The mantra of the real estate world is Location, Location, Location. For the world of system administration, this sacred text should sound like this: Visibility, Visibility and once again Visibility. If you don't know exactly what your network and servers are doing every second of the day, you're like a pilot flying blind. A catastrophe awaits you. Lucky for you, there are a lot of good programs available on the market, both commercial and open source, that can do your network monitoring.

Since good and free is always more tempting than good and expensive, here is a list of open source programs that prove their worth every day in networks of any size. From discovering devices, monitoring network equipment and servers, to identifying network trends, graphing monitoring results, and even backing up switch and router configurations, these seven free utilities are likely to surprise you.

Cacti

First there was MRTG (Multi Router Traffic Grapher) - a program for organizing a network monitoring service and measuring data over time. Back in the 1990s, its author Tobias Oetiker saw fit to write a simple graphing tool using a ring database, originally used to display the throughput of a router on a LAN. So MRTG gave birth to RRDTool, a set of utilities for working with RRD (Round-robin Database, ring database), which allows you to store, process and graphically display dynamic information such as network traffic, processor load, temperature, and so on. Now RRDTool is used in a huge number of open source tools. Cacti is the modern flagship of open source network graphics software and takes the principles of MRTG to a whole new level.

From disk usage to power supply fan speed, if it can be tracked,Cacti will be able to display it and make this data easily accessible.

Cacti is a free program included in the LAMP suite of server software that provides a standardized software platform for plotting virtually any statistical data. If any device or service returns numeric data, then they can most likely be integrated into Cacti. There are templates for monitoring a wide range of equipment, from Linux and Windows servers to Cisco routers and switches, basically anything that talks on SNMP (Simple Network Management Protocol). There are also collections of third-party templates that further expand the already huge list of Cacti-compatible hardware and software.

While Cacti's standard data collection method is SNMP, Perl or PHP scripts can also be used. The software system framework cleverly separates data acquisition and graphical display into discrete instances, making it easy to reprocess and reorganize existing data for different visual representations. In addition, you can select specific time frames and parts of the charts by simply clicking and dragging them.

So, for example, you can quickly look at data from several years ago to see if the current behavior of the network equipment or server is anomalous, or if such indicators appear regularly. And with Network Weathermap, a PHP plugin for Cacti, you can effortlessly create real-time maps of your network showing the traffic between network devices using graphs that appear when you hover your mouse over a network channel image. Many organizations using Cacti display these maps on 42-inch wall-mounted LCD monitors 24/7, allowing IT to instantly monitor network traffic and link status.

In summary, Cacti is a powerful graphing and trending network performance toolkit that can be used to monitor virtually any monitored metric that can be graphed. The solution also supports almost limitless customization options, which can make it overly complex for certain applications.

Nagios

Nagios is an established network monitoring software system that has been in active development for many years. Written in C, it allows you to do almost everything that system and network administrators might need from a monitoring application package. The web interface of this program is fast and intuitive, while its back-end is extremely reliable.

Nagios can be a problem for beginners, but the rather complex configuration is also an advantage of this tool, as it can be adapted to almost any monitoring task.

Like Cacti, there is a very active community supporting Nagios, so various plugins exist for a huge variety of hardware and software. From simple ping checks to integration with complex software solutions, such as WebInject, a free Perl-based web application and service testing tool. Nagios allows you to constantly monitor the status of servers, services, network links and everything else that understands the IP network layer protocol. For example, you can monitor server disk space usage, RAM and CPU usage, FLEXlm license usage, server outlet air temperature, WAN and Internet latency, and more.

Obviously, any server and network monitoring system will not be complete without notifications. Nagios is fine with that: the software platform offers a customizable email, SMS, and instant messaging notification mechanism for most popular Internet messengers, as well as an escalation scheme that can be used to make intelligent decisions about who, how and when. what circumstances should be notified that with the right settings will help you ensure many hours of restful sleep. And the web interface can be used to temporarily suspend receiving notifications or acknowledging a problem that has occurred, as well as making notes by administrators.

In addition, the display feature shows all monitored devices in a logical, color-coded representation of their location on the network, allowing problems to be shown as they occur.

The disadvantage of Nagios is the configuration, as it is best done through the command line, which makes it much more difficult for beginners to learn. Although people who are familiar with the standard Linux/Unix configuration files should not have much trouble.

