How do I add, delete or modify a flow using opendaylight? - opendaylight

I have set up an SDN using Open vSwitch and OpenDaylight.
I have two machines with Ubuntu and I am using KVM to simulate two devices (for now). I have two other devices in the network. The OpenDaylight Dlux network topology shows an openflow switch and five hosts - the two virtual devices, two real devices and the one machine; the other machine is the one that has ovs and odl and the KVMs.
Now I want to play with flow control... From one of the virtual devices, I can ping the other host/machine - traffic flows from the host through the openflow switch. I am working on setting up a samba server so that I will be able to wget a file from that machine. BUT ultimately, I want to change the flow, so that when I try to download the file, it will instead go from the host through one of the real devices.
I am having trouble locating relevant documentation about how to add/modify/delete a flow using opendaylight (that I can understand). Maybe that last part is the actual problem, but thought I would ask here for some guidance!

if you want to play with flow you have to use opendaylight openflow plugin here the user guide link
http://docs.opendaylight.org/en/stable-oxygen/user-guide/openflow-plugin-project-user-guide.html
you can install postman and send the request to the openflow plugin,,, you can change flow on each port , QOS, flow timeout, ..etc.

Related

how we can use web socket from multiple IP addresses in JMeter

I need to connect and send request for websocket from different IPs in jmeter to my singalR server. How can I do it. I know in case of HTTP request we can do that in jmeter by creating multiple IP addresses alias on the machine as mentioned in the link https://www.blazemeter.com/blog/how-to-send-jmeter-requests-from-different-ips.
How this process will work for websockets.?
Thanks.
It will not as the possibility to set outgoing IP address needs to be present in the WebSocket plugin you're using.
Currently available solution is to allocate as many machines as IP addresses you need and run JMeter in distributed mode. If a single machine is powerful enough you can kick off several JMeter slave processes there, keep in mind that:
you need to have these IP addresses (or aliases) defined at OS level
you need to bind the slaves to different ports
If you can do Java programming you can add it yourself, the project lives at https://github.com/ptrd/jmeter-websocket-samplers, somewhere here
If you cannot - you can ask the plugin developer to add this feature either via GitHub or try reaching out to him via JMeter Plugins Support Forum

OSX - Conditionally block outgoing connection to web service, based on wifi network / LAN connection

I've got a cloud backup programme that I'd like to only run when connected to one particular wifi network / LAN. As the other networks I connect to regularly dont have another bandwidth to backup the computer over the internet.
I've been thinking of ways to Block / Allow outgoing connection to select services / sites based on what LAN / wireless network your connected to, and have looked at some GUI apps such as Little Snitch and Tripmode, but these both work on the principal of blocking all outgoing connections and having you manually approve each new connection, they also let you do this on a per network basis.
Really I just want to block 1 outgoing connection, which got me thinking of ways to do this, could i add the site / service i want to block to my DNS block list, but only have it triggered conditionally when connected to a pre defined wifi network / LAN (I can't do this on an external IP basis as I have a dynamic IP at the site where I want to backup from).
I'm running OSX 10.10.5
You can use something like Control plane to run script on location change.
The script, for example, can add a line to /etc/hosts with the backup endpoint address pointing to localhost.

Omnet++ : Ad Hoc Network

I am new to Omnet++. Although I have tried some basic examples such as Tic-Toc and Source-Sink, I cannot figure out how to implement more sophisticated networks.
Problem : I want to implement Ad Hoc Network. I have tried examples given in INET but they only ping each other and reply. They do not exchange actual messages. I want my network to have actual information in form of messages and then communicate these messages through ad hoc network to different nodes. Please help!!
You should be fine with the examples in inet/examples/adhoc/ieee80211 and inet/examples/manetrouting.
As for 'real' traffic. You are free to configure any traffic type you wish in the hosts. Pinging is just an example. Take a look at inet/examples/inet/udpburst to see how burting UDP traffic is configured.
Traffic generated by the applications inside a hosts are totally independent of how they are communicating (just as in real life). I can ping and run a browser equally with both a wireless and a wired connection.
i.e. you CAN combine the different examples.

