In addition to the linux tools, you should familiar with some of the web tools for getting the dns reports. By analyzing the traceroute report, we can trace the IP block at the ISP ( Internet Service Provider ) level or track the network delay in the network path. Using the traceroute result, we can diagnose the trust delays and packet loss at each node in the network path. Traceroute command is used to diagnosing the network. Using the trace option, we can look for the trace of the dns lookup. Customize the results based on the arguments passed with the command. We can look at the dns records from specific dns server using “dig” command. We can use this command to get a specific record or all the records in different ways. digĭig is the most commonly used command to look for the dns records. Now a days ipv6 ip’s are available and ping6 is the command used with ipv6. The normal ping command is for using the ipv4 IP address. Based on the packet loss, we can check for any network issue exists or not. You can see the difference in the time for the rtt from the ping result from a server and from a local ISP.įrom the above result, we can track the round trip time ( rtt ) and the packet loss in the ping. Following is the sample ping result.įrom Local system with less internet speed With local ISP’s the round trip time is around 300 ms and if we check from a server, the time is mostly less than 10 ms. It normally measures the round trip time between the originating host and the destination host. Ping is a network administration tool used for testing whether the destination host is reachable or not.
By selecting the “Name Servers” option, we can confirm whether the name servers are properly registered or not.įor example, the name servers for the domain “ ” are following and you can check the registration details for the name server “ ns.“. There are three options provided in the internic page, they allow us to search for the domain, registrar and for the name servers.
Following is the syntax for the usageįollowing is a web tool available for free for finding the who is report. Using command line, you can pass the domain name as argument for the “whois” command. Either via command line or using any sites, which provide the tool for free. You can check the whois report in multiple ways. The reason for the private registration is due to the misuse of information in the whois report. Most of the case it is not enabled and we can contact the registered owner using the email in the report. In the whois report, we get the whole address of the registered owner with email and phone number unless the private registration is enabled. Registrar details and the authoritative name servers of the domain. From the whois report, we get other information like the registered owner of the domain. Whois is the way to find whether the domain is registered or not. You can check the following screenshots for the details.įollowing is the usage of domain in “host” command:įollowing is the usage of IP in “host” command: Mainly it is used for converting host to IP and vice-versa. Host command is used for performing the dns lookups. You can check the interactive mode from the following screenshot. See the checking of MX record check in the screenshot. We can query specific dns record using the nslookup command by specifying the type. You can check the screenshot for the same.
We can check the rDNS for the IP using the nslookup command. Also in the case of automated scripts, the non-interactive commands are used.
Interactive mode is used for us for manual checking and non-interactive mode help to script the checks for a large number of inputs. Nslookup can be used in two modes interactive and non-interactive mode. Converts the domain name or host to IP address. Nslookup is a service/tool to look up the dns query information. Some are command line and some are web-based.
There are different tools available nowadays and here I am discussing some of the common tools. If you are a system admin you should face the situation to troubleshoot dns issues in your daily work. DNS ( Domain Name System ) is the backbone of the internet and without dns, almost all the services will not work.