Update install.md (#650)

remove support Ubuntu 20.04

Author: kudriavitsky

content/nap-waf/v4/admin-guide/install.md

@@ -33,7 +33,7 @@ NGINX App Protect WAF supports the following operating systems:
 - [Oracle Linux 8.1.x and above](#oracle-linux-81-installation)
 - [RHEL 8.1.x and above](#rhel-81-installation)
 - [RHEL 9 and above](#rhel-9-installation)
-- [Ubuntu 20.04 (Focal), 22.04 (Jammy) & 24.04 (Noble)](#ubuntu-installation)
+- [Ubuntu 22.04 (Jammy) & 24.04 (Noble)](#ubuntu-installation)
 
 The NGINX App Protect WAF package has the following dependencies:
 
@@ -870,7 +870,7 @@ If a user other than **nginx** is to be used, note the following:
     app-protect=23+3.263.0-1~[OS_CODENAME]
     ```
 
-    Replace the [OS_CODENAME] in above the example with **focal** for Ubuntu 20.04, **jammy** for Ubuntu 22.04 and **noble** for Ubuntu 24.04.
+    Replace the [OS_CODENAME] in above the example with **jammy** for Ubuntu 22.04 and **noble** for Ubuntu 24.04.
     <br>
     <br>
 
@@ -917,7 +917,7 @@ If a user other than **nginx** is to be used, note the following:
     /opt/app_protect/bin/iprepd /etc/app_protect/tools/iprepd.cfg > ipi.log 2>&1 &
     ```
 
-{{< note >}} Ubuntu 20.04 / Ubuntu 22.04 / Ubuntu 24.04 activates **AppArmor** by default, but NGINX App Protect WAF will run in unconfined mode after being installed as it is shipped with no AppArmor profile. To benefit from AppArmor access control capabilities for NGINX App Protect WAF, you will have to write your own AppArmor profile for NGINX App Protect WAF executables found in `/opt/app_protect/bin` such that it best suits your environment.
+{{< note >}} Ubuntu 22.04 / Ubuntu 24.04 activates **AppArmor** by default, but NGINX App Protect WAF will run in unconfined mode after being installed as it is shipped with no AppArmor profile. To benefit from AppArmor access control capabilities for NGINX App Protect WAF, you will have to write your own AppArmor profile for NGINX App Protect WAF executables found in `/opt/app_protect/bin` such that it best suits your environment.
 {{< /note >}}
 
 ## Docker Deployments
@@ -1333,7 +1333,7 @@ CMD ["sh", "/root/entrypoint.sh"]
 ARG OS_CODENAME
 # Where OS_CODENAME can be: focal/jammy/noble
 # syntax=docker/dockerfile:1
-# For Ubuntu 20.04 / 22.04 / 24.04:
+# For Ubuntu 22.04 / 24.04:
 FROM ubuntu:${OS_CODENAME}
 
 # Install prerequisite packages:
@@ -1664,13 +1664,13 @@ RUN --mount=type=secret,id=nginx-crt,dst=/etc/ssl/nginx/nginx-repo.crt,mode=0644
     apt-get update && DEBIAN_FRONTEND="noninteractive" apt-get install -y app-protect-compiler
 ```
 
-### Ubuntu 20.04 / Ubuntu 22.04 / Ubuntu 24.04 Converter Docker Deployment Example
+### Ubuntu 22.04 / Ubuntu 24.04 Converter Docker Deployment Example
 
 ```dockerfile
 ARG OS_CODENAME
 # Where OS_CODENAME can be: bionic/focal/jammy/noble
 # syntax=docker/dockerfile:1
-# For Ubuntu 20.04 /22.04 / 24.04:
+# For Ubuntu 22.04 / 24.04:
 FROM ubuntu:${OS_CODENAME}
 
 # Install prerequisite packages:
@@ -2041,7 +2041,7 @@ For Debian 12:
 sudo apt-get install app-protect-attack-signatures=2020.04.30-1~bookworm
 ```
 
-### Ubuntu 20.04 / Ubuntu 22.04
+### Ubuntu 22.04 / Ubuntu 24.04
 
 1. Add NGINX App Protect WAF Security Updates repository:
 
@@ -2076,12 +2076,6 @@ sudo apt-get install app-protect-attack-signatures=2020.04.30-1~bookworm
 sudo apt-cache policy app-protect-attack-signatures
 ```
 
-For Ubuntu 20.04:
-
-```shell
-sudo apt-get install app-protect-attack-signatures=2020.07.16-1~focal
-```
-
 For Ubuntu 22.04:
 
 ```shell
@@ -2294,7 +2288,7 @@ sudo apt-get install app-protect-threat-campaigns=2020.06.25-1~bullseye
 sudo apt-get install app-protect-threat-campaigns=2020.06.25-1~bookworm
 ```
 
-### Ubuntu 20.04 / Ubuntu 22.04
+### Ubuntu 22.04
 
 1. If not already configured, add the NGINX App Protect WAF Security Updates repository:
 
@@ -2500,7 +2494,7 @@ The App Protect Bot Signatures is named: app-protect-bot-signatures and it is a
     ```
 
 
-### Ubuntu 20.04 / Ubuntu 22.04
+### Ubuntu 22.04
 
 1. If not already configured, add the NGINX App Protect WAF Security Updates repository:
 
@@ -2578,7 +2572,7 @@ You can uninstall the App Protect in below Operating Systems by using the follow
 sudo dnf remove app-protect app-protect-selinux
 ```
 
-### Debian 11 / Debian 12 / Ubuntu 20.04 / Ubuntu 22.04 / Ubuntu 24.04
+### Debian 11 / Debian 12 / Ubuntu 22.04 / Ubuntu 24.04
 
 ```shell
 sudo apt-get remove app-protect \
@@ -2640,7 +2634,7 @@ app-protect=27+3.1088.2-1~[OS_CODENAME]
 
 **Note**: Replace the [OS_CODENAME] in the above command with **bullseye** for Debian 11 and **bookworm** for Debian 12.
 
-### Ubuntu 20.04 / Ubuntu 22.04
+### Ubuntu 22.04
 
 1. Get the dependencies and their versions to be upgraded to by using the command:
 
@@ -2660,7 +2654,7 @@ app-protect=27+3.1088.2-1~[OS_CODENAME]
     app-protect=27+3.1088.2-1~[OS_CODENAME]
     ```
 
-**Note**: Replace the [OS_CODENAME] in the above command with **focal** for Ubuntu 20.04, **jammy** for Ubuntu 22.04, and **noble** for Ubuntu 24.04.
+**Note**: Replace the [OS_CODENAME] in the above command with **jammy** for Ubuntu 22.04, and **noble** for Ubuntu 24.04.
 
 ## Upgrading App Protect to the latest version
 
@@ -2672,7 +2666,7 @@ Upgrade the NGINX App Protect WAF to the latest 4.x version:
 sudo dnf -y update app-protect
 ```
 
-### Debian 11 / Debian 12 / Ubuntu 20.04 / Ubuntu 22.04
+### Debian 11 / Debian 12 / Ubuntu 22.04
 
 Upgrade the NGINX App Protect WAF to the latest 4.x version: