[Tutorial][Trema] Show Topology

 Trema有一個很不錯的App, 可以利用toplogy與 topology_discovery App, 去產生topology graph…如下:

下列為Network emulation的設定檔內容

# virtual switches

vswitch("switch1") { datapath_id "0x1" }

vswitch("switch2") { datapath_id "0x2" }

vswitch("switch3") { datapath_id "0x3" }

vswitch("switch4") { datapath_id "0x4" }

vswitch("switch4") { datapath_id "0x5" }

# virtual hosts

vhost("host1")

vhost("host2")

vhost("host3")

vhost("host4")

# virtual links

link "switch1", "switch2"

link "switch1", "switch3"

link "switch2", "switch3"

link "switch2", "switch4"

link "switch2", "switch5"

link "switch3", "switch4"
link "switch3", "switch5"

link "switch4", "switch5"

link "switch4", "host1"

link "switch4", "host2"

link "switch5", "host3"

link "switch5", "host4"

[Tutorial] ovsdbmonitor GUI 設定步驟 (setup procedure)

The following steps are the setup procedure for running ovsdbmonitor GUI

(You have to make sure that your "PYTHONPATH" contains the path of openvswitch source path/python. )

   

1. 增加PYTHONPATH到 .bashrc

for example:
PYTHONPATH="${PYTHONPATH}:/home/liudanny/Source/openvswitch-1.2.2/python/"
Export PYTHONPATH

2. 增加一個symbolic link for ovsdb-client
sudo ln -s /usr/local/bin/ovsdb-client /usr/bin/ovsdb-client

3. 執行ovsdbmonitor
“your openswitch path”/ovsdb/ovsdbmonitor/ovsdbmonitor

4. 設定Host Properties:
Host name or IP: your openvswitch host
SSH Password: ***
Connect target: unix:/usr/local/var/run/openvswitch/db.sock
＊     這個connect target 會與 啟動ovsdb-server daemon 的參數有相關 ＊

          sudo ovsdb-server --remote=punix:/usr/local/var/run/openvswitch/db.sock \

                    --remote=db:Open_vSwitch,manager_options \

                    --private-key=db:SSL,private_key \

                    --certificate=db:SSL,certificate \

                    --bootstrap-ca-cert=db:SSL,ca_cert \

                    --pidfile --detach

5.       相關畫面 (可以看到ovs database 內的table content, 每個頁簽都代表一個table)

[Info] Quantum L3 Model and API

The following link is about adding L3 concept and APIs ( routing between Subnets) into OpenStack Quantum.
http://wiki.openstack.org/quantum-l3

The more information is here:
quantum-l3-service-spec-SumitNaiksatam-5.pdf

如何在Python內使用Singleton方法

# There is an example to do with Singleton in Python def singleton(cls): instances = {} def getinstance(): if cls not in instances: instances[cls] = cls() return instances[cls] return getinstance @singleton class MyClass(): def __init__(self): self.data = "AAA" if __name__ == "__main__": obj_a = MyClass() obj_a.data = "AAAA" print obj_a, obj_a.data obj_b = MyClass() print obj_b, obj_b.data

Big Switch: the SDN Coffee Talks

Big Switch Networks Launches SDN Coffee Talks to Further Educate the
Broader IT Community on Software-Defined Networking (SDN)

the SDN Coffee Talks
http://www.bigswitch.com/sdn-coffee-talks/

如何取得Open vSwitch 上的 datapath id

ovs-vsctl -- get bridge br-int datapath_id

[HowTo] Build up GRE Tunneling on Open vSwitch

// Create a bridge
ovs-vsctl add-br br0

// Build up GRE Tunnel on remote host's ip = x.x.x.x
ovs-vsctl add-port br0 gre0 -- set interface gre0 type=gre options:remote_ip=x.x.x.x

In this article, the author explains more info about GRE Tunneling in details.
http://d.hatena.ne.jp/kazuya_ax/20120420/1334928361
The way for him to build GRE Tunneling is as follows:
ovs-vsctl set interface gre0 type=gre options:remote_ip=x.x.x.x options:pmtud=false

Iron Speed Designer

Iron Speed Designer is a .NET web application development tool that can generate your web application straight from your database. You just simply point to an existing database and let the Iron Speed Designer wizards build a sophisticated, database-driven application that's easy to customize and ready to deploy.

If you are a web developer and dedicated in ASP .NET programming, you maybe feel uncomfortable about the information as follows. What I mean is that you probably could not build a .NET web application more better than it if you already have several years work experience with ASP .NET.

Check out these links.

Iron-Speed Designer Web Site:
http://www.ironspeed.com/products/Landing.aspx?c=CP02

Demo Video:
http://www.ironspeed.com/Designer/5.1.0/Videos/5MinuteVideo/5minutevideo.html