doc/app_netdata.md

## NetData

[NetData](http://my-netdata.io/) is a system for **distributed real-time performance and health monitoring**.
It provides **unparalleled insights, in real-time**, of everything happening on the
system it runs (including applications such as web and database servers), using
**modern interactive web dashboards**.

_netdata is **fast** and **efficient**, designed to permanently run on all systems
(**physical** & **virtual** servers, **containers**, **IoT** devices), without
disrupting their core function._

[![Install Piwigo with YunoHost](https://install-app.yunohost.org/install-with-yunohost.png)](https://install-app.yunohost.org/?app=piwigo)

**Customization brought by the package:**

* grant MySQL statistics access via a `netdata` user
* nginx root log statistics via putting `netdata` user in the `adm` group
* Dovecot statistics via giving access to Dovecot stats stocket to `netdata` user (works only with Dovecot 2.2.16+)

**Further recommendations:**
We don't allow YunoHost packages to make sensible changes to system files. So here are further customizations you can make to allow more monitoring:

* Nginx:
  * requests/connections: follow [these recommandations](https://github.com/firehol/netdata/tree/master/python.d#nginx) to enable `/stab_status` (for example by putting the `location` section in `/etc/nginx/conf.d/yunohost_admin.conf`
  * weblogs: you can monitor all your nginx weblogs for errors; follow [these recommendations](https://github.com/firehol/netdata/tree/master/python.d#nginx_log)
* phpfpm: follow [these recommandations](https://github.com/firehol/netdata/tree/master/python.d#phpfpm)

## Features

<p align="center">
<img src="https://cloud.githubusercontent.com/assets/2662304/19168687/f6a567be-8c19-11e6-8561-ce8d589e8346.gif"/>
</p>

 - **Stunning interactive bootstrap dashboards**<br/>
   mouse and touch friendly, in 2 themes: dark, light

 - **Amazingly fast**<br/>
   responds to all queries in less than 0.5 ms per metric,
   even on low-end hardware

 - **Highly efficient**<br/>
   collects thousands of metrics per server per second,
   with just 1% CPU utilization of a single core, a few MB of RAM and no disk I/O at all

 - **Sophisticated alarming**<br/>
   hundreds of alarms, **out of the box**!<br/>
   supports dynamic thresholds, hysteresis, alarm templates,
   multiple role-based notification methods (such as email, slack.com,
   pushover.net, pushbullet.com, telegram.org, twilio.com, messagebird.com)

 - **Extensible**<br/>
   you can monitor anything you can get a metric for,
   using its Plugin API (anything can be a netdata plugin,
   BASH, python, perl, node.js, java, Go, ruby, etc)

 - **Embeddable**<br/>
   it can run anywhere a Linux kernel runs (even IoT)
   and its charts can be embedded on your web pages too

 - **Customizable**<br/>
   custom dashboards can be built using simple HTML (no javascript necessary)

 - **Zero configuration**<br/>
   auto-detects everything, it can collect up to 5000 metrics
   per server out of the box

 - **Zero dependencies**<br/>
   it is even its own web server, for its static web files and its web API

 - **Zero maintenance**<br/>
   you just run it, it does the rest

 - **scales to infinity**<br/>
   requiring minimal central resources

 - **several operating modes**<br/>
   autonomous host monitoring, headless data collector, forwarding proxy, store and forward proxy, central multi-host monitoring, in all possible configurations.
   Each node may have different metrics retention policy and run with or without health monitoring.

 - **time-series back-ends supported**<br/>
   can archive its metrics on `graphite`, `opentsdb`, `prometheus`, json document DBs, in the same or lower detail
   (lower: to prevent it from congesting these servers due to the amount of data collected)

![netdata](https://cloud.githubusercontent.com/assets/2662304/14092712/93b039ea-f551-11e5-822c-beadbf2b2a2e.gif)

---

## What does it monitor?

netdata collects several thousands of metrics per device.
All these metrics are collected and visualized in real-time.

