I have a one switch with four hosts connected to it. I want to keep a track of packets at each interface.
How can this be done using ONOS?
Keeping track of stats on OVS ports can be done through SNMP traps and off-host SNMP server. You don't need ONOS for that.
This wiki can be a good start.
Just type command "portstats" in ONOS CLI. And you can as well see in ONOS the GUI.
Related
I am looking for a basic thing yet I have not found not even a single good documentation on getting it done.
I want to allocate a floating IP, then associate it to a network interface of a droplet other than eth0.
The reason is I want to have the ability to very easily switch from one IP to the other with a programming language.
In a few words, I want to be able to do these two commands and both should provide a different response.
curl --interface eth0 https://icanhazip.com
curl --interface eth1 https://icanhazip.com
Also, I want to know what to do once I release the Floating IP, how do I roll back to the starting point.
All documentation I read, rely heavily on "ip route" and "route", most did not even work, some worked but replaced completely the old IP by the floating and that's not what I want, and also they did not show how to rollback the introduced configuration changes.
Please help, I spent 1 whole day now trying to get this to work for a project, and no results so far.
I guess there is no need to know DigitalOcean, how to make this work on other Cloud Providers would apply here too I think.
Update
After asking this on DigitalOcean community forum (https://www.digitalocean.com/community/questions/clear-guide-on-outbound-network-through-floating-ip), they claim that is not supported, although there may be some solutions to this if somebody can provide such a "hacky" solution I would take it too. Thanks
In the cloud (AWS. GCP etc.) ARP is emulated by the virtual network layer, meaning that only IPs assigned to VMs by the cloud platform can be resolved. Most of the L2 failover protocols do break for that reason. Even if ARP worked,the IP allocation process for these IPs (often called “floating IPs”) would not integrate with the virtual network in a standard way, so your OS can't just "grab" the IP using ARP and route the packets to itself.
I have not personally done this on Digital Ocean, but I assume that you can call the cloud's proprietary API to do this functionality if you would like to go this route.
See this link on GCP about floating IPs and their implementation. Hope this is helpful.
Here's an idea that needs to be tested:
Let's say you have Node1(10.1.1.1/24) and Node2(10.1.1.2/24)
Create a loopback interface on both VMs and set the same IP address for both like (10.2.1.1/32)
Start a heartbeat send/receive between them
When NodeA starts it automatically makes an API call to create a route for 10.2.1.1/32 and points to itself with preference 2
When NodeB starts it automatically makes an API call to create a route for 10.2.1.1/32 and points to itself with preference 1
The nodes could monitor each other to withdraw the static routes if the other fails. Ideally you would need a 3rd node to reach quorum and prevent split brain scenarios, but you get the idea right?
I have two services that are deployed in the two different VMs. I want to call one service from other to get some data via APIs. That should need to have an ultra-low latency call.
For that how can I used the Chronicle-Network (https://github.com/OpenHFT/Chronicle-Network)?
Or Any other solution?
I would suggest using Chronicle-Queue for passing messages from one service to another and back again. This is much lower latency than using TCP and easier to work with, provided the two VMs are on the same machine. You also get a record of every message making testing/debugging easier.
https://github.com/OpenHFT/Chronicle-Queue#high-level-interface-for-readingwriting
If you have two different machines I suggest either moving one VMs or using a low latency network card like Solarflare or Mellanox.
If you have a network call between VMs, try to use Chronicle Network.
Another option is Aeron UDP unicast connection - https://github.com/real-logic/aeron
I'm currently looking at options to allow me to build a remote COM-port solution.
The idea is to be able to access from my remote PC, another PC that's directly connected to a device locally via its serial COM-port.
I know that the obivous answer is to use a VPN between the 2 Internet connected PCs.
However, I need this solution to be as seamless to the end-user as possible.
i.e. no installing and configuring VPN software, etc.
So I was thinking that WebRTC would be great because the end-user can simply use their web-browser and not have to install any additional software.
My question is, is it possible to stream the COM port data between the 2 PCs via WebRTC?
If so, can you please point me in the right direction as to how I can go about achieving this?
Sorry if this is a ridiculous question, I'm very new to WebRTC, just exploring my options.
Thanks.
That should work great!
Networking wise you get NAT Traversal. That means the two computers can be in completely different networks, and still communicate. You may have to run a TURN server if P2P isn't possible.
Data wise you can exchange anything you want via data channels. It is datagram based and you can send/receive binary data. You get a callback telling you how much has been delivered, that way you can detect backpressure.
Are you ok with installing software on the remote host? You can do something like Pion WebRTC's data-channels. This shows you can have a browser connect to a Go process via WebRTC. Then use tarm/serial on the remote host to interact with the device.
If you want a browser on both ends there is the Web Serial API I haven't used it myself though. That locks you into only doing Chromium which might be an issue.
I'm in a need of network sniffer that attaches itself to a process in Windows 7 and sniff through it's networking like ... where it is sending packets to what the packets contain what packets it is receiving basically all the network traffic between that selected process and the server it is sending packets to.
I already downloaded tools like Rawcap and SmartSniff but they either don't work as intended or they throw some errors while trying to attach to the process.
I also tried wireshark but it sniffs my whole traffic not per process base
I know a freeware-Capsa Free which may cover your needs. But they request you to register to download. http://www.colasoft.com/download/products/capsa_free.php
So you are looking for something like Unix's 'strace' command :) Please find Microsoft Process Monitor here: http://technet.microsoft.com/en-us/sysinternals/bb896645.aspx , give also a try to xperf: http://msdn.microsoft.com/en-us/library/ff190983%28VS.85%29.aspx
Good luck! :)
I'm trying to figure out how to use winsockets to be able to turn my game into a LAN-playable game. I've read some winsockets documentation but I can't figure out how a client can get all the games that were created on LAN.
Does it have to try to 'connect' to each IP on LAN, like trying to connect to 192.168.0.1, then 192.168.0.2, etc? Is there a better way?
You would use broadcasting to advertise your servers on the LAN. Clients can then listen for these broadcasts to 'find' servers.
See here for more info:
http://tangentsoft.net/wskfaq/intermediate.html#broadcast
Typically these game servers use the local UDP broadcast, which is something that all clients receive and can process so long as they are listening to it.
Here is some sample client and server code I found that may be of interest to you: http://visual-c.itags.org/visual-c-c++/29424/
I think there are two possible ways to do this.
Make a "lobby" that clients and servers connect to so they can find each other through it.
Servers broadcast UDP packets. Clients listen and update a list of servers.
If you need a quick and easy way, the 2nd option would be great but remeber most of UDP packets will be wasted as they are used only once for each client.
The 1st option is more general and extensile solution to this problem. However, it might need more time to design and implement.
First off, I suggest that you get wireshark for any networking development. It will show you what packet goes through the wire. It will allow you to see how other games do it since there are many ways of doing this.
Using the UDP broadcast is one way of doing it. Simply change the target ip's last byte to 255 and you should be ok.