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Monitor and analyze with Grafana, influxdb 1.8 and collectd under Ubuntu 22.04 LTS

This is an updated version of the previous version of this topic – Monitor and analyze with Grafana, influxdb 1.8 and collectd under CentOS Stream 9, but this time for Ubuntu 22.04 LTS. The article describes how to build modern analytic and monitoring solutions for system and application performance metrics. A solution, which may host all the server’s metrics and a sophisticated application, allows easy analyses of the data and powerful graphs to visualize the data.
A brief introduction to the main three software used to build the proposed solution:

Grafana – an analytics and a web visualization tool. It supports dashboards, charts, graphs, alerts, and many more.
influxdb – a time series database. Bleeding fast reads and writes and optimized for time.
collectd – a data collection daemon, which obtain metrics from the host it is started and sends the metrics to the database (i.e. influxdb). It has around 170 plugins to collect metrics.

What is the task of each tool:

collectd – gathers metrics and statistics using its plugins every 10 seconds on the host it runs and then sends the data over UDP to the influxdb using a simple text-based protocol.
influxdb – listens on an open UDP port for data coming from multiple collectd instances installed on many different devices. In this case, a Linux server running Ubuntu 22.04 LTS.
Grafana – an analytics and a web visualization tool. A web application, which connects to the InfluxDB and visualizes the time series metrics in graphs organized in dashboards. Graphs for CPU, memory, network, storage usage, and many more.
nginx to enable SSL and proxy in front of the Grafana.

The whole solution uses the Ubuntu 22.04 LTS server edition distro. Installing the Ubuntu 22.04 LTS is a mandatory step to proceed further with this article – Installation of base Ubuntu server 22.04 LTS
The UDP influxdb port should be open per IP basis and web port of the web server (nginx) is up to the purpose of the solution – it can be behind a VPN or openly accessible by Internet.

STEP 1) Install additional repositories for Grafana, InfluxDB and collectd.

collectd is part of the Ubuntu official repositories. Grafana and InfluxDB maintain their official repositories. Here is how to install them.
Add the InfluxDB repository by first, importing the key of the InfluxDB repository and add the URL of the repository in /etc/apt/sources.list.

myuser@srv:~$ sudo curl -sL https://repos.influxdata.com/influxdb.key | sudo apt-key add -
Warning: apt-key is deprecated. Manage keyring files in trusted.gpg.d instead (see apt-key(8)).
OK
echo 'deb https://repos.influxdata.com/debian stable main' > /etc/apt/sources.list.d/influxdata.list

Then, repeated the same procedure with the Grafana repository:

myuser@srv:~$ sudo curl -sL https://packages.grafana.com/gpg.key | sudo apt-key add -
Warning: apt-key is deprecated. Manage keyring files in trusted.gpg.d instead (see apt-key(8)).
OK
echo 'deb https://packages.grafana.com/oss/deb stable main' > /etc/apt/sources.list.d/grafana.list

Execute apt update to include the available file packages from all repositories including the ones:

apt update

Keep on reading!

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Monitor and analyze with Grafana, influxdb 1.8 and collectd under CentOS Stream 9

This article describes how to build a modern analytic and monitoring solutions for system and application performance metrics. A solution, which may host all the server’s metrics and a sophisticated application, allows easy analyses of the data and powerful graphs to visualize the data.
A brief introduction to the main three software used to build the proposed solution:

Grafana – an analytics and a web visualization tool. It supports dashboards, charts, graphs, alerts, and many more.
influxdb – a time series database. Bleeding fast reads and writes and optimized for time.
collectd – a data collection daemon, which obtain metrics from the host it is started and sends the metrics to the database (i.e. influxdb). It has around 170 plugins to collect metrics.

What is the task of each tool:

collectd – gathers metrics and statistics using its plugins every 10 seconds on the host it runs and then sends the data over UDP to the influxdb using a simple text-based protocol.
influxdb – listens on an open UDP port for data coming from multiple collectd instances installed on many different devices. In this case, a Linux server running CentOS Stream 9.
Grafana – an analytics and a web visualization tool. A web application, which connects to the InfluxDB and visualizes the time series metrics in graphs organized in dashboards. Graphs for CPU, memory, network, storage usage, and many more.
nginx to enable SSL and proxy in front of the Grafana.

The whole solution uses the CentOS Stream 9 Linux distro. Installing the CentOS Stream 9 is a mandatory step to proceed further with this article – Network installation of CentOS Stream 9 (20220606.0) – minimal server installation
The UDP influxdb port should be open per IP basis and web port of the web server (nginx) is up to the purpose of the solution – it can be behind a VPN or openly accessible by Internet.

STEP 1) Install additional repositories for Grafana, influxdb and collectd.

Install CentOS official EPEL and OpsTools repositories. EPEL provides additional packages to the base CentOS packages and OpsTools provides collectd and more collectd plugins than the ones included in the built-in repositories.

dnf install -y epel-release centos-release-opstools

Add the InfluxDB repository by creating a file in /etc/yum.repos.d/influxdb.repo

[influxdb]
name = InfluxDB Repository - RHEL $releasever
baseurl = https://repos.influxdata.com/centos/$releasever/$basearch/stable
enabled = 1
gpgcheck = 1
gpgkey = https://repos.influxdata.com/influxdb.key

Finally, add the Grafana repository in file /etc/yum.repos.d/grafana.repo

[grafana]
name=grafana
baseurl=https://packages.grafana.com/oss/rpm
repo_gpgcheck=1
enabled=1
gpgcheck=1
gpgkey=https://packages.grafana.com/gpg.key
sslverify=1
sslcacert=/etc/pki/tls/certs/ca-bundle.crt

Keep on reading!

Pages: 123

How To Install Linux, Apache, MySQL (MariaDB), PHP-FPM (LAMP) Stack on CentOS Stream 9

This article describes how to install a Web server with application back-end PHP and database back-end MySQL using MariaDB. In continuing the same topic, but with different software from the previous article – How To Install Linux, Nginx, MySQL (MariaDB), PHP-FPM (LEMP) Stack on CentOS Stream 9, where the Web server is Nginx with application back-end PHP-FPM, which is a sort of CGI (FastCGI). In this article, the Web server is Apache and the application is again PHP-FPM, because since the CentOS 8 the Apache mod_php is deprecated.
All the software installed throughout this article is from the CentOS Stream 9 official repositories including the EPEL repository. The machine is installed with a minimal installation of CentOS Stream 9 and there is a how-to here – Network installation of CentOS Stream 9 (20220606.0) – minimal server installation.
Here are the steps to perform:

Install, configure and start the database MariaDB.
Install, configure and start the PHP-FPM and PHP cli.
Install, configure and start the Web server Apache 2.x.
Configure the system – firewall and SELinux.
Test the installation with a phpMyAdmin installation.
Bonus – Apache HTTPS with SSL certificate – self-signed and letsencrypt.

STEP 1) Install, configure and start the database MariaDB.

First, install the MariaDB server by:

dnf install -y mariadb-server

To configure the MariaDB server, the main file is /etc/my.cnf, which just includes all files under the folder /etc/my.cnf.d/

[root@srv ~]# cat /etc/my.cnf
#
# This group is read both both by the client and the server
# use it for options that affect everything
#
[client-server]

#
# include all files from the config directory
#
!includedir /etc/my.cnf.d

[root@srv ~]# ls -altr /etc/my.cnf.d/
total 32
-rw-r--r--.  1 root root  295 Mar 25  2022 client.cnf
-rw-r--r--.  1 root root  120 May 18 07:55 spider.cnf
-rw-r--r--.  1 root root  232 May 18 07:55 mysql-clients.cnf
-rw-r--r--.  1 root root  763 May 18 07:55 enable_encryption.preset
-rw-r--r--.  1 root root 1458 Jun 13 13:24 mariadb-server.cnf
-rw-r--r--.  1 root root   42 Jun 13 13:29 auth_gssapi.cnf
drwxr-xr-x.  2 root root 4096 Oct  6 06:34 .
drwxr-xr-x. 81 root root 4096 Oct  6 06:34 ..

The most important file for the MariaDB server is /etc/my.cnf.d/mariadb-server.cnf, where all the server options are included. Under section “[mysqld]” add options to tune the MariaDB server. Supported options could be found here: https://mariadb.com/kb/en/mysqld-options/
Add the following options under “[mysqld]” in /etc/my.cnf.d/mariadb-server.cnf
Keep on reading!

Run LXC Ubuntu 22.04 LTS container with bridged network under CentOS Stream 9

In continuation of the previous article Run LXC CentOS Stream 9 container with bridged network under CentOS Stream 9, this time the LXC container will be Ubuntu 22.04 LTS Jammy Jellyfish.
To receive a better understanding why to use LXC or a much detailed information of some steps in this article it is better to visit the previously mention article and the original Run LXC CentOS 8 container with bridged network under CentOS 8.

