Category: Linux

logrotate nginx log by date

Logrotate by default rotate logs with numbers like following

You can configure how many logs to keep and how to rotate lots by editing logrotate configuration file for nginx

root@ok:~# cat /etc/logrotate.d/nginx 
/var/log/nginx/*.log {
	daily
	missingok
	rotate 14
	compress
	delaycompress
	notifempty
	create 0640 www-data adm
	sharedscripts
	prerotate
		if [ -d /etc/logrotate.d/httpd-prerotate ]; then \
			run-parts /etc/logrotate.d/httpd-prerotate; \
		fi \
	endscript
	postrotate
		invoke-rc.d nginx rotate >/dev/null 2>&1
	endscript
}
root@ok:~#

rotate 14 – this tells logrotate to keep logs for 14 days.

If you need to rotate logs by date, add

        dateext
        dateformat -%Y-%m-%d

Example

/var/log/nginx/*.log {
        daily
        missingok
        rotate 14
        compress
        delaycompress
        notifempty
        create 0640 www-data adm
        dateext
        dateformat -%Y-%m-%d
        sharedscripts
        prerotate
                if [ -d /etc/logrotate.d/httpd-prerotate ]; then \
                        run-parts /etc/logrotate.d/httpd-prerotate; \
                fi \
        endscript
        postrotate
                invoke-rc.d nginx rotate >/dev/null 2>&1
        endscript
}

See Logrotate

July 15, 2020

Attack

Stop xmlrpc.php attack on Cpanel Server

July 15, 2020
CentovaCast Enable SSL for shoutcast
To enable SSL for stream, you can use nginx reverse proxy.

In this case, i have a stream available on

http://my-domain.com:8000/index.html?sid=1

I want to make it available using SSL at

https://my-domain.com:9000/index.html?sid=1

The port will need to be differnt as you can’t run both HTTP and HTTPS on same port. So i used Port 8000 here. All traffic to this port using HTTPS will be forwarded to HTTP port. To do this install nginx
```
yum install nginx
```
Add a virtual host configuration at
```
vi /etc/nginx/conf.d/port8000.conf 
```
with following content
```
server {
    listen       8000 ssl;
    server_name  your-domain.com;
    root         /usr/share/nginx/html;
    ssl_certificate /etc/letsencrypt/live/your-domain.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/your-domain.com/privkey.pem;
    # include /etc/letsencrypt/options-ssl-nginx.conf;
    # ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem;
    proxy_read_timeout 600s;
    location / {
        proxy_set_header X-Real-IP  $remote_addr;
        proxy_set_header X-Forwarded-For $remote_addr;
        proxy_set_header Host $host;
        proxy_pass http://YOUR_IP_HERE:8000;
    }
}
```
Now restart nginx
```
systemctl restart nginx
```
Auto restart Nginx

Since we used free LetsEncrypt SSL for the domain, you will need to auto restart Nginx. This can be done by adding a cronjon
```
@weekly systemctl restart nginx
```
You may also need to add cronjob for renewing SSL, this you can find at https://serverok.in/letsencrypt. In case of CentovaCast, SSL is managed by CentovaCast, so you need to worry about auto renewing SSL certificate.
July 11, 2020
Install Pure-FTPd from source
To instal pureftpd from source, go to

http://download.pureftpd.org/pub/pure-ftpd/releases/

find latest version download link.

Download and Install

At the time of this post, latest version is 1.0.49, always use latest version when you are installing.
```
cd /usr/local/src
wget https://download.pureftpd.org/pub/pure-ftpd/releases/pure-ftpd-1.0.49.tar.gz
tar -zxvf pure-ftpd-1.0.49.tar.gz
cd pure-ftpd-1.0.*
./configure --with-puredb
make
make check
make install
```
The software is now installed in /usr/local/sbin/pure-ftpd

To start the server, just run the following command
```
/usr/local/sbin/pure-ftpd
```
Common Errors during install

If you get error: no acceptable C compiler found in $PATH, install gcc with
```
yum install gcc -y
```
Firewall

FTP need following ports open in firewall.
```
TCP 21
TCP 30000-50000
```
Enable MySQL support

If you need to enable MySQL support in pure-ftpd, then run configure command with following option.
```
./configure --with-mysql --with-uploadscript --with-extauth
```
Configuration Files

During installation, configuration file get copied to
```
/etc/pure-ftpd.conf
```
You can edit it as required.

To start pure-ftpd with configuration file, run
```
/usr/local/sbin/pure-ftpd /etc/pure-ftpd.conf
```
To enable system users login, set UnixAuthentication to yes.
```
UnixAuthentication            yes
MinUID                      100
```
MinUID specify lowest id of users that is allowed to login to user. You can uncomment it if you need user root or any other system users to login. But this maybe insecure as FTP comminication is done with out encryption.

