Upgrade OpenSSH Server on Ubuntu

Upgrade OpenSSH Server on Ubuntu.md

References:

• Upgrade OpenSSH Server on your Ubuntu Distro manually (tested omn 22.04 LTS)
• Releases

Step 1: Download the Latest Version

wget https://ftp.openbsd.org/pub/OpenBSD/OpenSSH/portable/openssh-9.9p2.tar.gz

Step 2: Remove the Existing Installation

sudo systemctl stop sshd
sudo apt-get remove openssh-server openssh-client

Step 3: Install Build Tools

sudo apt update
sudo apt install -y build-essential zlib1g-dev libssl-dev libpam0g-dev libselinux1-dev libwrap0-dev libedit-dev libbsd-dev autoconf automake libtool pkg-config wget curl git
```bash

Step 4: Build and Install OpenSSH
```bash
tar zxvf openssh-9.9p2.tar.gz
cd openssh-9.9p2
./configure
make
sudo make install
```bash

Step 5: Set Up the Service
```bash
sudo vim /etc/systemd/system/sshd.service
# Paste the following content into the file:
[Unit]
Description=OpenSSH server daemon
After=network.target

[Service]
ExecStart=/usr/local/sbin/sshd -D
ExecReload=/bin/kill -HUP $MAINPID
KillMode=process
Restart=on-failure

[Install]
WantedBy=multi-user.target

Step 6: Reload the Daemon and Start the Service

sudo systemctl daemon-reload
sudo systemctl start sshd
sudo systemctl enable sshd

Step 7: Unmask SSH if Needed

sudo systemctl unmask ssh
sudo systemctl daemon-reload
sudo systemctl start sshd
sudo systemctl enable sshd
sudo systemctl status sshd