Category: Linux

Restart Services in Xampp Linux

You can restart services on xampp linux using

/opt/lampp/lampp

To restart, use

/opt/lampp/lampp restart

Here are other available options

root@ip-172-31-36-153:~# /opt/lampp/lampp --help
Usage: lampp 

	start         Start XAMPP (Apache, MySQL and eventually others)
	startapache   Start only Apache
	startmysql    Start only MySQL
	startftp      Start only ProFTPD

	stop          Stop XAMPP (Apache, MySQL and eventually others)
	stopapache    Stop only Apache
	stopmysql     Stop only MySQL
	stopftp       Stop only ProFTPD

	reload        Reload XAMPP (Apache, MySQL and eventually others)
	reloadapache  Reload only Apache
	reloadmysql   Reload only MySQL
	reloadftp     Reload only ProFTPD

	restart       Stop and start XAMPP
	security      Check XAMPP's security

	enablessl     Enable SSL support for Apache
	disablessl    Disable SSL support for Apache

	backup        Make backup file of your XAMPP config, log and data files

	oci8          Enable the oci8 extenssion

	panel         Starts graphical XAMPP control panel

root@ip-172-31-36-153:~#

See Auto start XAMPP on Boot

November 30, 2019

Remove SSH Private Key Passphrase
To remove SSH private key passphrase, run
```
ssh-keygen -p -f SSH_PRIVATE_KEY_FILE
```
Example

Method 2

You can use OpenSSL to remove passphase with
```
openssl rsa -in PRIVATE_KEY_WITH_PW.key -out PRIVATE_KEY_NO_PW.key
```
See SSH
November 28, 2019
VestaCP redirect webmail to HTTPS
To always force webmail to use HTTP on VeataCP, edit file
```
vi /etc/roundcube/defaults.inc.php
```
Find
```
$rcmail_config['force_https'] = false;
```
Replace with
```
$rcmail_config['force_https'] = true;
```
November 25, 2019

Prometheus Node Exporter on non default port

To run Prometheus Node Exporter on custom port, use

/usr/local/bin/node_exporter --web.listen-address=:9101

Here is systemctl service script i used

[root@cdn 1945]# cat /etc/systemd/system/node_exporter.service
[Unit]
Description=Node Exporter
Wants=network-online.target
After=network-online.target

[Service]
User=node_exporter
Group=node_exporter
Type=simple
ExecStart=/usr/local/bin/node_exporter --web.listen-address=:9101

[Install]
WantedBy=multi-user.target
[root@cdn 1945]#

Related Posts

Prometheus

Server Monitoring

November 23, 2019

Install Nginx on CentOS 8

To install Nginx web server on CentOS 8, create repo

vi /etc/yum.repos.d/nginx.repo

Add

[nginx]
name=nginx repo
baseurl=http://nginx.org/packages/centos/$releasever/$basearch/
gpgcheck=0
enabled=1

Install nginx with dnf or yum

dnf install nginx

Open HTTP and HTTPS ports on firewall

firewall-cmd --zone=public --permanent --add-service=http
firewall-cmd --zone=public --permanent --add-service=https
firewall-cmd --zone=public --permanent --add-service=ssh
firewall-cmd --reload

November 21, 2019

Monitor Server with Prometheus and Grafana
Prometheus is used an open source software, that can collect metrics and alerting.

You can download latest version oof Prometheus from

https://prometheus.io/download/

Create a user
```
useradd --no-create-home --system --shell /bin/false prometheus
```
Download and Install prometheus
```
cd /usr/local/src
wget https://github.com/prometheus/prometheus/releases/download/v2.31.0-rc.1/prometheus-2.31.0-rc.1.linux-amd64.tar.gz
tar xvf prometheus-2.31.0-rc.1.linux-amd64.tar.gz
cd prometheus-2.31.0-rc.1.linux-amd64
mv prometheus /usr/local/bin/
mv promtool /usr/local/bin/
mkdir /etc/prometheus
mkdir /var/lib/prometheus
mv consoles /etc/prometheus
mv console_libraries /etc/prometheus
mv prometheus.yml /etc/prometheus
chown prometheus:prometheus /etc/prometheus
chown prometheus:prometheus /var/lib/prometheus
```
Create a service file
```
vi /etc/systemd/system/prometheus.service
```
Add following content
```
[Unit]
Description=Prometheus
Wants=network-online.target
After=network-online.target

[Service]
User=prometheus
Group=prometheus
Type=simple
ExecStart=/usr/local/bin/prometheus \
    --config.file /etc/prometheus/prometheus.yml \
    --storage.tsdb.path /var/lib/prometheus/ \
    --web.console.templates=/etc/prometheus/consoles \
    --web.console.libraries=/etc/prometheus/console_libraries

[Install]
WantedBy=multi-user.target
```
Enable prometheus to start on boot
```
systemctl enable prometheus
```
Start prometheus
```
systemctl start prometheus
systemctl status prometheus
```
Prometheus runs on port 9090, you can access promethus at
```
http://YOUR_SERVER_IP:9090/graph
```
It will look like

Prometheus have some basic graphing features, but you can’t use it for monitoring. To create dash board and monitor, you need to use grafana.

