diff --git a/input/forward.md b/input/forward.md
index 0dc89d6b..0fa53ab1 100644
--- a/input/forward.md
+++ b/input/forward.md
@@ -86,6 +86,8 @@ With this configuration, the emitted tag is `prod.INCOMING_TAG`, e.g. `prod.app.
 
 The timeout used to set the linger option.
 
+This parameter is deprecated since v1.14.6. Use `<transport>` directive instead.
+
 ### `resolve_hostname`
 
 | type | default | version |
@@ -156,7 +158,29 @@ This iterates incoming events. So, if you send larger chunks to `in_forward`, it
 
 ### `<transport>` Section
 
-This section is for using SSL transport:
+This section is for setting TLS transport or some general transport configurations.
+
+#### General configuration
+
+##### `linger_timeout`
+
+| type | default | available transport type | version |
+| :--- | :--- | :--- | :--- |
+| integer | 0 | tcp, tls | 1.14.6 |
+
+The timeout \(seconds\) to set `SO_LINGER`.
+
+The default value `0` is to send RST rather than FIN to avoid lots of connections sitting in TIME_WAIT on closing.
+
+You can set positive value to send FIN on closing.
+
+```text
+<transport tcp>
+  linger_timeout 1
+</transport>
+```
+
+#### TLS configuration
 
 ```text
 <transport tls>
diff --git a/input/http.md b/input/http.md
index 383f83b6..3e6f9386 100644
--- a/input/http.md
+++ b/input/http.md
@@ -166,7 +166,29 @@ Respond status code with 204. This option will be deprecated at v2 because fluen
 | :--- | :--- | :--- | :--- |
 | enum | tcp | tcp, tls | 1.5.0 |
 
-This section is for using TLS transport.
+This section is for setting TLS transport or some general transport configurations.
+
+#### General configuration
+
+##### `linger_timeout`
+
+| type | default | available transport type | version |
+| :--- | :--- | :--- | :--- |
+| integer | 0 | tcp, tls | 1.14.6 |
+
+The timeout \(seconds\) to set `SO_LINGER`.
+
+The default value `0` is to send RST rather than FIN to avoid lots of connections sitting in TIME_WAIT on closing.
+
+You can set positive value to send FIN on closing.
+
+```text
+<transport tcp>
+  linger_timeout 1
+</transport>
+```
+
+#### TLS configuration
 
 ```text
 <transport tls>
diff --git a/input/tcp.md b/input/tcp.md
index 46cd9ced..e2a13e3e 100644
--- a/input/tcp.md
+++ b/input/tcp.md
@@ -137,9 +137,35 @@ You will get something like below:
 
 | type | default | available values | version |
 | :--- | :--- | :--- | :--- |
-| enum | udp | tls | 0.14.12 |
+| enum | tcp | tcp, tls | 0.14.12 |
 
-This section is for using TLS transport.
+This section is for setting TLS transport or some general transport configurations.
+
+#### General configuration
+
+##### `linger_timeout`
+
+| type | default | available transport type | version |
+| :--- | :--- | :--- | :--- |
+| integer | 0 | tcp, tls | 1.14.6 |
+
+The timeout \(seconds\) to set `SO_LINGER`.
+
+The default value `0` is to send RST rather than FIN to avoid lots of connections sitting in TIME_WAIT on closing.
+
+You can set positive value to send FIN on closing.
+
+```text
+<source>
+  @type tcp
+  # other plugin parameters
+  <transport tcp>
+    linger_timeout 1
+  </transport>
+</source>
+```
+
+#### TLS configuration
 
 ```text
 <transport tls>
@@ -148,6 +174,8 @@ This section is for using TLS transport.
 </transport>
 ```
 
+See [**How to Enable TLS Encryption**](#how-to-enable-tls-encryption) section for how to use and see [Configuration Example](../plugin-helper-overview/api-plugin-helper-server.md#configuration-example) for all supported parameters.
+
 Without `<transport tls>`, `in_tcp` uses raw TCP.
 
 ### `<security>` Section
diff --git a/plugin-helper-overview/api-plugin-helper-server.md b/plugin-helper-overview/api-plugin-helper-server.md
index 6ccd9125..880cacac 100644
--- a/plugin-helper-overview/api-plugin-helper-server.md
+++ b/plugin-helper-overview/api-plugin-helper-server.md
@@ -160,7 +160,31 @@ end
 
 ## Configuration example
 
-Here is some TLS configuration examples:
+### General configuration
+
+#### `linger_timeout`
+
+| type | default | available transport type | version |
+| :--- | :--- | :--- | :--- |
+| integer | 0 | tcp, tls | 1.14.6 |
+
+The timeout \(seconds\) to set `SO_LINGER`.
+
+The default value `0` is to send RST rather than FIN to avoid lots of connections sitting in TIME_WAIT on closing.
+
+You can set positive value to send FIN on closing.
+
+```text
+<source>
+  @type tcp
+  # other plugin parameters
+  <transport tcp>
+    linger_timeout 1
+  </transport>
+</source>
+```
+
+### TLS configuration: Basic examples
 
 1. Use existing certs \(signed by public CA or self signed CA\)
 2. Use certs automatically generated by Fluentd
@@ -218,7 +242,7 @@ If `ca_cert_path` and `ca_private_key_path` are specified, certs generation is e
 </source>
 ```
 
-### `cert_verifier` example
+### TLS configuration: `cert_verifier` example
 
 `cert_verifier` is supported since v1.10.0.