STEP 1) Install the needed software EPEL repository and the LXC and its dependencies

To install LXC software the EPEL CentOS Stream 9 repository must be installed. At present, the LXC included in CentOS Stream 9 EPEL repository is 4.0.

dnf install -y epel-release
dnf install -y lxc lxc-templates container-selinux
dnf install -y wget tar

lxc-templates uses template “download” to download different Linux distribution images from http://images.linuxcontainers.org/, which now redirects to http://uk.lxd.images.canonical.com/ (an Ubuntu lxd images mirror).
The container-selinux should be installed only if the host, i.e. the CentOS Stream 9 install, is with enabled SELinux. The packages offers additional SELinux rules or for the LXC and LXC tools like lxc-attach and more.

STEP 2) Create a Ubuntu 22.04 LTS with the help of LXC templates

[root@srv ~]# lxc-create --template download -n mycontainer -- --dist centos --release 9-Stream --arch amd64

In addition, there is a “–variant” option along with “--dist” and “--release” to specify which variant to install – default, cloud, desktop or other. There is a variant column in the table on the images’ page mentioned above.
Keep on reading!

Run LXC CentOS Stream 9 container with bridged network under CentOS Stream 9

In continue of the previous article with CentOS 8 – Run LXC CentOS 8 container with bridged network under CentOS 8, here is an updated version with CentOS Stream 9 running LXC container. In this case, the LXC container is CentOS Stream 9, too.
Under CentOS 8, the LXC software is from branch 3.x, but in CentOS Stream 9 the LXC is 4.x and there are some differences in the LXC configuration file.
It’s worth mentioning the differences between docker/podman containers and LXC from the previous article:

Multiprocesses.
Easy configuration modification. Even hot-plugin supported.
Unprivileged Linux containers.
Complex network setups. Multiple network interfaces connected to different networks, for example.
Live systemd, i.e. systemd or SysV init are booted as usual. Much of the software relies on systemd/udev features and in many cases, it is really hard to run software without a systemd or init process

Here are the steps to boot a CentOS Stream 9 container under CentOS Stream 9 host server:

STEP 1) Install EPEL repository.

EPEL CentOS Stream 9 repository now includes LXC 4.0 software.

dnf install -y epel-release

STEP 2) Install LXC software and start LXC service.

At present, the LXC software version is 4.0.12. The package lxc-templates includes template scripts to create a Linux distribution environment like CentOS, Ubuntu, Debian, Gentoo, ArchLinux, Oracle, Alpine, and many others and it also includes the configuration templates to start these Linux distributions. In fact, lxc-templates now includes a download script to download images from the Internet.

dnf install -y lxc lxc-templates container-selinux
dnf install -y wget tar

The wget and tar are required if LXC templates installation is going to be performed.
There is an additional package for container’s SELinux, which should be installed before starting the LXC service, because some of the SELinux rules may not apply in the system. If the SELinux is disabled the installation of container-selinux package might be skipped.

STEP 3) Create a CentOS Stream 9 container with the help of LXC templates and run it.

Use the lxc-templates to prepare a CentOS Stream 9 container environment. The currently available containers are listed here http://images.linuxcontainers.org/, which now redirects to http://uk.lxd.images.canonical.com/ (an Ubuntu lxd images mirror). Check out the URL and choose the right container. Here the CentOS Stream 9 amd64, i.e. release 9-Stream, is used.

[root@srv ~]# lxc-create --template download -n mycontainer -- --dist centos --release 9-Stream --arch amd64

MPEG-DASH and ClearKey, CENC drm encryption with Nginx, bento4 and dashjs under CentOS 8

The purpose of this article is to demonstrate a simple and plain example of ClearKey DRM encryption using a DASH stream.
Usually, the ClearKey is used only for testing the encryption key and the DRM setup, because the decrypting key is transferred in a plain text to the browser. In simple DRM words, the key is transferred in plain text, and the handle of the decryption is not in some proprietary module such as CMD – Content Decryption Modules. The CMD is a proprietary module in the browsers or the players, which works like a black box when handling the decryption key. The most popular DRMs are Google’s Widevine, Apple’s Fireplay, and Microsoft PlayReady, which work through a proprietary module – CMD (Content Decryption Modules) in the browser (or the OS and player).
All the three DRMs work basically in a similar way:

There is a (encryption) key and a (encryption) keyID, which purpose is to identify the (encryption) key.
The video file is encrypted with the key and it includes the keyID.
The client needs to have the appropriate CMD (Content Decryption Modules) to decrypt the video.
The clients receive a license from a license server, which is encrypted data for the CDM on how to decrypt the video identified by the keyID. In fact, the client sends the keyID and receives the proper license (i.e. license binary data) for this keyID. That’s why keyID is included in the encrypted video. Bare in mind, the CMD is proprietary Content Decryption Module offered by the creator of the DRM – Google, Apple, Microsoft or another and it lives in the browser (OS or player). All popular browsers support at least one of the proprietary DRMs.

