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Month: October 2021

DNS Record Types Cheat Sheet

In case you are just starting managing your DNS, these DNS record types are fundamental. So, let’s explain a little bit more about them.

SOA record

The acronym SOA stands for Start Of Authority, and it is essential to explain this record first. With it, you can show the origin of the authority DNS zone. This DNS record holds inside very important information about the DNS zone. It is a must-have if you want your DNS network to operate normally. The SOA record points to the primary DNS server. In addition, it stores information for the domain administrator and contact information. It also includes parameters such as the domain serial number and how often it should refresh. It is important to note that there should be just one SOA record for a particular DNS zone.

A and AAAA record

The A record is probably the most well-known of all DNS record types. The reason for that is simple, and it is in use in nearly every DNS system. The purpose of the A (address) record is to map a domain name to its corresponding IP address. Thanks to it, people are not obliged to memorize long and challenging numbers. However, the A record is applicable only when it comes to IPv4 addresses.

On the other hand, the AAAA record comes in handy when we want to map a domain name to an IPv6 address. However, compared to the A record, it is not so frequently used. With increasing the number of devices worldwide, eventually, the IPv6 address and the AAAA record are going to get more popular. 

MX record

The MX (Mail Exchanger) record is another one of the common and essential DNS record types. With it, you are able to point the email server responsible for receiving emails for your domain. It includes the domain name, which points to the hostname of the incoming mail server. Remember, it has to point to a hostname, not an IP address.

It is possible to set several MX records with different priorities and establish a backup in case of some difficulties. This DNS record type is crucial for you if you want to receive emails. 

CNAME record

The CNAME record indicates the actual, canonical domain name for the domain or subdomain. A popular way of implementing this DNS record type is for subdomains. That way, the administration of your DNS becomes easier. You only have to make a CNAME record for each of your subdomains and point it to the domain name. Then, every time you make any modifications to your domain, you don’t have to update the changes over for each subdomain.

PTR record

The PTR record is another fundamental DNS record, which is oftentimes called pointer record. It performs quite the opposite to the A record and it is used for backchecks. It points an IP address (IPv4 or IPv6) to a hostname. It is necessary because the rest of the servers worldwide might require proving that an IP address actually relates to a hostname before accepting a service, involving in communication, or some other action. Therefore, it is principally used a lot in the verification of the host.

7 tactics to protect against DDoS attacks in 2021.

Statistics of cyber attacks are multiplying fast every year. Online businesses really have to strengthen their security in 2021 to prevent or mitigate these threats. Don’t wait any longer! Enable today the necessary these 7 tactics to protect your business against DDoS attacks.

Know what a DDoS attack is.

A distributed denial of service (DDoS) is an attack where criminals look to drown a victim (network or server) by sending it massive traffic loads from multiple sources (infected devices). 

There are different types of DDoS, and each uses a specific technique to produce the traffic. But generally, criminals send a massive amount of requests to their victim to shut it down and get the denial of service for legit users.

Let’s get deeper into the threat and its techniques to build an efficient strategy against it.

Monitor your network’s traffic.

Online businesses have traffic patterns. You must understand them to distinguish normal traffic from abnormal. Constant monitoring can point sudden spikes or strange activity. Knowing your traffic, plus a smart monitor will help you catch the first DDoS symptoms before it is too late.

Add bandwidth.

Especially talking about large-scale volumetric DDoS, to increase bandwidth means the chance for making your highway wider to handle the traffic. Bandwidth itself won’t stop an attack, but it can make it possible to handle if detected at an early stage.

Get a load balance solution.

A load balance solution efficiently distributes big traffic loads. It directs them from one server to another to balance their workload and to prevent them from stress or the exhaustion of their resources. 

Get a CDN solution.

A content distribution network (CDN) is a network of web hosting servers distributed in different points of the world. Due to the amount and different location of its servers, they back each other up. If a server suffers an attack, traffic can be directed to another, keeping your online business available for users. 

Besides, CDN providers include in their plans security features to protect you. If you need extra protection, they usually supply this in their more robust plans. 

Get security and anti-DDoS technology. 

Building efficient defenses against DDoS attacks requires modern technology. It can’t sort it out with a single tool. You need multi-level protection. Monitoring tools, firewalls, load balancer, filters, and more to prevent intrusions in your system, to detect malicious activity before it harms.

Some anti-DDoS solutions can be outsourced for the convenience of your pocket. There are plans in which you can scale resources up or down based on your real needs. 

Keep good practices and quality maintenance.

Prevention of risks is a daily practice. Your employees must take security seriously. The importance of passwords and authentication processes, risks of phishing, etc. Close the gaps human errors leave for criminals to take advantage of.

Scan and run tests to detect failures in your system that can become weak spots for criminals to intrude. Updating will help you to patch on time possible holes in your software. 

Design a response plan. 

Response time is a critical factor in stopping a DDoS, reducing damages, or being devastated by it. Steps to face the emergency must be defined in advance to react accurately and fast – people in charge, how to prioritize the system’s resources, who to warn, etc. 