Redirect Traffic from NIC to Another NIC On Separate Networks While Using Remoting

The project I'm working on is to handle data capture from scan guns (Pocket PC 2003) and process this data on a host (Win XP) then into our inventory database on a separate server (Win 2000). This is all driven by the Remoting framework provided by MS and As Good As It Gets (http://gotcf.net). The application is complete enough for a general proof of concept with both the client and server working properly while in the emulator.
All is well until I began to test using actual scan guns. Due to security concerns, the scanners are on a separate network (for clarification the 10 network) than the server (the 15 network). My development machine has dual NIC connected to both networks and can communicate with both independently. However, I am having issues with my application receiving information from the 10 network using .Net Remoting, and then sending out information to the server on the 15 network via a third party app (Combination of ODBC, Btrieve, and OLE).
Is there anyway to process information from one network then update the server on another?
Any suggestions will be greatly appreciated!
Note: I'm not very familiar with networking, thus I may be calling it the wrong name but the gun IP's start with 10...* and the server IP's start with 15...*
So long as the computer's routing table is properly configured, you shouldn't have to worry about this from your application. So long as you're using the proper IP addresses, the networking stack should take care of delivering things to the right place.
You might want to check the output of "route print" (at least I think that was available on WinXp -- if not, someone else will likely post the correct command for XP soon). In any way, you should see what network destinations are configured for which interfaces. You'll need to make sure that the server's IP on the 15 network will properly route via the interface you want (ie. the lowest-cost matching destination/netmask lists your 15 interface).
The issue seems to stem from both the NIC cards not set up properly and a so far unresolved issue with the frameworks I've chosen.
To solve the NIC problem, the easiest solution I'd found had me clear the default gateway on the 10 network.
The other issue deals with recreating the remoting objects after they've been destroyed. I currently have to warm boot the scanner in order to re-connect to the host. In order to correct this issue I'm going to contact As Good As It Gets to see what their input is. Damn firewall

How do you diagnose network issues on Windows?

