfectly fine (assuming you're running both the server and the client in the same network).
In that case, if you're running mac/linux run the command ifconfig (or just ip depending on the distribution). On Windows you can run the command ipconfig. Both windows and linux will give you a similar output resembling this:
Pay attention to the network adapters. There can potentially be many of them. You may have some emulated adapters if you have docker or VMWare, you may have the wireless adapters if you have a WiFi card, and then the ethernet adapters if your computer can connect to the the internet with an ethernet cable. Each of these adapters specifies a different IPv4 address. You want to pick the one that is connected to the same network as your client. So for instance if both your server machine and your client running machine are connected to the same wifi, you pick the address from the Wireless LAN adapter
I am trying to send data using the AsyncUDPSocket class. And I can send data using the iPhone simulator over the wire to another machine that is running a simple C-coded listening server. I can also receive data over the wire using a client connected to the simulator(server). However, when I tried the same over Wifi, using the simulator, I could only send data but not receive any data.
I read on another post, that unicast data makes this possible. How can I acheive this using AsyncUDPSocket?
Thanks,
Angelo.
Ok, I figured this out. A newbie kind of thing, really.
When I set my Mac network preferences to Ethernet, I get an IP for me to communicate. However, when I turn Airport(Wi-Fi for more newbies) ON, and ethernet cable disconnected, I checked my network preferences, and sure enough my IP address was a different one.
Spoke to a friend (an ace in networking) and the thing clicked immediately: On WiFi networks a DHCP server allocates an IP address. This IP address has to be reserved, at the very least, at the DHCP server. Since my IP was not reserved, I had to change the IP address, in my udp_client.c file, recompile and run the client to connect.
BTW, I can now communicate between my iPhone and my PC using my local WiFi (office) network.
For any who might face the same problem, do not be assured that the IP address of your mchine is the same, when you switch from LAN to Wifi, and use the device mostly for WiFi reated testing. :)
I have a laptop with the standard wireless and wired cards, I would like the host system to use the wireless connection and the vm machine to use the wired connection.
The point is that at the wired connection I can get a public, routable IP address, and I need that for my vm, while the host can work with the private IP.
You can assign any of your network cards detected by virtualbox to 1 of the 4 network cards you can put in the vm. See this for different modes