Verifying DNS#

We have a www.patientping.internal domain name, but it’s only accessible within our VPC.

In other words, this command won’t produce a meaningful IP address locally:

dig www.patientping.internal +short

but if you run that command from the patientping-web-v2 EC2 instance (that’s inside the VPC), you should be able to resolve the domain name!

ssh patientping
dig www.patientping.internal +short
# 10.0.10.50

Example#

Verify that www.patientping.internal resolves from inside patientping-web-v2 over SSH.

  1. SSH into your app server:
ssh patientping
  1. Install dig (if not already installed):
sudo dnf install bind-utils
  1. Run DNS lookup from the server:
dig www.patientping.internal +short
  1. Confirm the command returns 10.0.10.50.
  2. Exit the server:
exit
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