The possibilities of Nagios are huge, but the effort to use some of them may not always be worth the effort. But don't let the complexity intimidate you: the early warning benefits that this tool provides for so many aspects of the network cannot be overestimated.

Icinga

Icinga started as a fork of the Nagios monitoring system, but has recently been rewritten into a standalone solution known as Icinga 2. Both versions of the program are currently in active development and available for use, while Icinga 1.x is compatible with a large number of plugins and configuration Nagios. Icinga 2 was designed to be less bulky, performance oriented, and more user friendly. It offers a modular architecture and multi-threaded design that neither Nagios nor Icinga 1 has.

Icinga offers a complete monitoring and alerting software platform that is designed to be as open and extensible asNagios, but with some differences in the web interface.

Like Nagios, Icinga can be used to monitor anything that speaks the IP language, as deep as you can with SNMP, as well as custom plugins and add-ons.

There are several variations of the web interface for Icinga, but the main difference between this monitoring software solution and Nagios is the configuration that can be done through the web interface rather than through configuration files. For those who prefer to manage their configuration outside of the command line, this functionality will be a real boon.

Icinga integrates with a variety of monitoring and graphical display software packages such as PNP4Nagios, inGraph and Graphite to provide a robust visualization of your network. In addition, Icinga has advanced reporting capabilities.

NeDi

If you've ever had to Telnet to switches to find devices on your network and search by MAC address, or you just want to be able to determine the physical location of certain equipment (or perhaps even more it doesn't matter where it was located before), then it will be interesting for you to take a look at NeDi.

NeDi constantly scans the network infrastructure and catalogs devices, keeping track of everything it finds.

NeDi is a free software related to LAMP that routinely scans the MAC addresses and ARP tables on the switches in your network, cataloging each discovered device in a local database. This project is not as well known as some others, but it can be a very handy tool when dealing with corporate networks where devices are constantly changing and moving.

You can use the NeDi web interface to search for a switch, switch port, access point, or any other device by MAC address, IP address, or DNS name. NeDi collects all the information it can from every network device it encounters, pulling serial numbers, firmware and software versions, current times, module configurations, and more. You can even use NeDi to mark MAC- addresses of devices that have been lost or stolen. If they appear online again, NeDi will let you know.

Discovery is triggered by a cron process at specified intervals. The configuration is simple, with a single configuration file that allows for much more customization, including the ability to skip devices based on regular expressions or set network boundaries. NeDi typically uses the Cisco Discovery Protocol or Link Layer Discovery Protocol to discover new switches and routers and then connects to them to collect their information. Once the initial configuration is set, device discovery will be pretty fast.

Up to a certain level, NeDi can integrate with Cacti, so it is possible to link device discovery to the corresponding Cacti graphs.

Ntop

The Ntop project - now better known to the "new generation" as Ntopng - has come a long way in the last decade. But call it what you want - Ntop or Ntopng - as a result, you get a first-class tool for monitoring network traffic paired with a fast and simple web interface. It is written in C and is completely self contained. You start a single process configured on a specific network interface, and that's all it needs.

Ntop is a lightweight web-based packet sniffing tool that shows you real-time network traffic data. Information about the data flow through the host and about the connection to the host is also available in real time.

Ntop provides easy-to-digest graphs and tables showing current and past network traffic, including protocol, source, destination, and history of specific transactions, as well as hosts at both ends. In addition, you'll find an impressive array of graphs, charts, and real-time network usage maps, as well as a modular architecture for a huge number of add-ons, such as adding NetFlow and sFlow monitors. Here you can even find Nbox - a hardware monitor that embeds in Ntop.

In addition, Ntop includes an API for the Lua scripting programming language that can be used to support extensions. Ntop can also store host data in RRD files for ongoing data collection.

One of the most useful uses of Ntopng is to control traffic to a specific location. For example, when some of the network links are highlighted in red on your network map, but you don't know why, you can use Ntopng to get a minute-by-minute report on the problematic network segment and immediately find out which hosts are responsible for the problem.

The benefit of such network visibility is difficult to overestimate, and it is very easy to get it. Essentially, you can run Ntopng on any interface that has been configured at the switch level to monitor a different port or VLAN. That's all.

Zabbix

Zabbix is ​​a full-blown network and system monitoring tool that combines several functions in one web console. It can be configured to monitor and collect data from a wide variety of servers and network devices, maintaining and monitoring the performance of each site.

