What should I do about domain name DNS common problems? Summary of practical solutions

in the process of domain name management and website operation and maintenance, domain name DNS is the core bridge connecting the domain name and the server. Once a problem occurs, it can lead to slow website access, and it can directly cause failures such as website inaccessibility and email service interruption, which brings unnecessary losses to enterprises or individuals. Many managers are often at a loss when encountering domain name DNS problems, and do not know where to start to investigate and solve them. This article will sort out various common problems of domain name DNS, and give targeted and practical solutions based on actual operation and maintenance experience to help everyone deal with related faults efficiently and ensure the stable operation of domain name services.

How to solve the DNS resolution delay of domain name?

domain name DNS resolution delay is one of the common access problems, users need to wait for a long time after entering the domain name to jump to the website page, seriously affecting the access experience.

1, the replacement of high-quality domain name DNS service providers

the node distribution and resolution speed of different domain name DNS service providers vary greatly, and some small service providers have limited node coverage, which can easily lead to cross-regional resolution delays. You can choose domestic mainstream public domain name DNS service providers, such as Alibaba Cloud DNS, Tencent Cloud DNS, etc. Such service providers have node clusters all over the country, which can automatically assign the nearest resolution node according to the user's area, greatly reducing the resolution response time.

2, open the domain name DNS cache optimization

reasonably set the cache time parameter of the domain name DNS, in the case that the domain name record does not need to be modified frequently, appropriately extend the TTL value, that is, the survival time, so that the local DNS server and user browser can cache the resolution result for a longer time and reduce the number of repeated resolutions. However, it should be noted that if there is a domain name resolution adjustment plan in the near future, the TTL value should be temporarily reduced in advance to avoid access abnormalities caused by conflicts between old and new resolution records.

Second, how to correct the misconfiguration of domain name DNS records?

domain name DNS record configuration error is one of the core reasons that cause the website to be inaccessible. Common problems such as A record pointing error and MX record configuration confusion.

1, check the domain name DNS record type and value

first to clarify the role of different record types, A record is used to point the domain name to the IPv4 address, AAAA record corresponds to the IPv6 address, MX record is responsible for the routing of mail services. After finding an access failure, log in to the domain name management background first, and check whether the pointing values of various records are correct one by one, such as whether the Internet Protocol Address of A record is consistent with the server's public network IP, and whether the priority of MX records and the mail server address meet the requirements of service providers.

2, use domain name DNS detection tool to verify

manual verification is prone to omissions, you can use professional domain name DNS detection tools, such as the DNS query function of the webmaster tool, Dig command, etc., after entering the domain name, you can quickly obtain the resolution results of each node in the whole network, compare the records of different nodes, and find the configuration error or not synchronized in time. After modifying the record, you can also monitor the effective status of the analysis in real time through the tool to ensure that the configuration is accurate.

What are the methods for rapid troubleshooting of domain name DNS faults?

when the site can not access the situation, quickly locate the domain name DNS fault is the key to solve the problem, to avoid blind troubleshooting waste of time.

1, local domain DNS cache refresh and detection

first troubleshoot the domain name DNS cache of the local device. The Windows system can perform the ipconfig /flushdns command to refresh the cache through the command line, and the Mac system uses the sudo killall -HUP mDNSResponder command. After the refresh, try to access the website again. If it returns to normal, it means that the old resolution record of the local cache is caused by the problem.

2, layer by layer troubleshooting domain name DNS resolution link

start from the local DNS server and troubleshoot the resolution link layer by layer. First use the nslookup command to query the local DNS resolution results of the target domain name, and then query the resolution records of the top-level domain server and the authoritative domain name server. Compare whether the results of different levels are consistent, and locate which level of domain name DNS service is abnormal. For example, the failure of the authoritative server will lead to the failure of the whole network resolution, and the local DNS failure will only affect a single user or local network.

4, how to strengthen the domain name DNS security protection?

domain name DNS is not only about access speed and stability, but also the risk of being attacked, such as DNS hijacking, cache poisoning, etc., which will lead to users being directed to malicious websites and cause information leakage.

1, open the domain name DNSSEC security extension

DNSSEC is a security extension protocol that verifies the authenticity and integrity of domain name resolution records through digital signature technology and prevents the resolution records from being tampered with. At present, mainstream domain name registrars and DNS service providers support the DNSSEC function. After opening, the user device will automatically verify the signature when obtaining the resolution result, effectively resisting DNS hijacking and cache poisoning attacks.

2, set the domain name DNS operation authority control

strengthen the authority control of the domain name DNS management background, set complex login passwords, and open the secondary verification function to avoid malicious analysis and modification caused by account theft. At the same time, regularly clean up unnecessary authorized accounts, retain only the operation authority of core operation and maintenance personnel, and reduce the risk of internal misoperation or external malicious attacks.

To sum up, domain name DNS is the core link of domain name service, from parsing delay, configuration error to troubleshooting and security protection, each link has corresponding solutions. Daily operation and maintenance should regularly check the running status of domain name DNS, reasonably configure relevant parameters, and gradually locate according to the troubleshooting logic when encountering problems. It can efficiently solve various common faults, ensure the stable and safe operation of domain name service, and provide users with a smooth access experience.