Operation and MaintenanceLinux Operation and MaintenanceLinux nslookup command help and DNS lookup examples
nslookup stands for "name server lookup" and is a useful command for obtaining information from DNS servers. It is also very useful for troubleshooting DNS related issues and can query the DNS (Domain Name Server) and get the DNS records for any domain for the IP address.
DNS lookup example
Use the following command to find the address record for a domain. It queries the nameservers and gets the details.
# nslookup google.com
Server: 8.8.8.8 Address: 8.8.8.8#53 Non-authoritative answer: Name: google.com Address: 216.58.219.206
Reverse DNS lookup
You can also use the IP address for reverse DNS lookup, and you can use the IP address to resolve the corresponding domain. Note that this is a different record configured in the reverse zone of the domain.
# nslookup 216.58.219.206
Server: 8.8.8.8 Address: 8.8.8.8#53 Non-authoritative answer: 206.219.58.216.in-addr.arpa name = lga25s40-in-f14.1e100.net. 206.219.58.216.in-addr.arpa name = lga25s40-in-f14.1e100.net. 206.219.58.216.in-addr.arpa name = lga25s40-in-f206.1e100.net. 206.219.58.216.in-addr.arpa name = lga25s40-in-f206.1e100.net.
Query a specific DNS server
You can also query a specific DNS server. Additional parameters need to be passed for the nameserver IP address or domain name. For example, to query the 8.8.4.4 name server, use the following command.
# nslookup google.com 8.8.4.4
Server: 8.8.4.4 Address: 8.8.4.4#53 Non-authoritative answer: Name: google.com Address: 216.58.219.206
Find the SOA record for a domain
Use nslookup to find the SOA (Start of Authorization) record for any domain. For example, to find the SOA records for the domain google.com, you can use the following command. Type-type=soa needs to be specified as a command line parameter.
# nslookup -type=soa google.com
Server: 8.8.8.8
Address: 8.8.8.8#53
Non-authoritative answer:
google.com
origin = ns4.google.com
mail addr = dns-admin.google.com
serial = 159912615
refresh = 900
retry = 900
expire = 1800
minimum = 60
Authoritative answers can be found from:origin: The authority of the source of information.
mail addr: The email address of the domain administrator (the first dot represents the @ symbol in the email address).
serial: Revision data of the domain area, in the format of YYYYMMDDNN.
refresh: The referh interval (in seconds) at which the secondary name server will check the primary name server for updated versions of the zone.
retry: The time to wait for a secondary name server before trying to reconnect to the primary name server after a failed attempt.
expire: The time in seconds for the secondary name server cache to expire.
minimum: The time in seconds that the secondary name server's cache should not be flushed if no time has elapsed since the last flush.
Find a domain’s MX records
You can also query the MX (Mail Exchange) records for any domain, which are responsible for the delivery of email.
# nslookup -query=mx google.com
Server: 8.8.8.8 Address: 8.8.8.8#53 Non-authoritative answer: google.com mail exchanger = 10 aspmx.l.google.com. google.com mail exchanger = 30 alt2.aspmx.l.google.com. google.com mail exchanger = 50 alt4.aspmx.l.google.com. google.com mail exchanger = 40 alt3.aspmx.l.google.com. google.com mail exchanger = 20 alt1.aspmx.l.google.com. Authoritative answers can be found from:
Finding TXT records for a domain
TXT records are useful for many types of records (such as DKIM, SPF, etc.). You can use the command below to find all TXT records configured for any domain.
# nslookup -query=txt google.com
Server: 8.8.8.8 Address: 8.8.8.8#53 Non-authoritative answer: google.com text = "v=spf1 include:_spf.google.com ~all" Authoritative answers can be found from:
Find all records for a domain
Use -query=any to list all records for any domain.
# nslookup -query=any google.com
Server: 8.8.8.8
Address: 8.8.8.8#53
Non-authoritative answer:
Name: google.com
Address: 216.58.219.206
google.com has AAAA address 2607:f8b0:4006:80e::200e
google.com mail exchanger = 20 alt1.aspmx.l.google.com.
google.com mail exchanger = 40 alt3.aspmx.l.google.com.
google.com nameserver = ns2.google.com.
google.com nameserver = ns4.google.com.
google.com nameserver = ns3.google.com.
google.com rdata_257 = 0 issue "pki.goog"
google.com mail exchanger = 30 alt2.aspmx.l.google.com.
google.com mail exchanger = 10 aspmx.l.google.com.
google.com mail exchanger = 50 alt4.aspmx.l.google.com.
google.com text = "v=spf1 include:_spf.google.com ~all"
google.com nameserver = ns1.google.com.
google.com rdata_257 = 0 issue "symantec.com"
google.com
origin = ns2.google.com
mail addr = dns-admin.google.com
serial = 159912615
refresh = 900
retry = 900
expire = 1800
minimum = 60
Authoritative answers can be found from:Nslookup in interactive mode
We can also use nslookup in interactive mode. To enter interactive mode, type nslookup on the console and press Enter. You will get an nslookup prompt such as >. Here, you can run the same query and get the domain's information from the DNS server. Comments have been added between commands for better understanding.