Collecting Data

Node Exporter is used to collect data from servers. All monitored servers need Node Exporter installed. You can download latest version of NodeExporter from

https://github.com/prometheus/node_exporter/releases

Lets create a user for Node Exporter to run
```
useradd --no-create-home --system --shell /bin/false node_exporter
```
Install Node Exporter
```
cd /usr/local/src
wget https://github.com/prometheus/node_exporter/releases/download/v1.2.2/node_exporter-1.2.2.linux-amd64.tar.gz
tar xvf node_exporter-1.2.2.linux-amd64.tar.gz
cd /usr/local/src/node_exporter-1.2.2.linux-amd64/
mv node_exporter /usr/local/bin/
```
Create a systemd service file for node exporter
```
vi /etc/systemd/system/node_exporter.service
```
Add
```
[Unit]
Description=Node Exporter
Wants=network-online.target
After=network-online.target

[Service]
User=node_exporter
Group=node_exporter
Type=simple
ExecStart=/usr/local/bin/node_exporter

[Install]
WantedBy=multi-user.target
```
Enable and start Node Exporter
```
systemctl enable node_exporter
systemctl start node_exporter
systemctl status node_exporter
```
Node Exporter run on port 9100 and expose system metrics on url
```
http://SERVER_IP:9100/metrics
```
Adding Servers to Prometheus

Once Node Exporter installed on a server, you need to tell Prometheus to get data from the Node Exporter you just installed. To do this, edit Prometheus configuration file.
```
vi /etc/prometheus/prometheus.yml
```
Add following
```
  - job_name: 'node_exporter'
    scrape_interval: 5s
    static_configs:
      - targets: ['SERVER_IP:9100']
```
To monitor multiple servers, you can dd more servers in targets line. Here is an example config

https://gist.github.com/serverok/83a622e7577da36384f87fe60c9930af/raw

Restart prometheus
```
systemctl restart prometheus
```
Grafana

Grafana is used to visualise data collected by Prometheus. You can download Grafana from

https://grafana.com/grafana/download

Grafana offers free cloud hosted version with some limitation (1 user, 5 dashboards). Free version is suitable if you are getting started and don’t want to install your own. You can signup for cloud hosted version at

https://grafana.com/get

If you decide to install your own Grafana, you can run
```
cd /usr/local/src
wget https://dl.grafana.com/oss/release/grafana_7.3.7_amd64.deb
dpkg -i grafana_7.3.7_amd64.deb
```
Enable and start grafana
```
systemctl enable grafana-server
systemctl start grafana-server
systemctl status grafana-server
```
If you did your own install, grafana runs on port 3000. To access, use url
```
http://SERVER_IP:3000/login
```
Default username and passwords are “admin”. Once logged in you will be asked to set password for grafana admin user.

Before you can use Grafana, you need to set a data source and create dash board. In our case, data source is prometheus. To connect Grafana to your Prometheus insallation, go to Settings > Data Sources

On next page, select Prometheus

On next page, for URL, enter http://PROMETHUS_SERVER_IP:9090, scroll down, click on “Save & Test” button. If grafana can connect to your prometheus installation, you should see success message with “Data source is working”. If not, you need to check your firewall rules.

Creating Grafana Dashboards

Grafana displays data in dash boards. You can create your own or use pre existing dash boards. You can find pre-made dash boards at

https://grafana.com/grafana/dashboards

On my grafana installation, i used dashboard

https://grafana.com/grafana/dashboards/11074

To add this dash board to your Grafana, click on the + button, then select Import. On next screen, you can enter ID for the dash board you need to import. In this case 11074. Click “Load” button to import the dash board.

Here is a dash board for one of the server

You can edit Panels in grafana dash board to see how it is created. You can create a new dash board with panel you need. This way your dashboards only show required information.

Related Posts

Server Monitoring

Prometheus Node Exporter on non default port
Prometheus init script for CentOS 6
November 18, 2019

PHP Script to monitor Apache/php-fpm

I moved a web site to new dedicated server. But for some reason, php-fpm crashed. I increased the max_children settings, but it happend again. I do not want down time while i am investigating the problem. So i created a PHP script, that will check if site is working or not.

