Move admin application settings to own path

[ci skip]

1 files changed, 22 insertions, 0 deletions

diff --git a/doc/user/admin_area/settings/sign_up_restrictions.md b/doc/user/admin_area/settings/sign_up_restrictions.md
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+# Sign-up restrictions
+
+## Blacklist email domains
+
+> [Introduced][ce-5259] in GitLab 8.10.
+
+With this feature enabled, you can block email addresses of a specific domain
+from creating an account on your GitLab server. This is particularly useful to
+prevent spam. Disposable email addresses are usually used by malicious users to
+create dummy accounts and spam issues.
+
+This feature can be activated via the **Application Settings** in the Admin area,
+and you have the option of entering the list manually, or uploading a file with
+the list.
+
+The blacklist accepts wildcards, so you can use `*.test.com` to block every
+`test.com` subdomain, or `*.io` to block all domains ending in `.io`. Domains
+should be separated by a whitespace, semicolon, comma, or a new line.
+
+![Domain Blacklist](img/domain_blacklist.png)
+
+[ce-5259]: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/5259