Archive for the tag 'DNS'

Understanding DNS, propagation and migration

We recently had a customer that was migrating from one DNS provider to another due to large outages from their existing supplier ie. a failure to keep their DNS services working correctly. They went ahead and migrated by changing their A Record and MX records for their domain/ sub-domains and only contacted us when they [...]

Using Amazon EC2 public IP address inside EC2 network

Each AMI instance on EC2 is assigned two IP addresses and corresponding DNS names. A public IP address that is accessable over the internet and an internal IP address only accessable inside internal EC2 regional network. You don’t have any control over the internal IP address and it is assigned randomly when you start the [...]