> _Almost all metrics are auto-detected, without any configuration._

This is a list of what it currently monitors:

- **CPU**<br/>
  usage, interrupts, softirqs, frequency, total and per core, CPU states

- **Memory**<br/>
  RAM, swap and kernel memory usage, KSM (Kernel Samepage Merging), NUMA

- **Disks**<br/>
  per disk: I/O, operations, backlog, utilization, space, software RAID (md)

   ![sda](https://cloud.githubusercontent.com/assets/2662304/14093195/c882bbf4-f554-11e5-8863-1788d643d2c0.gif)

- **Network interfaces**<br/>
  per interface: bandwidth, packets, errors, drops

   ![dsl0](https://cloud.githubusercontent.com/assets/2662304/14093128/4d566494-f554-11e5-8ee4-5392e0ac51f0.gif)

- **IPv4 networking**<br/>
  bandwidth, packets, errors, fragments,
  tcp: connections, packets, errors, handshake,
  udp: packets, errors,
  broadcast: bandwidth, packets,
  multicast: bandwidth, packets

- **IPv6 networking**<br/>
  bandwidth, packets, errors, fragments, ECT,
  udp: packets, errors,
  udplite: packets, errors,
  broadcast: bandwidth,
  multicast: bandwidth, packets,
  icmp: messages, errors, echos, router, neighbor, MLDv2, group membership,
  break down by type

- **Interprocess Communication - IPC**<br/>
  such as semaphores and semaphores arrays

- **netfilter / iptables Linux firewall**<br/>
  connections, connection tracker events, errors

- **Linux DDoS protection**<br/>
  SYNPROXY metrics

- **fping** latencies</br>
  for any number of hosts, showing latency, packets and packet loss

   ![image](https://cloud.githubusercontent.com/assets/2662304/20464811/9517d2b4-af57-11e6-8361-f6cc57541cd7.png)


- **Processes**<br/>
  running, blocked, forks, active

- **Entropy**<br/>
  random numbers pool, using in cryptography

- **NFS file servers and clients**<br/>
  NFS v2, v3, v4: I/O, cache, read ahead, RPC calls

- **Network QoS**<br/>
  the only tool that visualizes network `tc` classes in realtime

   ![qos-tc-classes](https://cloud.githubusercontent.com/assets/2662304/14093004/68966020-f553-11e5-98fe-ffee2086fafd.gif)

- **Linux Control Groups**<br/>
  containers: systemd, lxc, docker

- **Applications**<br/>
  by grouping the process tree and reporting CPU, memory, disk reads,
  disk writes, swap, threads, pipes, sockets - per group

   ![apps](https://cloud.githubusercontent.com/assets/2662304/14093565/67c4002c-f557-11e5-86bd-0154f5135def.gif)

- **Users and User Groups resource usage**<br/>
  by summarizing the process tree per user and group,
  reporting: CPU, memory, disk reads, disk writes, swap, threads, pipes, sockets

- **Apache and lighttpd web servers**<br/>
   `mod-status` (v2.2, v2.4) and cache log statistics, for multiple servers

- **Nginx web servers**<br/>
  `stub-status`, for multiple servers

- **Tomcat**<br/>
  accesses, threads, free memory, volume

- **web server log files**<br/>
  extracting in real-time, web server performance metrics and applying several health checks

- **mySQL databases**<br/>
  multiple servers, each showing: bandwidth, queries/s, handlers, locks, issues,
  tmp operations, connections, binlog metrics, threads, innodb metrics, and more

- **Postgres databases**<br/>
  multiple servers, each showing: per database statistics (connections, tuples
  read - written - returned, transactions, locks), backend processes, indexes,
  tables, write ahead, background writer and more

- **Redis databases**<br/>
  multiple servers, each showing: operations, hit rate, memory, keys, clients, slaves

- **mongodb**<br/>
  operations, clients, transactions, cursors, connections, asserts, locks, etc

- **memcached databases**<br/>
  multiple servers, each showing: bandwidth, connections, items

- **elasticsearch**<br/>
  search and index performance, latency, timings, cluster statistics, threads statistics, etc

- **ISC Bind name servers**<br/>
  multiple servers, each showing: clients, requests, queries, updates, failures and several per view metrics

- **NSD name servers**<br/>
  queries, zones, protocols, query types, transfers, etc.

- **Postfix email servers**<br/>
  message queue (entries, size)

- **exim email servers**<br/>
  message queue (emails queued)

- **Dovecot** POP3/IMAP servers<br/>

- **ISC dhcpd**<br/>
  pools utilization, leases, etc.

- **IPFS**<br/>
  bandwidth, peers

- **Squid proxy servers**<br/>
  multiple servers, each showing: clients bandwidth and requests, servers bandwidth and requests

- **HAproxy**<br/>
  bandwidth, sessions, backends, etc

- **varnish**<br/>
  threads, sessions, hits, objects, backends, etc

- **OpenVPN**<br/>
  status per tunnel

- **Hardware sensors**<br/>
  `lm_sensors` and `IPMI`: temperature, voltage, fans, power, humidity

- **NUT and APC UPSes**<br/>
  load, charge, battery voltage, temperature, utility metrics, output metrics

- **PHP-FPM**<br/>
  multiple instances, each reporting connections, requests, performance

- **hddtemp**<br/>
  disk temperatures

- **smartd**<br/>
  disk S.M.A.R.T. values

- **SNMP devices**<br/>
  can be monitored too (although you will need to configure these)

- **statsd**<br/>
  [netdata is a fully featured statsd server](https://github.com/firehol/netdata/wiki/statsd)

And you can extend it, by writing plugins that collect data from any source, using any computer language.

