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+AD LDAP auth
+===
+
+
+To setup your CodiMD instance with Active Directory you need the following configs:
+
+```
+CMD_LDAP_URL=ldap://internal.example.com
+CMD_LDAP_BINDDN=cn=binduser,cn=Users,dc=internal,dc=example,dc=com
+CMD_LDAP_BINDCREDENTIALS=<super secret password>
+CMD_LDAP_SEARCHBASE=dc=internal,dc=example,dc=com
+CMD_LDAP_SEARCHFILTER=(&(objectcategory=person)(objectclass=user)(|(sAMAccountName={{username}})(mail={{username}})))
+CMD_LDAP_USERIDFIELD=sAMAccountName
+CMD_LDAP_PROVIDERNAME=Example Inc AD
+```
+
+
+`CMD_LDAP_BINDDN` is either the `distinguishedName` or the `userPrincipalName`. *This can cause "username/password is invalid" when either this value or the password from `CMD_LDAP_BINDCREDENTIALS` are incorrect.*
+
+`CMD_LDAP_SEARCHFILTER` matches on all users and uses either the email address or the `sAMAccountName` (usually the login name you also use to login to Windows).
+
+*Only using `sAMAccountName` looks like this:* `(&(objectcategory=person)(objectclass=user)(sAMAccountName={{username}}))`
+
+`CMD_LDAP_USERIDFIELD` says we want to use `sAMAccountName` as unique identifier for the account itself.
+
+`CMD_LDAP_PROVIDERNAME` just the name written above the username and password field on the login page.
+
+
+Same in json:
+
+```json
+"ldap": {
+    "url": "ldap://internal.example.com",
+    "bindDn": "cn=binduser,cn=Users,dc=internal,dc=example,dc=com",
+    "bindCredentials": "<super secret password>",
+    "searchBase": "dc=internal,dc=example,dc=com",
+    "searchFilter": "(&(objectcategory=person)(objectclass=user)(|(sAMAccountName={{username}})(mail={{username}})))",
+    "useridField": "sAMAccountName",
+},
+```
+
+More details and example: https://www.npmjs.com/package/passport-ldapauth