Networking Facts in Azure – Allowed vs Not-Allowed IPv4 address space in Azure
Networking Facts in Azure – Allowed vs Not-Allowed IPv4 address space in Azure
Recommended Address Space:
RFC 1918
10.0.0.0 – 10.255.255.255 (10/8 prefix)
172.16.0.0 – 172.31.255.255 (172.16/12 prefix)
192.168.0.0 – 192.168.255.255 (192.168/16 prefix)
Not Allowed Address space
224.0.0.0/4 (Multicast)
255.255.255.255/32 (Broadcast)
127.0.0.0/8 (Loopback)
169.254.0.0/16 (Link-local)
168.63.129.16/32 (Internal DNS)
Reserved IPs in a subnet:
x.x.x.0: Network address
x.x.x.1: Reserved by Azure for the default gateway
x.x.x.2, x.x.x.3: Reserved by Azure to map the Azure DNS IPs to the VNet space
x.x.x.255: Network broadcast address
Smallest and largest IP address space:
Smallest /29
Largest /8
Some interesting facts:
TCP, UDP, TCP/IP
You cannot ping default router in Azure
You cannot use traceroute/tracert to diagnose network issues
You can modify the size of the subnets if no resources are deployed
You can also modify address space in a VNET afterwords
VNET cannot span multiple regions
Where to use IP?
VM / NIC
Load Balancers
Azure Firewall
VPN GW
Note by Default, all VMs created will have connectivity to the internet by default!
ipv4