Zabbix allows you to monitor servers and networks using a wide range of tools, including monitoring of virtualization hypervisors and web application stacks.

Basically, Zabbix works with software agents running on monitored systems. But this solution can also work without agents, using the SNMP protocol or other monitoring capabilities. Zabbix supports VMware and other virtualization hypervisors by providing detailed hypervisor performance and activity data. Particular attention is also paid to the monitoring of Java application servers, web services and databases.

Hosts can be added manually or through an automatic discovery process. A wide range of default templates apply to the most common use cases such as Linux, FreeBSD and Windows servers; widely used services such as SMTP and HTTP as well as ICMP and IPMI for detailed network hardware monitoring. In addition, custom checks written in Perl, Python or almost any other language can be integrated into Zabbix.

Zabbix allows you to customize your dashboards and web interface to focus on the most important network components. Notifications and problem escalations can be based on custom actions that are applied to hosts or groups of hosts. Actions can even be configured to run remote commands, so some script of yours can run on a controlled host if certain event criteria are observed.

The program graphs performance data such as network bandwidth and CPU usage and collects it for custom display systems. In addition, Zabbix supports customizable maps, screens, and even slideshows showing the current status of monitored devices.

Zabbix can be difficult to implement initially, but judicious use of auto-discovery and various patterns can alleviate some of the integration difficulties. In addition to being an installable package, Zabbix is ​​available as a virtual appliance for several popular hypervisors.

observium

Observium is a network equipment and server monitoring software that has a huge list of supported devices using the SNMP protocol. As a LAMP related software, Observium is relatively easy to install and configure, requiring the usual Apache, PHP and MySQL installations, database creation, Apache configuration, and the like. It installs as its own server with a dedicated URL.

Observium combines system and network monitoring with performance trending. It can be configured to track almost any metric.

You can enter the GUI and start adding hosts and networks, as well as set up auto-discovery ranges and SNMP data so that Observium can explore the networks around it and collect data on each discovered system. Observium can also discover network devices via CDP, LLDP or FDP protocols, and remote host agents can be deployed on Linux systems to help with data collection.

All of this collected information is available through an easy-to-use user interface that provides advanced statistical display options as well as charts and graphs. You can get anything from ping and SNMP response times to throughput graphs, fragmentation, IP packet counts, and more. Depending on the device, this data can be available up to every discovered port.

As for servers, for them Observium can display information about the state of the central processor, RAM, data storage, swap, temperature, etc. from the event log. You can also enable data collection and performance graphing for various services including Apache, MySQL, BIND, Memcached, Postfix, and more.

Observium works great as a virtual machine, so it can quickly become the go-to tool for getting information about the status of servers and networks. This is a great way to add auto-discovery and graphical representation to any size network.

Too often, IT administrators feel they are limited in what they can do. Whether we're dealing with a custom software application or an "unsupported" piece of hardware, many of us feel that if the monitoring system can't handle it right away, it's impossible to get the data we need in that situation. This, of course, is not true. With a little effort, you can make almost everything more visible, accounted for, and controlled.

An example is a user application with a database on the server side, for example, an online store. Your management wants to see beautiful graphs and charts, designed in one form or another. If you are already using, say, Cacti, you have several options to display the collected data in the required format. You can, for example, write a simple Perl or PHP script to run queries against the database and pass those calculations to Cacti, or you can SNMP call the database server using a private MIB (Management Information Base). One way or another, but the task can be done, and done easily, if you have the necessary tools for this.

Most of the free network monitoring utilities listed in this article should not be difficult to access. They have bundled versions available for download for the most popular Linux distributions, unless they are originally included. In some cases, they may be pre-configured as a virtual server. Depending on the size of your infrastructure, configuring and configuring these tools can be quite time-consuming, but once they're up and running, they'll be a solid foundation for you. As a last resort, it is worth at least testing them.

Regardless of which of these above systems you use to keep an eye on your infrastructure and equipment, it will provide you with at least the functionality of another system administrator. Although it cannot fix anything, it will monitor literally everything on your network around the clock, seven days a week. The time spent on installation and configuration will pay off with a vengeance. Also, be sure to run a small set of standalone monitors on another server to observe the main monitor. This is the case when it is always better to keep an eye on the observer.

