Authentication faq (#144)

* Authentication faq

* add CLA

* update

docs/manual-EN/3.build-develop-and-administration/4.account-management-statements/authentication.md

@@ -6,19 +6,23 @@ Authentication is the process of mapping this session to a specific user. Once t
 
 **Nebula Graph** supports two authentication methods, explained in detail below - local and LDAP.
 
-## Local Authentication
+## Local authentication
 
 The local database stores usernames, encrypted passwords, local user settings and remote LDAP user settings. When a user tries to access the database, they will be met with a security challenge.
 
-You need to enable the local authentication by setting the `--enable_authorize` property in the `nebula-graphd.conf` file (the directory is `/usr/local/nebula/etc/` by default) to `true`.
+To enable the local authentication, follow these steps:
 
-## LDAP Authentication
+1. Set the `--enable_authorize` property in the `nebula-graphd.conf` configuration file (the directory is `/usr/local/nebula/etc/` by default) to `true`.
+2. Save your modification in step one and close the `nebula-graphd.conf` configuration file.
+3. Restart the Nebula Graph services.
+
+## LDAP authentication
 
 Lightweight Directory Access Protocol (LDAP) is a lightweight client-server protocol for accessing directory services. Users stored inside LDAP take precedence over the local database users. For example, if both providers have a user called “Amber”, the settings and roles for this user will be sourced from LDAP.
 
 Unlike local authentication, besides enabling the `--enable_authorize` parameter, LDAP needs to be configured in the `nebula-graphd.conf` file (the directory is `/usr/local/nebula/etc/` by default). Refer to the [Integrating LDAP Document](LDAP.md) for details.
 
-### LDAP Parameters
+### LDAP parameters
 
 | Parameter            | Type   | Default Value                                                             | Description                                                                                            |
 | -------------------- | ------ | ------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------ |
@@ -33,6 +37,12 @@ Unlike local authentication, besides enabling the `--enable_authorize` parameter
 | ldap_searchattribute | string | ""                                                                        | An array of the required attributes.                                                                   |
 | ldap_searchfilter    | string | ""                                                                        | Specifies a search filter by defining what to search for. It is more flexible than the searchattribut. |
 
+## FAQ
+
+### Error information: Authentication fails, Invalid data length
+
+Authentication fails because you had not enable the authentication. Follow the preceding steps to enable the authentication.
+
 <!-- restrict the attributes and values returned by the server to just those required. -->
 <!-- When LDAP is turned on, the following security settings can be used to configure it:
 
@@ -62,4 +72,4 @@ ObjectClass attribute specifies the object classes of an entry, which (among oth
 | dn       | Distinguished Name | The unique identifier for an entry in the tree, similar to the absolute path in the Linux file system. For example “uid= tom,ou=market,dc=example,dc=com” is unique in a tree. |
 | rdn      | Relative dn        | Each entry has a unique name relative to its parent called RDN. For example “uid=tom” or “cn= Thomas Johnson”.                                                                 |
 | c        | Country            | c is an LDAP attribute that means country name. For example "CN" and "US".                                                                                                     |
-| o        | Organization       | Organization name. For example “Example, Inc.”                                                                                                                                 | --> |
+| o        | Organization       | Organization name. For example “Example, Inc.”                                                                                                                                 |  | -->

docs/manual-EN/3.build-develop-and-administration/7.monitor/5.rocksdb-statistics.md

@@ -1,8 +1,8 @@
-# RocksDB Statistics
+# RocksDB statistics
 
 **Nebula Graph** uses RocksDB as its underlying storage. The purpose of this document is to teach you how to collect and display the RocksDB statistics for **Nebula Graph**.
 
-## Enabling the RocksDB Statistics
+## Enabling the RocksDB statistics
 
 The RocksDB Statistics function is disabled by default. If you want to enable the RocksDB statistics function, you need to:
 
@@ -11,7 +11,7 @@ The RocksDB Statistics function is disabled by default. If you want to enable th
 
 When the function is enabled, the statistics is dumped to the log file of each DB service regularly.
 
-## Getting the RocksDB Statistics
+## Getting the RocksDB statistics
 
 You can use the built-in web interface in the storage service to get the statistics. There are three methods to get the RocksDB statistics by using the web service:
 

docs/manual-EN/4.contributions/how-to-contribute.md

@@ -1,5 +1,13 @@
 # How to Contribute
 
+## Before you get started
+
+### Sign the CLA
+
+Click the **Sign in with Github to agree** button to sign the CLA.
+
+What is [CLA](https://www.apache.org/licenses/contributor-agreements.html)?
+
 ## Step 1: Fork in the Cloud
 
 1. Visit https://github.com/vesoft-inc/nebula