Conclusion. 

DDoS attacks are a dangerous reality. There are tactics to be protected and to fight back if needed. Not to be prepared in advance, it’s like playing with fire!  

How to use the Traceroute command to diagnose IP routing problems?

Among the many commands you have built-in in your operating system (OS), there is one that helps you see each point of the path of the data packets from your device to its destination, and it is called the Traceroute command. It is a useful diagnostic tool for checking IP routing problems.

​What is the Traceroute command?

The Traceroute command is software with a command-line interface, and you can use it to troubleshoot network problems. You can use it for these specific purposes: 

  • To see the complete route of data packets from your device to the target that you have chosen. That will open your eyes to each router/hop that the packets pass through. 
  • To see the time it takes for a complete route from your device to the target. You could see if it is within the norms. 
  • Identify the devices that your packets pass through. Most of them will be visible with their IP address and hostname. 
  • To find the bottleneck. You can see a particular hop that is responding too slow, or it is not responding at all. The Traceroute command can serve you to show you this problematic spot. That step could have a problem that you can further check by other tools.

​Understanding the Traceroute command

The Traceroute command has the following syntax:

traceroute [options] host_Address [pathlength] (Linux)

1. First, you start with the name of the command that you want to use. In our case, it is the “traceroute”.

2. Second, we can add an option for a more specific query. You have many choices like using IPv6, use another protocol for the data packets, change the waiting period, change the total number of packets sent, forbid fragmentation, maximum hops, and more. You can see the whole list of options with the following command, written inside the Terminal:

traceroute -help

3. The third will be the target of your query. You can use a hostname like your site’s domain name, or you can use an IP address like the address of your server.

​How to use the Traceroute command and to read the results

So, let’s just trace the route to Google.com

traceroute google.com

What you will see is an answer that is devised in a few columns. The first will show the hops it takes to reach the target. The second will show the IP addresses of those hops. And the last part will show each of the ping messages that the traceroute have sent, with the time they took. 

Now you have a good picture of all the hops that the query takes. You can see if there are any particular delays on the route, and you know between which two devices the problem is occurring. 

​Problems with the Traceroute command that you could experience. 

Sometimes you could have some problems with the command and have some data missing. 

​Request timed out.

This message could appear because: 

  • the target that you are checking is down and can’t respond. 
  • The command is disabled on a gateway.
  • The firewall is blocking the request. 
  • A connection problem. 

​An asterisk sign (*) in the result. 

  • A packet has been lost.
  • The particular router is discarding the packet on purpose. 

​Abnormal round trip time.

You can see an abnormal round trip time between different hops, where there is a very low number on one and higher on another. Repeat the command a few times to see if these numbers are consistent. The routers treat the ping messages as a low-priority process, and sometimes they process it later. This might be the reason. You can investigate further to see what the problem is. 

​Ping command basics for testing your network

The ping command might seams too basic for many people, but it is still around, and there is a reason for that. It is one of the fastest and easiest ways to find out if a particular device is connected. Just ping it, and in a matter of moments, you will see a clear answer. 

​What is the Ping command? 

The Ping command is a command that you can find on various Oses, including Windows, Linux, macOS, FreeBSD, and more. It serves to check if there is a direct connection between your device (the origin of the command) and the target (the IP address or domain name of the one you want to check). It uses Internet Control Message Protocol (ICMP) packets that it sends to the target. The target should receive them and answer back with echo messages. The echo message travels back to the origin and shows a statistic that includes the time it took to reach the target and if there were any lost packets. 

​How to use it? 

On Windows devices, there are two ways to use the Ping command – through the Command Prompt or through the Windows PowerShell. 

On macOS and Linux, you can use it through the Terminal application. 

​What can you test with the Ping command? 

  • See if a particular device like your server is connected at the moment. If it is reachable, that means there is a connection between you and the target.
  • See if the target responds fast enough. You can check the target on a regular basis and write it down. If the target responds slower than usual, there might be a problem that you can further explore. 
  • You can check different parts of the network and see if there is a bottleneck. 
  • Keep the Ping command constantly on so you can monitor the target constantly. This can be used with your server so you can be sure it is working normally. 

​Examples of the Ping command

No matter the OS and the Software you are using (Command Prompt, Terminal, etc.), you can ping a target using their domain name or their IP address. 

ping www.google.com

ping 172.217.169.142

​How to get additional options for the Ping command? 

There are many more options that you can use with this command. You can adjust the number of the pings sent, set an interval between them, extend or shorten the TTL, and more. 

On Windows, you can write the following in the Command Prompt and see all the options: 

ping -?

On macOS, you can write the following in the Terminal and see all the options: 

ping -h

On Linux, you can write the following in the Terminal and see all the options: 

ping -h

​Conclusion. 

So, the Ping command is a basic tool for testing devices on your network. It can be found on almost any OS and works almost the same on them. Send ICMP messages and see how long it takes them to return the echo. Simple and perfect.