Some web servers control access to their sites by requiring that
forward and reverse entries for the client computer are registered in the domain
name service (DNS). A common further requirement is that the client computer be
registered in an Argonne domain, thereby having a name ending with anl.gov.
The tests on this page are designed to help us diagnose web site access problems in a
Your IP number is 220.127.116.11
Your host DNS name is ec2-54-161-40-41.compute-1.amazonaws.com
Frequently Encountered Problems
- Computers with no dns entries cannot access either link 2a or 2b.
- Computers with incorrect dns entries (forward or reverse) cannot access
either link 2a or 2b.
- Computers with domain names registered in dns that are different from the names configured in the computers
cannot access either link 2a or 2b.
- Computers with extra dns entries that are not active (would not respond to
ping) cannot access either link 2a or 2b.
Additional Test Rules
- All computers will reach a web page with either the 1a or 1b link regardless
of the dns configuration.
- All computers will reach a web page with either the 2a or 2b link but only if dns is properly
1. Test your computer's IP number by choosing the a or b link:
Computers with an IP number in the Argonne IP space
Computers with an IP number NOT in the Argonne IP space
If you reach a web page with the a link, your computer is in the
Argonne IP space. If you reach an error page, your computer is not in the
Argonne IP space. Your result for link b will be the opposite of
that for link a.
2. Test your DNS entry by choosing the a or b link:
Computers with domain names ending in anl.gov
with domain names NOT ending in anl.gov