root@tecadmin:~#nslookup ### Type domain name to get information from dns server > google.com Server: 8.8.8.8 Address: 8.8.8.8#53 Non-authoritative answer: Name: google.com Address: 172.217.10.46 ### Set the another specific dns server to query. > server 8.8.4.4 Default server: 8.8.4.4 Address: 8.8.4.4#53 ### Again try to get the dns information, This time nslookup connects to specified dns server. > google.com Server: 8.8.4.4 Address: 8.8.4.4#53 Non-authoritative answer: Name: google.com Address: 172.217.10.46 ### Set the query type. for example to get MX information set query=mx > set query=mx ### Again try to get the dns information, This time nslookup will show MX information for domain > google.com Server: 8.8.4.4 Address: 8.8.4.4#53 Non-authoritative answer: google.com mail exchanger = 30 alt2.aspmx.l.google.com. google.com mail exchanger = 50 alt4.aspmx.l.google.com. google.com mail exchanger = 40 alt3.aspmx.l.google.com. google.com mail exchanger = 10 aspmx.l.google.com. google.com mail exchanger = 20 alt1.aspmx.l.google.com. Authoritative answers can be found from:
This article has ended here. For more exciting content, you can pay attention to other related column tutorials on the php Chinese website! ! !
The above is the detailed content of Linux nslookup command help and DNS lookup examples. For more information, please follow other related articles on the PHP Chinese website!
Linux: Entering and Exiting Maintenance ModeMay 02, 2025 am 12:01 AMThe methods to enter Linux maintenance mode include: 1. Edit the GRUB configuration file, add "single" or "1" parameters and update the GRUB configuration; 2. Edit the startup parameters in the GRUB menu, add "single" or "1". Exit maintenance mode only requires restarting the system. With these steps, you can quickly enter maintenance mode when needed and exit safely, ensuring system stability and security.
Understanding Linux: The Core Components DefinedMay 01, 2025 am 12:19 AMThe core components of Linux include kernel, shell, file system, process management and memory management. 1) Kernel management system resources, 2) shell provides user interaction interface, 3) file system supports multiple formats, 4) Process management is implemented through system calls such as fork, and 5) memory management uses virtual memory technology.
The Building Blocks of Linux: Key Components ExplainedApr 30, 2025 am 12:26 AMThe core components of the Linux system include the kernel, file system, and user space. 1. The kernel manages hardware resources and provides basic services. 2. The file system is responsible for data storage and organization. 3. Run user programs and services in the user space.
Using Maintenance Mode: Troubleshooting and Repairing LinuxApr 29, 2025 am 12:28 AMMaintenance mode is a special operating level entered in Linux systems through single-user mode or rescue mode, and is used for system maintenance and repair. 1. Enter maintenance mode and use the command "sudosystemctlisolaterscue.target". 2. In maintenance mode, you can check and repair the file system and use the command "fsck/dev/sda1". 3. Advanced usage includes resetting the root user password, mounting the file system in read and write mode and editing the password file.
Linux Maintenance Mode: Understanding the PurposeApr 28, 2025 am 12:01 AMMaintenance mode is used for system maintenance and repair, allowing administrators to work in a simplified environment. 1. System Repair: Repair corrupt file system and boot loader. 2. Password reset: reset the root user password. 3. Package management: Install, update or delete software packages. By modifying the GRUB configuration or entering maintenance mode with specific keys, you can safely exit after performing maintenance tasks.
Linux Operations: Networking and Network ConfigurationApr 27, 2025 am 12:09 AMLinux network configuration can be completed through the following steps: 1. Configure the network interface, use the ip command to temporarily set or edit the configuration file persistence settings. 2. Set up a static IP, suitable for devices that require a fixed IP. 3. Manage the firewall and use the iptables or firewalld tools to control network traffic.
Maintenance Mode in Linux: A System Administrator's GuideApr 26, 2025 am 12:20 AMMaintenance mode plays a key role in Linux system management, helping to repair, upgrade and configuration changes. 1. Enter maintenance mode. You can select it through the GRUB menu or use the command "sudosystemctlisolaterscue.target". 2. In maintenance mode, you can perform file system repair and system update operations. 3. Advanced usage includes tasks such as resetting the root password. 4. Common errors such as not being able to enter maintenance mode or mount the file system, can be fixed by checking the GRUB configuration and using the fsck command.
Maintenance Mode in Linux: When and Why to Use ItApr 25, 2025 am 12:15 AMThe timing and reasons for using Linux maintenance mode: 1) When the system starts up, 2) When performing major system updates or upgrades, 3) When performing file system maintenance. Maintenance mode provides a safe and controlled environment, ensuring operational safety and efficiency, reducing impact on users, and enhancing system security.
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
MantisBT
Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.
SublimeText3 Linux new version
SublimeText3 Linux latest version
VSCode Windows 64-bit Download
A free and powerful IDE editor launched by Microsoft
SublimeText3 Chinese version
Chinese version, very easy to use
MinGW - Minimalist GNU for Windows
This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.