NAT

If you are behind NAT, you need to uncomment following settings. This is required for most cloud providers like Amazon AWS, Google Cloud, Microsoft Azure. To see if you have NAT, see if your Public IP is configured inside your server. You can list IP configured in your server with command ip a
```
PassivePortRange             30000 50000
ForcePassiveIP               192.168.0.1
```
Replace 192.168.0.1 with your public IP. If you are using Amazon AWS, then it will be your Elastic IP address. If you don’t use Elastic IP, then it is your public IP.

See PureFTPd
July 8, 2020
Hacking

expoloit-db.com contact many 0 day vlunerability and security related papers.

https://www.exploit-db.com

July 5, 2020
pptpd

Allow PPTP VPN connection on firewalld

Back to VPN

July 2, 2020

Systemd Journal

Systemd have its own loggin system called Systemd Journal. It keep track of logs for each service.

To see log for a service, run

journalctl -u SERVICE_NAME

Example

root@ocp-serverok-in:~# journalctl -u myapp
-- Logs begin at Wed 2020-05-27 06:43:34 UTC, end at Fri 2020-06-26 09:33:19 UTC. --
Jun 26 08:53:59 ocp-serverok-in systemd[1]: Started Sample web server.
Jun 26 08:53:59 ocp-serverok-in cat[36147]: Starting web server
root@ocp-serverok-in:~#

June 26, 2020

Start an application using systemd
systemd is used to start applications on linux systems.

In this post, we will create an application and run start it on boot using systemd.

Lets create our sample application.
```
mkdir /root/myapp/
vi /root/myapp/web.sh
```
Add following content to the file and save.
```
#!/bin/bash

echo "Starting web server" | systemd-cat -p info

cd /root/myapp
python3 -m http.server 80
```
You can start the application by running following command on terminal
```
bash /root/myapp/web.sh
```
this will run a simple web server on port 80. If you already have a web server running on port 80, change the port to another.

To stop web server, type CTRL+C.

Create Systemd service file

To manage this application using systemd, we need to create a service file.
```
vi /etc/systemd/system/myapp.service
```
Add
```
[Unit]
Description=Sample web server

[Service]
Type=simple
ExecStart=/bin/bash /root/myapp/web.sh

[Install]
WantedBy=multi-user.target
```
Managing Systemd service

First you need to enable the service with
```
systemctl enable myapp
```
To start the service, run
```
systemctl start myapp
```
To stop the service, run
```
systemctl stop myapp
```
To see status of the service, run
```
systemctl status myapp
```
June 26, 2020
Application Performance Monitor (APM)

Application Performance Monitor (APM) is used to monitor application performance. This help you identify problems with your application. If you are developing an application, this is very helpful as you can see changes in application performance during a software upgrade, this allow you to identify perofrmance issues related to changes in your application.

Here are some useful sites that provide Application Performance Monitoring solutions.

https://blackfire.io

newrelic

June 24, 2020
serverpilot
serverpilot is a SAAS hosting control panel for web servers.

It use nginx as proxy with apache web server as backend. Services used by serverpilot are
```
systemctl status nginx-sp
systemctl status apache-sp
systemctl status mysql
systemctl status php7.1-fpm-sp
systemctl status php7.2-fpm-sp
systemctl status php7.3-fpm-sp
```
Config file locations
```
/etc/nginx-sp/
/etc/apache-sp/
```
Web site specific configurations are stored in the vhosts.d folder inside apache/nginx config folders.

Apache installed at
```
/opt/sp/apache/bin/apachectl start
/opt/sp/apache/bin/apachectl configtest
```
Back to Hosting Control Panel
June 20, 2020
sysdig
sysdig is a tool like top, but more powerful, it is a combination of tools like htop, iftop, lsof.

To install sysdig on ubuntu, run
```
apt-get install sysdig
```
To see files using top IO, run
```
sysdig -c topfiles_bytes
```
To access top like GU, run
```
csysdig
```
June 17, 2020

Webuzo

Install webuzo

wget -N http://files.webuzo.com/install.sh
chmod 0755 install.sh
./install.sh

After installing you can login into the Webuzo control panel at

https://server-ip:2005/

Webuzo Config files

/usr/local/apps/nginx/etc/conf.d/webuzoVH.conf - Nginx
/var/webuzo/my.conf - MySQL root password
/var/webuzo/certs - SSL certificates used by the control panel, mail server, FTP
/var/webuzo/logs - update/import logs

Back to Hosting Control Panels

June 16, 2020

Category: Linux

Auto restart Nginx

Download and Install

Common Errors during install

Firewall

Enable MySQL support

Configuration Files

NAT

Create Systemd service file

Managing Systemd service