1.1.1.1 resolves outlook.office365.com to IP addresses in Cape Town

Website, Application, Performance DNS & Network
1

Hi,

We have customers located in Belgium using the Cloudflare DNS server 1.1.1.1.
We discovered that 1.1.1.1 sometimes resolves outlook.office365.com to IP addresses in Cape Town instead of nearby IP addresses in Amsterdam, London or Paris. The DNS responses get cached into the local DNS servers of our customers, causing huge delays in Outlook
This issue occurred since Monday June 3 2024.
Can this be checked by the Cloudflare engineers why this is happening.
Below is an output of nslookup :

> outlook.office365.com.
Server:  one.one.one.one
Address:  1.1.1.1

Non-authoritative answer:
Name:    cpt-efz.ms-acdc.office.com
Addresses:  2603:1006:1:21::2
          2603:1006:1:a::2
          2603:1006:1:819::2
          2603:1006:1:27::2
          52.98.21.34 -> Cape Town (SA)
          52.98.20.226 -> Cape Town (SA)
          52.98.16.226 -> Cape Town (SA)
          52.98.21.50 -> Cape Town (SA)
Aliases:  outlook.office365.com
          ooc-g2.tm-4.office.com
          outlook.ms-acdc.office.com
1 Like
2

Welcome to the Cloudflare Community. :logodrop:

You may want to read this recent topic that has had a response from Cloudflare. It may be helpful.

3

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