DNSBench is a program for testing DNS servers. Testing DNS servers

The standard procedure for testing DNS servers is launched when registering a new domain in the RU, SU or RF domain and when automatic change data in the domain (in cases where the list of servers in the received application is not empty). For the .RU and .РФ domains, a successfully completed mobile authorization is required.

Testing is carried out for four days every three hours until the first successful test. Testing is considered successful if all DNS servers listed in the received application meet the requirements of clause 4.5 of the Domain Registration Regulations in the RU and RF domains and the Domain Registration Regulations in the SU domain, as well as recommendations for filling out the dns-servers field. After each unsuccessful attempt testing is sent accordingly automatic message about an error to the contact address specified in the Agreement (section Registration information to User).

If the area has not been tested within four days, testing stops.

Wherein:

• When registering a new domain, it is not delegated.
• If you try to change domain information, the list of DNS servers is not replaced with a new one. The domain remains delegated with the old list of DNS servers.

The list of DNS servers that are in the process of testing and the list of DNS servers contained in the database can be viewed in the User control panel, section Services, DNS servers.

DNS server testing sequence

If the check fails for any of the items, an error message is sent.

Example:

• Checks if the list of DNS servers is empty

For each DNS server specified in the list, the IP address is determined:

Nslookup server_name

For DNS servers whose name contains the name of the delegated domain, IP addresses are taken from the application.

• It is checked whether specified name DNS server synonym (CNAME).
• Checks whether the list of DNS servers contains at least two DNS servers located in different networks class C.

Each DNS server specified in the application is requested from any of its IP addresses for an SOA record and a list of DNS servers for this domain:

Nslookup -q=any >server Server_IP address >domain name

The SOA record and list of DNS servers for the domain must be obtained from all DNS servers.

• SOA records received from all DNS servers are compared. SOA records on all DNS servers must be identical (all parameters except serial are compared).
• The lists of DNS servers for the domain received from all DNS servers are compared. The lists of DNS servers for the domain must be identical.

Special procedure for testing DNS servers

A special procedure for testing DNS servers is used by the Administrator if it is necessary to check the functionality of the DNS servers specified in the database for the domain. The procedure is launched manually for any domain. If the list of DNS servers no longer meets the requirements of clause 4.5 of the Regulations for registering domain names in the .RU and .РФ domains and clause 4.5 of the Regulations for registering domain names in the .SU domain, the delegation of the domain can be removed.

The testing sequence is similar standard procedure testing.

In case of unsuccessful testing, a letter is sent to the mnt-nfy address specified in the Domain Administrator Agreement notifying about the unsuccessful testing of DNS servers and diagnosing errors during testing. The letter contains the date of possible suspension of delegation.

If an area has not been tested within four days, testing stops and email addresses and mnt-nfy specified in the Domain Administrator Agreement, a letter is sent notifying that the list of DNS servers does not meet the requirements of clause 4.5 of the Regulations, and therefore the delegation of the domain is temporarily lifted. In this case, the domain will not be released or deleted from the database.

Domain delegation will be restored after receiving an order to change the list of DNS servers and their successful testing (standard procedure).

Requirements for DNS servers when delegating a domain. Some recommendations for filling out the dns-servers fields when entering into the database.

1. For DNS servers whose name contains the name of the delegated domain, you must specify the IP address. For example:

   Domain: newtime.ru dns-server: ns.newtime.ru 193.123.45.67 dns-server: ns3.newtime.ru

   IN in this case the machine will report an error because the server name ns3.newtime.ru contains the name of the delegated domain, and you must specify its IP address.

2. The sequence in which DNS servers are listed does not matter, because They are entered into the database in alphabetical order.

At least two of the listed DNS servers must be located on different IP networks (in various networks class C in traditional terminology) and have reliable connection to the Internet. By “reliable connection” we mean one in which the total time of no connection with the server does not exceed two hours a day. For example:

Dns-server-1: ns.newtime.ru 193.123.45.67 dns-server-2: ns2.newtime.ru 193.123.45.68

In this case, the primary and secondary DNS servers are located in the same class C network, the machine will report an error.

3. DNS records for this domain on all DNS servers from the presented list must be identical (all parameters except serial are compared).

The symbolic name of the DNS server cannot be shortened, i.e. completely match the name of the registered domain, for example:

Domain: test.ru dns-server: test.ru 121.121.121.121

IN similar situation the machine will inform you that it is impossible to use this DNS server name.

4. You cannot use CNAME records to determine server names. When checking the zone's health, these names are replaced with canonical ones, which leads to error messages.

7 answers

• Whois is the only 100% sure way to check domain.co.za availability. See http://co.za/whois.shtml
• My tests show that the presence check NS records or ANY DNS records seems to be the most accurate way to guess whether the domain.co.za is available for registration. SOA records they also work, but not in the same way.
• dig co.za. NS shows.co.za TLD nameservers. Ping TLD and use the closest ones to avoid unnecessary recursive requests.

Thank you for your responses.

The only one reliable way Domain availability checks are a 100% query to the registrar's database. I wouldn't trust whois.

You can use DNS to get the score. Instead of looking for the SOA record, I would just look to see if there is anything listed at all with the TLD nameserver. dig- good tool for this (works on Windows too), although I think you can use nslookup too. For example:

Dig co.za. N.S.

will provide a list of nameservers for.co.za. One of these servers is ns0.is.co.za.

