Azure Networking or: How I Learned to Stop Worrying and Love Dynamic Addressing

Cloud, Networking
Very few things need statically assigned addresses anymore.  Routers, which includes load balancers and firewalls, and DHCP servers being the top of the list.  Once you move to the cloud, those two are handled for you. If you set a static IP on a device in Azure, it will actually break the networking on the device in strange and interesting ways.  You must configure the networking via the portal, PowerShell, or API.  The "static" IPs you assign from the portal are actually DHCP reservations.  This centralization of IP management makes it incredibly easy to prevent conflicts, track resource utilization, and programatically apply CRUD to the network.  On top of that, it removes the hassle of remembering where to set the IP on the host (/etc/network/interfaces vs /etc/sysconfig/network-scripts vs Set-NetIPAddress). A…
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Of defaults and bad ideas

Since CloudFlare has taken over and, they have started pulling back the curtain on some really ugly default settings.  From router configs with hardcoded ips to really bad documentation not using the RFC5737 IPs, it's apparent that companies great and small are bad users of the internet. To help fight that, please use only your allocated space (either from your RIR or ISP), and for generic documentation use the correct IP space.,, and are all valid IPs, and it's very unlikely that you own them. For documentation, please use the following subnets (RFC5737 and RFC3849): 2001:DB8::/32 In the same vein, for documentation, please use the following domains (RFC2606): For internal networks, please use the following IPs if you absolutely…
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