diff --git a/README-zh.md b/README-zh.md
index 83d1bd6..7c993b0 100644
--- a/README-zh.md
+++ b/README-zh.md
@@ -82,9 +82,9 @@ wget https://git.io/vpnsetup-amzn -O vpn.sh && sudo sh vpn.sh && sudo bash /opt/
## 系统要求
一个新创建的 Amazon EC2 实例，使用这些映像之一：
-- Ubuntu 20.04 (Focal), 18.04 (Bionic) 或者 16.04 (Xenial)
+- Ubuntu 20.04 (Focal) 或者 18.04 (Bionic)
- Debian 10 (Buster)[\*](#debian-10-note) 或者 9 (Stretch)
-- CentOS 8 或者 7
+- CentOS 8[\*\*](#centos-8-note) 或者 7
- Red Hat Enterprise Linux (RHEL) 8 或者 7
- Amazon Linux 2
@@ -104,6 +104,8 @@ wget https://git.io/vpnsetup-amzn -O vpn.sh && sudo sh vpn.sh && sudo bash /opt/
\* Debian 10 用户需要使用标准的 Linux 内核（而不是 "cloud" 版本）。更多信息请看 这里。如果你在 EC2 上使用 Debian 10，你必须首先换用标准的 Linux 内核，然后运行 VPN 安装脚本。
+
+\*\* CentOS Linux 8 的支持将于2021年12月31日结束。更多信息请看 这里。
:warning: **不要** 在你的 PC 或者 Mac 上运行这些脚本！它们只能用在服务器上！
diff --git a/README.md b/README.md
index c2a617b..dde327d 100644
--- a/README.md
+++ b/README.md
@@ -82,9 +82,9 @@ For other installation options and how to set up VPN clients, read the sections
## Requirements
A newly created Amazon EC2 instance, from one of these images:
-- Ubuntu 20.04 (Focal), 18.04 (Bionic) or 16.04 (Xenial)
+- Ubuntu 20.04 (Focal) or 18.04 (Bionic)
- Debian 10 (Buster)[\*](#debian-10-note) or 9 (Stretch)
-- CentOS 8 or 7
+- CentOS 8[\*\*](#centos-8-note) or 7
- Red Hat Enterprise Linux (RHEL) 8 or 7
- Amazon Linux 2
@@ -104,6 +104,8 @@ Advanced users can set up the VPN server on a $35
\* Debian 10 users should use the standard Linux kernel (not the "cloud" version). Read more here. If using Debian 10 on EC2, you must first switch to the standard Linux kernel before running the VPN setup script.
+
+\*\* Support for CentOS Linux 8 will end on December 31, 2021. Read more here.
:warning: **DO NOT** run these scripts on your PC or Mac! They should only be used on a server!
diff --git a/aws/README-zh.md b/aws/README-zh.md
index 0e811d1..20ce0ee 100644
--- a/aws/README-zh.md
+++ b/aws/README-zh.md
@@ -8,7 +8,7 @@
- Amazon EC2 实例类型
> **注：** 在某些 AWS 区域中，此模版提供的某些实例类型可能不可用。比如 `m5a.large` 可能无法在 `ap-east-1` 区域部署（仅为假设）。在此情况下，你会在部署过程中遇到此错误：`The requested configuration is currently not supported. Please check the documentation for supported configurations`。新开放的 AWS 区域更容易出现此问题，因为它们提供的实例类型较少。如需了解更多关于实例可用性的信息，请参见 [https://ec2instances.info](https://ec2instances.info)。
-- VPN 服务器的操作系统（Ubuntu 20.04/18.04/16.04, Debian 9, CentOS 8/7, Amazon Linux 2）
+- VPN 服务器的操作系统（Ubuntu 20.04/18.04, Debian 9, CentOS 8/7, Amazon Linux 2）
> **注：** 在 EC2 上使用 Debian 9 映像之前，你需要先在 AWS Marketplace 上订阅：[Debian 9](https://aws.amazon.com/marketplace/pp/B073HW9SP3)。
- 你的 VPN 用户名
- 你的 VPN 密码
diff --git a/aws/README.md b/aws/README.md
index 3708d3c..9d7f300 100644
--- a/aws/README.md
+++ b/aws/README.md
@@ -8,7 +8,7 @@ Available customization parameters:
- Amazon EC2 instance type
> **Note**: It is possible that not all instance type options offered by this template are available in a specific AWS region. For example, you may not be able to deploy an `m5a.large` instance in `ap-east-1` (hypothetically). In that case, you might experience the following error during deployment: `The requested configuration is currently not supported. Please check the documentation for supported configurations`. Newly released regions are more prone to having this problem as there are less variety of instances. For more info about instance type availability, refer to [https://ec2instances.info](https://ec2instances.info).
-- OS for your VPN server (Ubuntu 20.04/18.04/16.04, Debian 9, CentOS 8/7, Amazon Linux 2)
+- OS for your VPN server (Ubuntu 20.04/18.04, Debian 9, CentOS 8/7, Amazon Linux 2)
> **Note:** Before using the Debian 9 image on EC2, you need to first subscribe at the AWS Marketplace: [Debian 9](https://aws.amazon.com/marketplace/pp/B073HW9SP3).
- Your VPN username
- Your VPN password
diff --git a/azure/README-zh.md b/azure/README-zh.md
index 02e0820..898c5af 100644
--- a/azure/README-zh.md
+++ b/azure/README-zh.md
@@ -9,7 +9,7 @@
- Username for VPN **and** SSH （用户名）
- Password for VPN **and** SSH （密码）
- IPsec Pre-Shared Key for VPN （IPsec 预共享密钥）
- - Operating System Image （操作系统镜像，Ubuntu 20.04/18.04/16.04 或 Debian 9）
+ - Operating System Image （操作系统镜像，Ubuntu 20.04/18.04 或 Debian 9）
- Virtual Machine Size （虚拟机大小，默认值： Standard_B1s）
**注：** \*不要\* 在值中使用这些字符： `\ " '`
diff --git a/azure/README.md b/azure/README.md
index 7f5bfdd..b0faa2c 100644
--- a/azure/README.md
+++ b/azure/README.md
@@ -9,7 +9,7 @@ Customizable with the following options:
- Username for VPN **and** SSH
- Password for VPN **and** SSH
- IPsec Pre-Shared Key for VPN
- - Operating System Image (Ubuntu 20.04/18.04/16.04 or Debian 9)
+ - Operating System Image (Ubuntu 20.04/18.04 or Debian 9)
- Virtual Machine Size (Default: Standard_B1s)
**Note:** DO NOT use these special characters within values: `\ " '`