ClearKey is like the proprietary DRM schemes, but without the CMD (Content Decryption Modules).

The “org.w3.clearkey” Key System uses plain-text clear (unencrypted) key(s) to decrypt the source. No additional client-side content protection is required.

So, in general, there is no need for a license server when using ClearKey DRM.
Of course, an additional attempt to hide the plain-text key could be made using an extension to the client’s player such as javascript modules and etc. In general, it is perceived this approach to be less secure, because it is much easier to debug the javascript code on the client side. More on ClearKey – https://www.w3.org/TR/encrypted-media/#clear-key

Here are all the steps from the server till the client to use ClearKey.

STEP 1) Download and install bento4 software.

bento4 is an open source toolkit for manipulating some of the most common video formats – MP4 and DASH/HLS/CMAF media. The download page is https://www.bento4.com/downloads/ and the Linux binary for latest stable version: https://www.bok.net/Bento4/binaries/Bento4-SDK-1-6-0-639.x86_64-unknown-linux.zip. There is also a source code snapshot link.
Download the famous blender video for the demostration: https://download.blender.org/demo/movies/BBB/bbb_sunflower_1080p_30fps_normal.mp4
Download and unpack the binary Bento4-SDK-1-6-0-639.x86_64-unknown-linux.zip.
Keep on reading!

Create bridge and add TUN/TAP device using NetworkManager nmcli under CentOS 8

This article shows how to create a network bridge device and a TUN/TAP device, which then is added to the bridge. The CentOS 8 Stream is used along with the console NetworkManager program nmcli.
TUN/TAP devices are often used in the virtualization world as a link device between the host machine and the virtual machine.

This article is for the case when the bridge does not include the main network interface (Internet network interface and so on) of the server but is an additional device, which MAC and virtual machine MACs would not be exposed through the server’s main network interface.

If the server’s main network interface should be included in the bridge device, i.e. replace the main network interface with the bridge there is another article on the subject – Replace current interface configuration with a bridge device using nmcli (NetworkManager)

Device name are as follow:

br0 is the name of the network bridge.
10.10.10.1 with mask /24 is the IP of the bridge device with name br0. Because the idea is to use the bridge only locally, a local interface is used. The IP is set manually.
tap0 is the name of TUN/TAP device.
enp0s3is the server’s main network connection. Not used in this howto.

Here are all the commands to create a bridge, create a TUN/TAP device and add it to the bridge, and then activate the bridge‘s link.

nmcli connection add type bridge ifname br0 con-name br0 ipv4.method manual ipv4.addresses "10.10.10.1/24"
nmcli con up br0
nmcli connection add type tun ifname tap0 con-name tap0 mode tap owner 0 ip4 0.0.0.0/24
nmcli con add type bridge-slave ifname tap0 master br0

Here are the steps with much more details and information including all the command output.
The networking before any reconfiguration:

[root@srv ~]# nmcli
enp0s3: connected to enp0s3
        "Intel 82540EM"
        ethernet (e1000), 08:00:27:03:C9:2E, hw, mtu 1500
        ip4 default
        inet4 192.168.0.20/24
        route4 192.168.0.0/24 metric 100
        route4 0.0.0.0/0 via 192.168.0.1 metric 100
        inet6 fe80::a00:27ff:fe03:c92e/64
        route6 fe80::/64 metric 100

lo: unmanaged
        "lo"
        loopback (unknown), 00:00:00:00:00:00, sw, mtu 65536

DNS configuration:
        servers: 8.8.8.8 1.1.1.1
        interface: enp0s3

Use "nmcli device show" to get complete information about known devices and
"nmcli connection show" to get an overview on active connection profiles.

Consult nmcli(1) and nmcli-examples(7) manual pages for complete usage details.
[root@srv ~]# nmcli con
NAME    UUID                                  TYPE      DEVICE 
enp0s3  09497bbf-da59-42b7-a72c-d69369760b36  ethernet  enp0s3

Keep on reading!

Run LXC CentOS 8 container with bridged network under CentOS 8

The LXC container software comes to CentOS 8 with the EPEL 8 repository. LXC is a multiprocesses container, which offers to boot a Linux distribution under container isolation. It is very similar to systemd-nspawn and a bit different from docker containers. LXC containers are used when multiple processes are needed under one container only. In most cases, the LXC container is a fully-featured Linux distribution (systemd or SysV, i.e. init) booted under a Linux container.
There are several major differences between docker/podman containers and LXC:

Multiprocesses.
Easy configuration modification. Even hot-plugin supported.
Unprivileged Linux containers.
Complex network setups. Multiple network interfaces connected to different networks, for example.
Live systemd, i.e. systemd or SysV init are booted as usual. Much of the software rellies on systemd/udev features and in many cases, it is really hard to run a software without a systemd or init process

Here are the steps to boot a CentOS 8 container under CentOS 8 host server:

STEP 1) Install EPEL repository.

