Hi,

Recently we identified a web server misconfiguration on our v3 anchors, such that those anchors would not respond as expected to requests with their IP literal in the URL. Requests to their FQDN worked as expected.

• http://nl-ams-as3333-3.anchors.atlas.ripe.net:80/ would respond as expected, but
  
• http://[2001:67c:2e8:3::c100:a4]:80/ would respond with a 404 status code.

The configuration was fixed and deployed by around 0900UTC on 16 January, 2018. V3 anchors now respond correctly to requests issued with their IP literal in the URL.

This affected HTTP measurements to v3 anchors as follows:

• Before the fix was deployed, HTTP measurements to a v3 anchor with 'Resolve on probe' set to false will have used the IP literal, and thus logged a 404 status code.
• HTTP measurements as above that were running when the fix was deployed will have started returning correct results part-way through their run. If the measurement is ongoing, no other action needs to be taken.
• HTTP measurements with 'Resolve on probe' set to true always operated as expected.