# Adding a Subdomain

💡 What is a sub-domain?\
\
A sub-domain is an additional section of a domain that can help organize, specify, or navigate to different websites under a single primary domain.\
\
For example, while navigating from a website `www.example.com` to its store, you may see the domain change to `store.example.com`. This shortens the domain and makes it easier for you and your students to remember. The following method requires a domain to acquire the proper safety features.

![](/files/-MDGhXfUlvwT-4w7w9wS)

Navigate to the "Domain Name Servers," then to "Custom resource records." Enter the desired name (jupyterlab, econlab, etc.). Then enter the IP4 address of your instance.

💡 This will take up to 48 hours to update and begin serving as a functioning URL.

💡 It is still necessary to add `:8000` to the address of your jupyter Hub. It is also feasible to use a reverse proxy, e.g. nginx, to reroute network traffics to your URL to the JupyterHub, see [below](/optional-github-authentication/secure-your-lab.md).


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