Always in touch, Igor Panov.

While browsing the Internet, the user sometimes has problems: connection is lost, pages open slowly, etc. How does this happen? What to do in such situations to avoid repetition?

The reasons for which the poor quality of the Internet connection appears, we will unite in groups:

• Provider tariff.

Internet speed for the end user is provided by the ISP. Each service package has a speed limit. For example, Dom.Ru provides the following tariff plans:

For comparison: viewing of medium quality video is available in the first versions, and for UltraHD 4K you will need higher-speed connections.

• ISP network equipment.

On the side of the service provider, there is specialized network equipment that provides customers with access to the Internet. In the evening, the maximum number of simultaneous connections occurs, which leads to a drop in speed for the end user. The problem is solved only by the telecom operator: it is necessary to buy new routers and distribute the load.

How Poor Internet Connection Quality Affects Internet Speed

Let's consider how the speed indicator on the Internet changes with a low signal quality. The user opens a browser, enters an address and goes to the site.

If there are violations in the data lines, the page takes a long time to load or does not open, giving a 404 (page not found) error.

Another option: the page opens, but intermittently. That is, the data is being loaded, and then the connection is interrupted. The channel is restored after a minute, but the items are displayed with errors.

Let's take a closer look at how the Internet is checked for signal stability and correct the situation in case of problems.

How to check the quality of the Internet connection on a computer or phone

Quality (stability) and speed of connection to the World Wide Web are different concepts. Accordingly, testing methods are different.

Here are typical ways to check the quality of the Internet signal for mobile devices and personal computers.

On PC

The simplest way is to run the ping command with unlimited time. Press Win + R, type cmd.

A new workspace will open. We write ping -t 8.8.8.8

The syntax is decoded as follows:

1. PING is the name of the utility.
2. –t – launch key, in which the utility accesses a certain IP address an infinite number of times.
3. 8.8.8.8 is Google's public DNS server.

The command constantly sends the simplest requests to the server, and an acknowledgment comes in response. If the signal quality is poor, some packets will be lost. In the screenshot, the example is highlighted in red.

Important! Since ping is running as a continuous process, you can interrupt it with the keyboard shortcut Ctrl + C.

The second point, which we definitely pay attention to, is the minimum and maximum time for sending / receiving packets. If the difference is large, this also indicates poor channel quality.

As an alternative, consider the WinMTR utility.

Download the archive, unpack, run the software.

In the Host line, specify the IP address of the server that will receive requests. Let's take the well-known address 8.8.8.8 as an example. Next, click Start.

To stop the process, click the Stop button. The utility unloads the received information in text format or HTML text. If the channel quality is good, the ping will be low.

On a mobile device

For mobile platforms, there are applications available for download in online stores. For example, SpeedTest. Link:

• Play Market: https://play.google.com/store/apps/details?id=org.zwanoo.android.speedtest

Download the application, click "Start".

The utility is a combined solution that will also test the incoming and outgoing speeds.

Red highlighted items that show the stability of the signal: ping and packet loss. If there are problems with the channel, the first value is expressed as a three-digit number, and the loss is displayed as a percentage.

There are many solutions for Android and iOS phones, but the function is the same - running the ping command to check the stability of the Internet connection.

Also, the signal quality drops if the connection level is weak. Let's say the user is in a village where there is one tower for the next 50 kilometers. Its capabilities are not enough for subscribers within range.

How to Fix Poor Internet Connection Quality

Let's figure out how to "fix" the Internet, that is, correct the situation. First, we test the speed that is available to the user and the quality of the connection.

Important! The signal must be resistant to interference and work without "breaks"

To do this, open the SpeedTest application, which was described above.

Speed ​​indicators are highlighted in red. If the values ​​do not correspond to those declared by the provider, and the indicator of the ping utility becomes three-digit, we contact the operator's technical support.

The link quality test is also called the Internet Break Test. This is because the unstable signal is interrupted (a “break” occurs), resulting in data loss.

Features of the Wi-Fi router

The second key point is the router: it is necessary to check the operability of the network equipment on the end user's side. We connect to it with another smartphone or laptop and check it.

If the Internet is still unavailable or “lags” (pages “slow down” while opening), the problem is on the side of the network equipment. We reboot the router, check the access to the Internet.

