Ktor VPS Server Deployment Steps

DeploymentSteps.txt

1. Download Git Bash (only if on Windows)

2. Go to your users folder and open the .ssh folder. Then open Git Bash / Terminal there and generate a key pair:
ssh-keygen -m PEM -t rsa -b 2048

3. Copy the key to your server:
ssh-copy-id -i <keyname> <user>@<host>

5. Login to your Ubuntu server via SSH:
ssh -i <keyname> <user>@<host>

6. Update dependencies:
sudo apt update

7. Install Java:
sudo apt-get install default-jdk

8. Open /etc/ssh/sshd_config:
sudo nano /etc/ssh/sshd_config

9. Put this string in there, save with Ctrl+S and exit with Ctrl+X:
KexAlgorithms curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha1,diffie-hellman-group-exchange-sha1,diffie-hellman-group1-sha1

10. Restart the sshd service:
sudo systemctl restart sshd

11. Create a systemd service for your Ktor server:
sudo nano /etc/systemd/system/chat.service

12. Paste this configuration in this service, then save with Ctrl+S and exit with Ctrl+X:
[Unit]
Description=Chat Service
After=network.target
StartLimitIntervalSec=10
StartLimitBurst=5

[Service]
Type=simple
Restart=always
RestartSec=1
User=root
ExecStart=sudo java -jar /root/chat/chat-server.jar

[Install]
WantedBy=multi-user.target

13. Launch the service:
sudo systemctl start chat

14. Create a symlink to automatically launch the service on boot up:
sudo systemctl enable chat

15. Make sure, your ports are open and you forward the traffic from the standard HTTP port to 8080:
iptables -t nat -I PREROUTING -p tcp --dport 80 -j REDIRECT --to-ports 8080
sudo iptables -A INPUT -p tcp --dport 80 -j ACCEPT
sudo iptables -A INPUT -p tcp --dport 8080 -j ACCEPT

16. Then, save your iptables rules:
sudo apt-get install iptables-persistent

17. Install MongoDB
apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 9DA31620334BD75D9DCB49F368818C72E52529D4
echo "deb [ arch=amd64 ] https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.0 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb.list
apt-get update
apt-get install mongodb-org
systemctl unmask mongod
systemctl enable mongod
systemctl restart mongod

18. Make sure the folder /root/chat/ exists
cd /root
mkdir chat