Script have 2 part.

health-check.php

It is simple PHP script, that get a param and print it.

This file is placed on root of your web site, so it can be accessed using URL http://yoursite/health-check.php

monitor-server.php

Create

mkdir  /usr/serverok/
vi  /usr/serverok/monitor-server.php

Add following content

On the script, replace YOUR_DOMAIN_HERE with your actual domain name.

systemctl restart apache2 is for restart apache web server. If you use nginx, replace it. systemctl restart php7.2-fpm restart php-fpm, if you have differnt version of php, you need to change it.

The script is generate a random number, pass it to health-check.php script. Compared the value returned with generated random number to make sure the value is correct. If web server or php-fpm fail, this check will fail.

Now set a cronjob

crontab -e

Add

*/5 * * * * /usr/bin/php /usr/serverok/monitor-server.php

Related Posts

Server Monitoring

November 16, 2019

Split Large file into smaller files
Today I was transferring a large 7 GB backup file into another server. Every time I copy it gets disconnected after some time and I have to transfer again. When transferring large files, it is better to split it into smaller files, this way if one of the file transfers failed, you only need to transfer this specific file again. With rsync, it make it easy as you can sync all files to remote server.

How to Split large CSV file into smaller files

To split a large file into smaller parts, run
```
split -b 500MB  LARGE_FILE.tar.gz
```
This command will split a large file into smaller files with 500 MB size each. You can specify a different size if you need.

Once all files are on the new server, you can combine them into one file with the command
```
cat * > LARGE_FILE.tar.gz
```
When you do cat *, make sure only split files are in the current folder.

Related Posts

tar
rsync
November 12, 2019

ISPConfig fail to create MySQL database

Whem creating MySQL database in ISPConfig, no database get created. To debug, i disabled the cronjob. Created a database in ISPConfig control panel, run cronjob manually, it shows following error

[root@vs-sok ~]# /usr/local/ispconfig/server/server.sh
PHP Warning:  mysqli::mysqli(): (28000/1045): Access denied for user 'root'@'localhost' (using password: YES) in /usr/local/ispconfig/server/plugins-available/mysql_clientdb_plugin.inc.php on line 528
11.11.2019-13:45 - ERROR - Unable to connect to mysqlAccess denied for user 'root'@'localhost' (using password: YES)
PHP Warning:  mysqli::mysqli(): (28000/1045): Access denied for user 'root'@'localhost' (using password: YES) in /usr/local/ispconfig/server/plugins-available/mysql_clientdb_plugin.inc.php on line 184
11.11.2019-13:45 - ERROR - Unable to connect to mysqlAccess denied for user 'root'@'localhost' (using password: YES)
finished.
[root@vs-sok ~]# /usr/local/ispconfig/server/server.sh
PHP Warning:  mysqli::mysqli(): (28000/1045): Access denied for user 'root'@'localhost' (using password: YES) in /usr/local/ispconfig/server/plugins-available/mysql_clientdb_plugin.inc.php on line 472
11.11.2019-13:46 - ERROR - Unable to connect to mysql: Access denied for user 'root'@'localhost' (using password: YES)
finished.
[root@vs-sok ~]#

This is because ISPConfig can’t connect to MySQL server for creating new MySQL database. To fix, edit file /usr/local/ispconfig/server/lib/mysql_clientdb.conf

vi /usr/local/ispconfig/server/lib/mysql_clientdb.conf

Update MySQL password for user root on this file. The content of the file look like

Related Posts

ISPConfig

November 11, 2019

Install SSL for ISPConfig Control Panel

To add SSL for ISPConfig control panel, add the server hostname as a website in ISPConfig and enable the LetsEnrypt checkbox. You can find the server hostname with the command

hostname -f

That will get SSL installed for your hostname. You need to point the server hostname to the server’s IP address to get SSL certificate. Visit server hostname subdomain in a browser and verify SSL works.

