What is the significance of the 127.0.0.1 IP address in sign-in logs?

Jean Paul Nkundabose 105 Reputation points
2023-11-30T00:16:46.34+00:00

In my sign-in logs, I noticed the IP address 127.0.0.1. What is the meaning of this IP address, and why is it showing up in my logs?

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  1. Jarvis Sun-MSFT 10,231 Reputation points Microsoft External Staff
    2023-11-30T05:32:48.3333333+00:00

    Hi @Jean Paul Nkundabose ,

    Welcome to our MS Q&A forum!

    The IP address 127.0.0.1 is called the loopback address and is used by a computer to refer to itself. It is also known as localhost. When a server is running on your local PC, it will be accessible at 127.0.0.1. This IP address is reserved for loopback purposes and is not used to communicate with other devices like a real IP address.

    It is possible that you are seeing this IP address in your sign-in logs because your device is trying to connect to a service running on your local machine.


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  1. Anik Pal 0 Reputation points
    2024-11-21T08:45:12.39+00:00

    The IP address 127.0.0.1 is called the loopback address and is used by a computer to refer to itself. It is also known as localhost. When a server is running on your local PC, it will be accessible at 127.0.0.1. This IP address is reserved for loopback purposes and is not used to communicate with other devices like a real IP address.

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  2. Jon Mendes 0 Reputation points
    2024-12-07T08:46:47.9166667+00:00

    It is a loopback address called localhost (127.0.0.1) used for testing particular apps' tasks on the same device you are currently using without connecting to an external device or internet connection.

    Ports, such as 49342, 57573, and 62893, are added to the end of the localhost (e.g., https://100001.pw/127001-49342-57573-and-62893) to route data to specific services or applications locally.

    127.0.0.1 on your login log may be because an app uses it to test or view particular pages on your local device without sending or receiving any data from a third-party.

    Or it may be a malware trying to exploit them for harmful activities. It is always better to scan your website with a anti-virus programme.

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