Then query that server to see if they have anything listed for the domain you're interested in:

Dig ibm.co.za @ns0.is.co.za

This query returns NS records, but the SOA record is not written with SOA records by the domain name server (which may or may not be on the network). NS records indicate that Domain name used.

The reason for going directly is that it is usually much faster than relying on recursive queries from your local server names

The only way to determine whether a domain is available or not is to query the registry database for that domain. You can usually do this by running a WHOIS query in the registry's WHOIS interface.

There are several reasons to explain why DNS check unsafe.

The simplest explanation is that you can register a domain without having to list it anywhere. It's like home. You can buy a house, but you don't have to build a road to get there.

Most of the available domain providers force you to specify DNS, otherwise they set it to default. But you are not forced, this is not a mandatory domain requirement.

The second reason is that there are actually cases where a domain is registered but not available. One such instance is the period often referred to as the redemption period. This period lasts several days after the domain expires and the current owner does not renew it. Several registries disable a domain, meaning that it is no longer available via DNS, but the domain still exists and can only be purchased (usually) by the original owner.

DNS checking is cheap and sometimes faster. If you need to check if a domain exists, you can try a DNS query first, and if that fails, drop the WHOIS query. In other words, , If DNS query is executed, the WHOIS query is almost meaningless. But you can't do the opposite because if a DNS query fails, it does not mean the domain is not registered.

On practice DNS lookup works 99% of the time. If you write something like Ajaxwhois, I'd suggest going that route. If you have a million names to check, I'll do a first pass with a DNS lookup and then maybe do a second pass on the ones you might consider purchasing.

Hi all! Today we'll talk about how to check DNS servers for blocking provider or home router. After all, if you remember, we have already raised this topic.

In general, the essence of this problem is that it is with the help of such servers that the letter name of a site on the Internet is compared with its real IP address.

That is, look, let’s take for example this blog. It is located at . This is a letter name that corresponds to the following IP address:

But you must admit that memorizing such a sheet of numbers is not very convenient. That is why DNS servers were introduced, which allow you to access resources using a domain name that consists of Latin letters.

So, guys, we need to understand the fact that every provider uses these servers. Thus, he can block resources he does not like by setting required parameters DNS

Knowing this, we can easily bypass such restrictions by specifying in the settings network card computer alternative servers, where the mapping of domain names to IP addresses occurs according to a different scenario:

The provider, of course, also knows about the possibility of such manipulation. Therefore, it often deliberately blocks the use of third-party DNS servers. And to check this, you need to do the following simple steps.

And enter this line in it:

As already mentioned at the beginning of the publication, in the previous article we used this method to bypass the installation restriction on Samsung TVs. So, in that case, to check it was necessary to enter a command like this:

And if the answer is as shown in the screenshot above, then there is no blocking. If you see something similar to this:

This means that third-party servers are blocked. Alternatively, it’s worth looking at what DNS addresses are registered in yours, or call your provider and see what’s what.

And we’ll wrap up, since the topic of how to check DNS servers for blocking has been exhausted. If you have any questions, please leave them in the comments. And finally, I suggest you look educational video about human sleep.

DNSBench (Domein Name Server Benchmark) is simple utility, which helps you quickly test your work DNS servers and give preference for configuration as primary and alternative DNS, depending on speed and stability. You can download the DNS test program from our website with preferred settings for Belarus, Russia, Ukraine

I must say that the utility has not been updated for a long time (since the end of 2010), but it works well on all operating systems Windows systems, i.e. setting or not required.

Exist alternative programs to carry out the test and select the main and alternative DNS server. DNSBench was chosen for its ability to initially test only those servers that work stably and quickly in the named regions: Belarus, Russia, Ukraine (others from the former union).

Thus, DNSBench will help you test DNS speed servers without additional settings and very quickly. The program may be useful in case of errors when DNS work provider servers. Including when errors occur frequently.

Configuration, installation, system requirements DNSBench

The DNSBench program consists of a single .exe file and does not need to be installed on a computer or laptop. The archive with the program contains a configuration file.ini for quick setup the most common servers for the CIS. Configuration file for correct operation must be in the same folder - this is the only configuration requirement.

Websites, utilities and programs for testing a DNS domain:

Below is how and what you can do test DNS.

Free sites where you can check DNS:

Paid sites for DNS testing

This service used to be free, now the owners charge subscription fee for using the service. When it was free, I used it quite often, since the service shows errors in DNS settings domain.
If you can pay, I highly recommend it for system administrators
http://www.dnsstuff.com/products/dnsreport

Utilities used for DNS testing

nslookup- (from English: name server lookup search on a name server) - a utility that provides the user with an interface command line to access the DNS system. Allows you to set Various types queries and query arbitrarily specified servers. Its analogues are the host and dig utilities. Developed as part of the BIND package (for UNIX systems).
The utility is ported to Windows directly by Microsoft and comes with operating system.
Detailed description nslookup on Wikipedia: http://ru.wikipedia.org/wiki/Nslookup

dig- (from the English word “dig”, and formally - an abbreviation for “domain information groper”) - a utility (DNS client) that provides the user with a command line interface for accessing the DNS system. Allows you to specify different types of requests and request arbitrarily specified servers. It is an analogue of the nslookup utility.
The dig utility comes standard with a BIND DNS server.
Detailed description dig on Wikipedia: http://ru.wikipedia.org/wiki/Dig