AWS – Flow Logs and Secondary IP’s on a ENI

Sometimes it may be necessary to add a secondary IP onto an elastic network interface on your EC2 instances. This can be for many reasons such as hosting multiple websites secured with certificates on a single server where each certificate is mapped to an IP, having application or appliances that have rules based on the target IP address and also having a IP address that you could move between different EC2 instances. The following example may help you better understand what you need to watch out for when using flowlogs in this scenario.

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AWS – Overlooked Network Charges

Understanding your network charges within AWS can often be a confusing task; whether you know what your current estate traffic amounts too, or you are building from fresh and don’t really have a full picture of how demand and usage will develop. Even with the best preparation and planning, charges can often seem to be higher or lower and it can take time and effort away from development to understand why. Below I will go through one or two small charges that are often overlooked, but can add up.

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