Once you have a valid LetsEncrypt SSL certificate installed on your site, create a file

mkdir /usr/serverok/
vi /usr/serverok/ssl-hostname-renew

Add the following content to the file

#!/bin/bash

cat /etc/letsencrypt/live/$(hostname -f)/fullchain.pem > /usr/local/ispconfig/interface/ssl/ispserver.crt
cat /etc/letsencrypt/live/$(hostname -f)/privkey.pem > /usr/local/ispconfig/interface/ssl/ispserver.key
cat /usr/local/ispconfig/interface/ssl/ispserver.{key,crt} > /usr/local/ispconfig/interface/ssl/ispserver.pem
chmod 600 /usr/local/ispconfig/interface/ssl/ispserver.pem
systemctl restart apache2

cat /usr/local/ispconfig/interface/ssl/ispserver.crt > /etc/postfix/smtpd.cert
cat /usr/local/ispconfig/interface/ssl/ispserver.key > /etc/postfix/smtpd.key
service postfix restart
service dovecot restart

cat /usr/local/ispconfig/interface/ssl/ispserver.pem > /etc/ssl/private/pure-ftpd.pem
chmod 600 /etc/ssl/private/pure-ftpd.pem
service pure-ftpd-mysql restart

If you use nginx webserver, replace apache2 with nginx.

Make the script executable

chmod 755 /usr/serverok/ssl-hostname-renew

Run the script to activate SSL for the ISPConfig control panel, FTP, and mail server.

/usr/serverok/ssl-hostname-renew

Now set a cronjob

crontab -e

Add

@weekly /usr/serverok/ssl-hostname-renew > /dev/null

Now you should be able to access ISPConfig with a valid SSL certificate on URL

https://HOSTNAME:8080

Back to ISPconfig

November 9, 2019

VestaCP SSL for mail server
VestaCP install self signed SSL for mail server by default. To install valid SSL, login to VestCP, go to sites. You will see a site with your sites hostname. If you don’t see it, create a site with your server hostname. Make sure DNS edited so hostname resolve to server IP. Now you should be able to get free LetsEncrypt SSL for this site.

if you check Apache Virtual Host for the site, you will see someting like
```
SSLCertificateFile /home/admin/conf/web/ssl.HOSTNAME.crt
SSLCertificateKeyFile /home/admin/conf/web/ssl.HOSTNAME.key
SSLCertificateChainFile /home/admin/conf/web/ssl.HOSTNAME.ca
```
In VeataCP the config files for exim and dovecot located at
```
/etc/exim4/exim4.conf.template
/etc/dovecot/conf.d/10-ssl.conf
```
These configs use SSL located at /usr/local/vesta/ssl/certificate.crt and /usr/local/vesta/ssl/certificate.key.

To use the FREE SSL, create a bash script.
```
mkdir /usr/serverok/
vi /usr/serverok/ssl-renew-hostname
```
Add
```
#!/bin/bash
# Author: ServerOk Software
# Web: www.serverok.in
# Email: [email protected]

cat /home/admin/conf/web/ssl.HOSTNAME.crt > /usr/local/vesta/ssl/certificate.crt
cat /home/admin/conf/web/ssl.HOSTNAME.ca >> /usr/local/vesta/ssl/certificate.crt
cat /home/admin/conf/web/ssl.HOSTNAME.key > /usr/local/vesta/ssl/certificate.key
systemctl restart apache2
systemctl restart exim4
systemctl restart dovecot
/usr/local/vesta/nginx/sbin/vesta-nginx -s reload
```
make the file executable
```
chmod 755 /usr/serverok/ssl-renew-hostname
```
Run the script
```
/usr/serverok/ssl-renew-hostname
```
Now SSL will work for mail server and VestaCP. To access VestaCP, use
```
https://HOSTNAME:8083/login/
```
Verify Mail Server SSL

You can view mail server SSL with command
```
openssl s_client -showcerts -connect HOSTNAME:993
openssl s_client -showcerts -connect HOSTNAME:465
openssl s_client -starttls smtp -showcerts -connect HOSTNAME:587
```
Replace HOSTNAME with actual hostname of your server.

Auto Renew SSL

LetsEncrypt SSL expire every 90 days. So we will create a cronjob to auto renew SSL. Ff you have a paid SSL, you don’t need this cronjob

Create a cronjob with
```
crontab -e
```
Add
```
@weekly  /usr/serverok/ssl-renew-hostname > /dev/null 2>&1
```
Related Posts

VestaCP Free Hosting Control Panel
November 8, 2019
Disable Native Notification on Google Chrome Ubuntu
On Ubuntu, Google chrome had a disable native notification option. On Chrome 78, this option is removed. But you still can manually enable it.

To enbale chrome notification, edit file
```
gedit ~/.config/google-chrome/Local\ State
```
Find
```
"tab-hover-cards@4"
```
Replace with
```
"enable-native-notifications@2","tab-hover-cards@4"
```
Save and exit the file. Now restart google chrome.

Related Posts

Google Chrome
November 8, 2019

Category: Linux

Collecting Data

Adding Servers to Prometheus

Grafana

Creating Grafana Dashboards

Verify Mail Server SSL

Auto Renew SSL