I often run into problems where I can't get something to connect to something else. I usually forget to check something obvious. Can you help with:
A tip/technique for diagnosing a connection issue
The name of a tool or application that can help (and the situation in which it's useful)
I know the question is a little non-specific, but hopefully the answers can form a useful starting point for anybody who's stuck trying to get computers/programs talking to each other.
Please can you give one answer per answer so the best ones can be voted up.
Simple checks to run when debugging network problems:
Has each machine got an IP address, Go to command prompt and run ipconfig. Key things to check here are the interfaces and ensuring the appropriate ones have IP addresses.
Check both machines IP addresses are in the same range and subnet if you are running it on an internal or Virtual network.
Try pinging each machine from the other to see if they can communicate with each other. Note that some firewalls will block ping requests.
If Pinging fails then check to see if firewalls are active. If the communication is within a 'safe' internal network then try disabling the firewalls and re-pinging.
If the connections are over a wireless network then check signal strength.
If pinging fails and you are connecting through several networks then try running a tracert to see at which will may show you where on the network the connection is failing.
If you are able to ping but not connect then check firewall settings and network connection settings. Windows 2000+ has the capability of setting port an ip access on a connection properties.
Try drawing a network diagram of the connections to help in visualising the problem.
If you are connecting through routers, firewalls and loadbalancers then check that all devices are not tied to any specific ip addresses and that the IP address redirection (if in place) is correct. Also check any NAT logs to see if connections are being received and properly re-directed.
Wireshark
Latest versions of ProcMon
netstat
Wireshark www.wireshark.org
Wireshark is a network protocol analyzer for Unix and Windows.
Features:
Deep inspection of hundreds of protocols, with more being added all the time
Live capture and offline analysis
Standard three-pane packet browser
Multi-platform: Runs on Windows, Linux, OS X, Solaris, FreeBSD, NetBSD, and many others
Captured network data can be browsed via a GUI, or via the TTY-mode TShark utility
The most powerful display filters in the industry
Rich VoIP analysis
Read/write many different capture file formats: tcpdump (libpcap), Catapult DCT2000, Cisco Secure IDS iplog, Microsoft Network Monitor, Network General Sniffer® (compressed and uncompressed), Sniffer® Pro, and NetXray®, Network Instruments Observer, Novell LANalyzer, RADCOM WAN/LAN Analyzer, Shomiti/Finisar Surveyor, Tektronix K12xx, Visual Networks Visual UpTime, WildPackets EtherPeek/TokenPeek/AiroPeek, and many others
Capture files compressed with gzip can be decompressed on the fly
Live data can be read from Ethernet, IEEE 802.11, PPP/HDLC, ATM, Bluetooth, USB, Token Ring, Frame Relay, FDDI, and others (depending on your platfrom)
Decryption support for many protocols, including IPsec, ISAKMP, Kerberos, SNMPv3, SSL/TLS, WEP, and WPA/WPA2
Coloring rules can be applied to the packet list for quick, intuitive analysis
Output can be exported to XML, PostScript®, CSV, or plain text.
work the OSI model from the bottom up
Physical (Do you have a network adapter/connection)
Link layer (arp, ethernet port blocked by network team (I've seen this where locked down environments see two MAC addresses coming from one workstation port and shut down the port)
Network layer (ipconfig, tracert, ping,)
Do you have a network address (DHCP, fixed)
Are you on a proper subnet/have routing between subnets
Is something in the middle blocking you
firewalls, routing tables
When in doubt, check to see if the windows firewall is messing with your communications. 8 times out of 10, it's at fault.
Using tracert is a good start to see how far along the chain you are getting.
For virtual machines it's usally a good idea to make sure you have the loopback adapter set correctly in the Host os.
Most frequently used tool is the ping. It can be used both to test your connection and the availability of a target
Second tool is the tracert if you want to see where the packets get lost.
For more advanced debugging I use the following tools: nmap, wireshark, etc.
Windows has a netstat utility which is pretty similar to the Unix netstat and can do a number of different things that might help you solve network issues.
Random example:
netstat -r displays routing information
netstat /? for usage information
Since you said you're using 2 virtual machines I would hazard a guess that both machines are setup in a NAT configuration (rather than a unique network device) -- In the NAT configuration, neither machine would (typically) be able to ping the other.
If you're familiar with the command line, you can try the "netstat" command.
You can also try "arp -a" to list all the IP/MAC addresses known to your PC.
The "tracert [ip address]" command will show you how many gateways/routers your packets jump through on their way to their destination. (This is probably not helpful if both machines are on the same network, though.)
And don't forget to check your Windows firewall settings.
Otherwise, if you want to get down and dirty, you can try the packet sniffer known as Wireshark: http://www.wireshark.org/ (aka. Ethereal)
Pull the network cable out
If you can get some communications to a device (eg a ping), but can't get your program to talk to a service on the computer. Then, try pulling the network cable out and see if the ping stops. This will verify you're communicating with the computer you really think you are.
On windows i user PortQueryUI : http://www.microsoft.com/en-us/download/details.aspx?id=24009
DNS activity: Portable DNS Cache and Firewall;
General network activity: Wireshark, Network Monitor;
Windows utilities: ping, netstat, nslookup.
You need to be use the process of elimination, for example if you can ping the ip address but not the hostname then there's DNS issues. If you can ping the system but not connect to a share etc.
DNS out of sync
If you're using a virtual machine and you perform a roll-back on it, then it could become out of sync with the DNS (Domain name server). Try to remove and re-add the machine to the domain, or if you've got access to the DNS machine, then get it to flush its cache.

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