We also update the router firmware, as the vendor releases updates regularly. We go to the developer's website, search for the model by name, download the current version of the firmware.

Open the device settings, find the tab "Update" (Update). Specify the path to the downloaded update and start the process. After installing the "fresh" version of the software, the router must be rebooted.

Important! The account name, password and configuration are stored by the provider.

Instructions for configuring the router, depending on the model, are on the website in the “Router Settings” section.

Incorrect network settings

The third node is the end device of the consumer: let's check the network parameters of the PC and smartphone.

1. In the lower right corner of the monitor, right-click the manipulator on the Network icon, activate the "Network Settings" item.
2. At the bottom of the window, select the option marked in red in the image.
3. Click on the Ethernet item on the right side.
4. Next, click the "Properties" button.
5. Select the line by double-clicking with the left mouse button, marked in the screenshot with a blue highlight.
6. In the window that opens, check the value of the lines: IP address and DNS server. By default, the value is automatic.

Important! Before changing network settings, you need to check with your service provider for the correct settings.

7. We also check the firewall settings, which blocks Internet connections in the "online" mode.
   
8. Open the application settings and disable protection. We check access to sites. If everything works, then we edit the firewall security policy.
   

Conclusion

The publication considered the main factors that affect the quality of communication. It is considered how to check the Internet for connection stability depending on the type of equipment used, as well as ways to solve problems.

Agree that it just infuriates when pages load for 3-5 minutes, photos and videos do not open at all, and uploading the next portion of your favorite series takes several hours! At the same time, the provider responds to all indignant exclamations: “We are fine. The speed is within the normal range.

How to be in a similar situation? It's simple: there are many ways to check the speed of the Internet and get objective data about your connection to the Web. And then - either present them to your provider and demand the provision of a quality service, or simply change it to another.

What is internet speed?

First of all, this is the period of time during which data is transferred from your computer to the Network or vice versa. Accordingly, there are two types of speed:

• incoming - reception speed (loading pages in the browser, files from the mailbox, online games, videos, photos, and so on);
• outgoing - upload speed (sending files, photos, videos or uploading them to websites, social networks).

The unit of speed measurement is megabit per second or abbreviated as Mb / s, where the letter “b” is small. On most torrents, it is measured in megabytes per second (MB / s, where the letter "B" is capital). 1 MB = 8 MB.

How much to weigh in grams? What does a specific indicator mean?

Considering the offers of providers, you need to at least roughly imagine what exactly you will get when you connect an Internet channel of a certain bandwidth.

Keep in mind that the speed of reception and return is a variable value. It can change significantly during the day. Therefore, most providers indicate in the contract not a specific range, but a vague phrase: “up to X Mb / s”.

What other indicators characterize the quality of the Internet connection?

In addition to speed, you can also evaluate an indicator called Ping - this is the server response time, measured in milliseconds. The smaller it is, the better the connection. This parameter is especially important for those who play online games or even participate in online battles. A fast server response in this case will mean no delays in the game. The lower the Ping value, the better:

There is also such an indicator as jitter - it displays fluctuations in the Ping value (also in milliseconds) and demonstrates the stability of the connection. The lower the jitter value, the better.

Services for checking speed

What you need to watch - figured out. Now let's explore several convenient services where you can quickly and efficiently check the key indicators of your Internet connection.

To get the most accurate results, you need to disable all applications on your computer or smartphone: torrents, radio, games, antivirus programs. Ideally, when checking, the computer should be directly connected to the Network, and not through a router (its settings may limit the flow of transmitted data).

Testing is best done 2-3 times and take into account the average measurement result.

fast.com

Fans of minimalism are encouraged to use the American web tool from Netflix. When you click on the link, the Internet speed detection is automatically launched and in just a few seconds the test result will be ready:

True, it is not very clear what kind of speed it determines: incoming or outgoing? Or some kind of middle ground? Judging by the measurements on other sites, it is the incoming connection that is being tested.

Here, too, everything is very simple and functional. Follow the link and click on the "Measure" button:

Shows only the incoming and outgoing connection speed. Here's an example:

According to user reviews, the service slightly exaggerates the results. In addition to speed, it also determines the IP address, browser type, screen resolution and your location.

speedmeter.de

This is a German development that responds to pressing the "Forward" button. According to user reviews, it is highly reliable and allows you to measure the quality of 4G connections. My results are below: