I have deployed multiple open vswitches each deployed on a virtual machine (one switch for one machine).
I would like switches to communicate among themselves.
I have gone through few posts regarding gre or vxlan tunneling. I have tried those steps but of no use. Especially when ever I try to make the ovs as "dhclient" it goes into kind of infinite loop. The command never executes.
Can anybody please share your experience on how open vswitches should communicate when deployed in virtual machines.
Thanks
Related
I have a series of RPi's running Raspian which need to deployed in various location around the world.
They will have internet access, but will all be behind a router. Is there an off-the-shelf solution to keep the possibility to create a SSH connection to them? I am thinking about solving problems, upgrading etc.
I am thinking of a 'server' solution where a 'client' on the RPi keep an active connection so a SSH connection can be established when required. Any suggestions will be much appreciated!
I have experimented with several services including LogMeIn Hamachi and Weaved among others. I would highly recommend using Weaved because it allows you to meet your goal (SSH to pi behind a router), and the setup is painless. You may even find some other uses that are quite handy.
See the installation details at https://developer.weaved.com/portal/members/betapi.php
Steps to be up and running:
Go to http://www.weaved.com and sign up.
Install weaved on your pi, and follow the prompts for SSH (Instructions at https://developer.weaved.com/portal/members/betapi.php).
Go to "My Devices" at weaved.com and get the new internet accessible proxy address for your pi.
Enjoy!
I don't know whether this is possible but would like to give it a go and see if someone knows something about it.
I work with applications that fix phones and sometime it happens that driver of one application can conflict with another.
I was wondering if is possible to create multiple virtual machines (lightweight) that can host a single software and just drivers related to it so I can isolate the environment from other software.
Let's say I want to create one virtual machine that when I turn on, it will only open a samsung app,it will have it's own drivers, dedicated small space and device connection ability.
I want to do this with multiple software.
I heard of virtual machines like virtual box but thought they are too heavy for running a single app.
How about docker or something similar? can they work for this purpose?
NOTE: I want to run software that run on win 7 only.
Thanks
Docker runs only on Linux; you will need sort of "full virtualization" software to run it on Windows!
I know of several VM software for Windows, but all of them are rather heavy for running a single app. Also, I think you need separate Windows license for each "guest" ("child") Windows installation.
http://www.zdnet.com/article/the-best-and-cheapest-ways-to-get-windows-and-linux-for-virtual-machines/
I writing a mac application and i need to discover other Macs/PCs/iPhones/iPads connected to the same WIFI network.
Bonjour seems to be the most reasonable choice, but it turned out that it has problems on many types of routers (on mine for example, is not working as it blocks Bonjour services).
I just need to find iPs of devices, then i will try to connect to an application-specific port to determine if my process is running there.
What is the best approach to accomplish this task, without violating the App store Sandboxing?
ARP was the first answer which came to my mind. Does your network-setup allows this?
Currently, I am writing an application that utilizes WMI to scan all the computers on our Active Directory network.
I'm interested in testing the program against all flavors of Windows machines in a testing environment.
Is there a way to similuate this environment in VMware or something?
Any ideas?
VMWare works well and can host many virtual computers on a single physical computer. You can also put the virtual computers on your active directory network.
If your goal is to set up a separate large network for testing that has it's own AD server you can look into Amazon EC2 for testing. The advantage here is once you setup your set of servers, you can turn them on and off as needed and only pay for the time actually used ($0.12 per hour).
http://aws.amazon.com/
You can use network simulation: http://en.wikipedia.org/wiki/Network_simulation
and good GPL tool is http://www.nsnam.org/
You have two options.
You probably have it right, with VMWare this is easy, try looking for cloning tools. If you plan on copying and pasting the image, you will get several problems (computer Guids repeated, Network Computer Names repeated, etc)
You can also "mock" the WMI response by wrapping the WMI methods that you want to call and implementing an interface, using Rhino Mock or NMock if you are working in .NET (which I assume you are).
Simplified, I have an application where data is intended to flow over the internet between two servers. Ideally, I'd like to test at what point the software ceases to function. At what lowerbound limit (bandwidth, latency, dropped packets) do things stop working to test the reliability of the software.
What I thought I would do was the following:
Setup up 3 machines (VMware instances)
Install the 2 applications on two of the servers.
Setup up the 3rd server to sit between the two machines by doing some sort of magic with Routing and Remote Access on Windows 2003
Install either Traffic Shaper XP or NetLimiter to limit the bandwidth
Run something like TMnetSim Network Simulator to simulate a bad connection.
Does this sound like a good idea or are there easier/better ways of doing this? I'm not that comfortable on Linux and my team mates are even less so.
WANem does exactly this. We have used it both in a virtual machine on the desktop and on a dedicated old pc and it worked great. It can simulate all sorts of broken connectivity.
FreeBSDs ipfw has provisions to simulate links with a given bandwith, latency or error rate. You could use that FreeBSD machine as your machine "in the middle" in your above setup.
You probably can also run at least one of the endpoints on the same machine if you want to reduce the amount of servers involved.
Someone actually packaged up the settings and whatnot necessary for the FreeBSD solution to this problem and they call it DUMMYNET.
It simulates/enforces queue and bandwidth limitations, delays, packet losses, and multipath effects. It also implements a variant of Weighted Fair Queueing called WF2Q+. It can be used on user's workstations, or on FreeBSD machines acting as routers or bridges.
It can simulate exactly what you want, and its free and will boot onto commodity hardware. They even have a canned install of it that is small enough to put on a floppy disk (!) that you can download at that link.
Maybe it is time to learn a bit about Linux because adding a 50ms delay on every outgoing packet can be done in typing just one line:
tc qdisc add dev eth0 root netem delay 50ms
For more see the Linux Traffic Control HOWTO
We had a similar requirement some ten years ago - I'll see if I can recall how we managed it.
If I remember, we wrote a socket proxy program which was controlled by inetd on a UNIX box. This socket would accept connections from a client and open equivalent sessions through to the server. It would then loop, passing messages in both directions.
The way we achieved WAN characteristics was to introduce random delays (with upper and lower limits) in both the connection establishment and the passing of data once the link was up.
It also had the feature to drop the link occasionally as WAN links were less reliable for us than local traffic.
I recall we had to make it threaded to stop the delays from affecting reverse traffic on the link.
There is a very good (and free) Microsoft solution for that, we use it for quite some time and it works great, it can very easily simulate every thing(packet loss, low bandwidth, disconnection, latency....)
This is the best solution i found for a windows environment
More information and a download link can be found here: MARCO blog post
this product has gone some evolution and it is now integrated into visual studio as part of the automation testing, but i found the use of the standalone(that is quite hard to find, so keep a local copy) to work much better. keep in mind that you need at least two computers(or VMs) since you need to pass through a network adapter in order for the application to work its magic.