## Links

 * Report a bug: https://github.com/YunoHost-Apps/netdata_ynh/issues
 * NetData website: http://my-netdata.io/

 -----------------------------

 # <img src="/images/APPLICATION_logo.svg" width="80px" alt="APPLICATION's logo"> APPLICATION

 [![Install APPLICATION with YunoHost](https://install-app.yunohost.org/install-with-yunohost.png)](https://install-app.yunohost.org/?app=APPLICATION) [![Integration level](https://dash.yunohost.org/integration/APPLICATION.svg)](https://dash.yunohost.org/appci/app/APPLICATION)

 - [Configuration](#Configuration)
 - [Limitations with YunoHost](#limitations-with-yunohost)
 - [Customer Applications](#Customer-applications)
 - [Useful links](#useful-links)

 **General presentation of the application.** *Lorem ipsum dolor sit amet, consectetur adipiscing elit. Fusce rutrum sodales mauris eu viverra. Sed dapibus, tellus sit amet interdum condimentum, enim eros faucibus ligula, sed suscipit orci velit at felis. Etiam quam lacus, vulputate eu scelerisque ac, sollicitudin rutrum orci. Cras eu ante porttitor, laoreet odio sed, hendrerit tellus. Nulla luctus sem in arcu scelerisque cursus. Nulla ut tellus at leo porttitor tincidunt. Morbi vitae purus convallis, elementum lectus non, dignissim orci. Integer eget egestas mauris. Nunc nunc dolor, cursus in quam mollis, rutrum fermentum nibh. Aliquam molestie velit a nulla porttitor, sit amet tincidunt erat laoreet.*

 ## Configuration

 **If the configuration of the application is not done with the admin panel of YunoHost.** *Lorem ipsum dolor sit amet, consectetur adipiscing elit. Fusce rutrum sodales mauris eu viverra. Sed dapibus, tellus sit amet interdum condimentum, enim eros faucibus ligula, sed suscipit orci velit at felis. Etiam quam lacus, vulputate eu scelerisque ac, sollicitudin rutrum orci. Cras eu ante porttitor, laoreet odio sed, hendrerit tellus. Nulla luctus sem in arcu scelerisque cursus. Nulla ut tellus at leo porttitor tincidunt. Morbi vitae purus convallis, elementum lectus non, dignissim orci. Integer eget egestas mauris. Nunc nunc dolor, cursus in quam mollis, rutrum fermentum nibh. Aliquam molestie velit a nulla porttitor, sit amet tincidunt erat laoreet.*

 ## Limitations with YunoHost

 **Explanation of the current limitations in using the application with YunoHost.** *Lorem ipsum dolor sit amet, consectetur adipiscing elit. Fusce rutrum sodales mauris eu viverra. Sed dapibus, tellus sit amet interdum condimentum, enim eros faucibus ligula, sed suscipit orci velit at felis. Etiam quam lacus, vulputate eu scelerisque ac, sollicitudin rutrum orci. Cras eu ante porttitor, laoreet odio sed, hendrerit tellus. Nulla luctus sem in arcu scelerisque cursus. Nulla ut tellus at leo porttitor tincidunt. Morbi vitae purus convallis, elementum lectus non, dignissim orci. Integer eget egestas mauris. Nunc nunc dolor, cursus in quam mollis, rutrum fermentum nibh. Aliquam molestie velit a nulla porttitor, sit amet tincidunt erat laoreet.*

 ## Customer applications

 | Application name | Platform | Multi-account | Other supported networks | Play Store | F-Droid | Apple Store | *Other* |
 |------------------|----------|---------------|--------------------------|------------|---------|-------------|---------|
 |                  |          |               |                          |            |         |             |         |

 ## Useful links

 + Website: [WEBSITE](#)
 + Official documentation: [DOCUMENTATION](#)
 + Application software repository: [github.com - YunoHost-Apps/APPLICATION](https://github.com/YunoHost-Apps/APPLICATION_ynh)
 + Fix a bug or an improvement by creating a ticket (issue): [github.com - YunoHost-Apps/APPLICATION/issues](https://github.com/YunoHost-Apps/APPLICATION_ynh/issues)