Networking in Azure
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In Azure, we can create virtual networks with subnets using a service called as Azure VNET.
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To understand networking in Azure we need to know about Regions in Azure
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When ever we need to create any resource in Azure, it has to be part of a group (Resource Group).
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Resource Group has resources which can be from same or different regions
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In Azure when we create a Network, the Network is created at a Region level
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Lets create a first vnet
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Exercise: Create a virtual network with 4 subnets, which are capable of 500 devices each.
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In any network, We cannot use 2 IP addresses
- All 0 will be Network Id
- All 1 (255) will be broadcast id
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In the case of Azure we cannot 5 IP Addresses
- All 0 will be Network Id (x.x.x.0)
- ALL 1 will be broadcast id (x.x.x.255)
- x.x.x.1 Reserved by Azure for the default gateway
- x.x.x.2 and x.x.x.3 Reserved by Azure to Map the Azure DNS IPs to VNET Space
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In Azure the Smallest subnet possible is /29
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Azure Network will have default routing which enables all the communication within vnet.
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When we want to create vm’s, Every VM has to be part of some subnet. Networking is connected to VM using NIC (Network interface card), This is virtual NIC and this receives the private ip address from the configured address space (cidr range)
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While creating vm, we can choose a public ip address for this NIC so that we can access the VM from internet.
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Now lets create the following network in Azure
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Now lets try to create a ubuntu vm with public ip in subnet1
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Lets look at network interface
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Lets ssh into this machine
ssh <username>@<publicip>
- Now lets try to create one more ubuntu vm in subnet2 without publicip
- We cannot directly login into vm created in subnet2, but we can login into vm1 and from there login into vm2
- Observations made:
- VM with public ip is able to access internet
- VM without public ip is not able to access internet.
