Windows Azure Virtual Machine (18)

Azure Virtual Machine Internal IP and external IP

According to the above, we created 2 separate virtual Machine:

The first machine named Leizhangvmone

The second machine is named Leizhangvmtwo

They share the same cloudservice name:http://leizhangvm.cloudapp.net

When we look at 2 VM properties through the Azure Management portal, we find the following:

By the red area above, we find that

-The internal IP address of the first VM and the second VM is different

-public Virtual IP (VIP) address is the same

Analysis: Internal IP address is the VM in the Azure Data center of the Internal network addresses, it is obtained from DHCP, so every time the azure VM shut down after a period of boot, Internal IP changed. (If you want to fix internal IP address, you'll need to use Azure Virtual network, which I'll tell you later).

To verify the author's view, we can view the network properties of one of the VMS via Remote Desktop Connection.

Leizhangvmone the IPV4 address of this machine is 100.80.76.15. Consistent with the internal IP address of the first picture.

Also, if we set the shared folder Sharefolder in the first virtual machine Vmone and set permissions to everyone. We can access the shared folder of the first virtual machine via a second virtual machine vmtwo Remote Desktop Connection.

Please note: Since Vmone and Vmtwo share the same cloud Service and are in the same avaliability Set, the two machines can access each other. Other Azure VMs created by the same user will not be able to network access to previous Vmone and Vmtwo if the same avaliability set is not set.

Second question: What is public Virtual IP (VIP) address? This address is actually the public IP address of the Azure VM.

See more highlights of this column: http://www.bianceng.cnhttp://www.bianceng.cn/Servers/cloud-computing/

But the real IP address does not belong to an azure VM, but is in the azure Load balance. The main function of the VIP is load-balancing (load Balance), and after the VM is deleted, the VIP will be reclaimed by the system. So this IP is virtual.

When other clients on the Internet (such as the author's notebook computer). When accessing Azure resources via VIP, Load balance will pass the request through endpoint and automatically route to internal IP address, which may send the request to Vmone or vmtwo. When an exception occurs in a machine in Vmone or vmtwo, load balance sends the request to a normal VM to ensure high availability.

To verify the author's claim, we use the local computer to open cmd, and then run the nslookup command. To view the IP address for this DNS http://leizhangvm.cloudapp.net. The following figure:

You can see that the IP address (137.116.164.27) for this DNS address is our public Virtual IP (VIP) addresses on the Azure portal (http://leizhangvm.cloudapp.net).

See here, some netizens will certainly ask: Why should Azure VM use internal IP and public Virtual IP?

When some scenarios require multiple VMs to communicate with each other, the author recommends using internal IP. Because the internal IP security is reliable, the user does not need to consider the security authentication, the SSL and so on. And after using the virtual network (which I will introduce in subsequent chapters), you can connect the corporate intranet to the Azure network so that the company intranet can access the VM on the public cloud via Azure Internal IP. Users can take advantage of the flexible computing generated by cloud computing to reduce the cost of IT investment.

Public virtual IP (VIP) Benefits: The author believes that the public virtual IP the biggest advantage is that you can do load balancing (load Balance).

About IP Recycling:

When the user deletes both Vmone and Vmtwo, the Internal IP address and the public Virtual IP address will also be reclaimed by Windows Azure. If other users create virtual machines, they may use the internal IP and VIP that are recycled.

What if the user uses shut down to shut down the azure VM? I will introduce it in the next chapter.