EPEL CentOS 8 repository now includes LXC 3.0 software.

dnf install -y epel-release

STEP 2) Install LXC software and start LXC service.

At present, the LXC software version is 3.0.4. The package lxc-templates includes template scripts to create a Linux distribution environment like CentOS, Ubuntu, Debian, Gentoo, ArchLinux, Oracle, Alpine, and many others and it also includes the configuration templates to start these Linux distributions.

dnf install -y lxc lxc-templates
dnf install -y wget tar

The wget and tar are required if LXC templates installation is going to be performed.

STEP 3) Create a CentOS 8 container with the help of LXC templates and run it.

Use the lxc-templates to prepare a CentOS 8 container environment. The currently available containers are listed here http://images.linuxcontainers.org/. Check out the URL and choose the right container. Here the CentOS 8 amd64 is used.

lxc-create --template download -n mycontainer -- --dist centos --release 8 --arch amd64 --keyserver hkp://keyserver.ubuntu.com

Keep on reading!

Create and export a GlusterFS volume with NFS-Ganesha in CentOS 8

GlusterFS built-in NFS server supports only NFS version 3. GlusterFS offers NFS exports using NFS-Ganesha, which supports NFS version 3 and 4 protocols.
NFS-Ganesha server is a user-mode file sharing server, which offers a GlusterFS plugin to export GlusterFS volumes. In the following article, the NSF-Ganesha and GlusterFS are installed and a simple GlusterFS volume is created and then exported through NFS 3 and 4 version protocols.
The version of the software in this article:

CentOS Stream release 8 (25.04.2021)
GlusterFS 8.4
NFS-Ganesha 3.5

STEP 1) Install GlusterFS.

dnf install -y centos-release-gluster
dnf install -y glusterfs-server

The first line will installs a new repository under the SIG management – https://wiki.centos.org/SpecialInterestGroup/Storage. The second line installs the GlusterFS server.

STEP 2) Install NFS-Ganesha.

dnf install -y centos-release-nfs-ganesha30
dnf install -y nfs-ganesha nfs-ganesha-gluster

The first line again installs a new repository under the SIG management and the second line installs the NFS-Ganesha server with Gluster plugin.

STEP 3) Create GlusterFS volume

Start the GlusterFS server and create a simple 3 replicas volume with:
Start the GlusterFS on all the three nodes and enable the GlusterFS communication between the three nodes using firewall-cmd utility. So execute the following commands:

systemctl start glusterd
firewall-cmd --permanent --new-zone=glusternodes
firewall-cmd --permanent --zone=glusternodes --add-source=192.168.0.200
firewall-cmd --permanent --zone=glusternodes --add-source=192.168.0.201
firewall-cmd --permanent --zone=glusternodes --add-source=192.168.0.202
firewall-cmd --permanent --zone=glusternodes --add-service=glusterfs
firewall-cmd --reload

On the first node create the GlusterFS volume. First, add the glnode2 and glnode3 to the cluster.

gluster peer probe glnode2
gluster peer probe glnode3
gluster volume create VOL1 replica 3 transport tcp glnode1:/mnt/storage/gluster/brick glnode2:/mnt/storage/gluster/brick glnode3:/mnt/storage/gluster/brick
gluster volume start VOL1

Keep on reading!

CentOS 8.2 (RHEL 8.2) and above including CentOS Stream 9

STEP 1) Install additional repositories for Grafana, InfluxDB and collectd.

STEP 1) Install additional repositories for Grafana, influxdb and collectd.

STEP 1) Install, configure and start the database MariaDB.

STEP 1) Install the needed software EPEL repository and the LXC and its dependencies

STEP 2) Create a Ubuntu 22.04 LTS with the help of LXC templates

STEP 1) Install EPEL repository.

STEP 2) Install LXC software and start LXC service.

STEP 3) Create a CentOS Stream 9 container with the help of LXC templates and run it.

STEP 1) Download and install bento4 software.

STEP 1) Install EPEL repository.

STEP 2) Install LXC software and start LXC service.

STEP 3) Create a CentOS 8 container with the help of LXC templates and run it.

STEP 1) Install GlusterFS.

STEP 2) Install NFS-Ganesha.

STEP 3) Create GlusterFS volume