What is DNS query response?
DNS is a query/response protocol. The client queries an information (for example the IP address corresponding to ) in a single UDP request. DNS uses UDP port 53 to connect to the server. TCP can also be used for response data size exceeding 512 bytes or for specific tasks such as zone transfers.
What is a good TTL for DNS?
Generally, we recommend a TTL of 24 hours (86,400 seconds). However, if you are planning to make DNS changes, you should lower the TTL to 5 minutes (300 seconds) at least 24 hours in advance of making the changes.
What do DNS responses contain?
There are many TYPE s of resource records, the most common being A (which gives an IPv4 address for a NAME ), AAAA (which gives an IPv6 address), MX (which sets the location of a mail server), CNAME (or canonical name, which maps one NAME to another), and TXT (which can include any arbitrary text).
How exactly DNS query works?
DNS queries resolve in a number of different ways. The DNS server can use its own cache of resource record information to answer a query. A DNS server can also query or contact other DNS servers on behalf of the requesting client to fully resolve the name, then send an answer back to the client.
Why is Route 53 needed?
Amazon Route 53 provides highly available and scalable Domain Name System (DNS), domain name registration, and health-checking web services. You can also purchase and manage domain names such as example.com and automatically configure DNS settings for your domains.
What type of DNS query is it?
DNS query types
| Query Code | Query Type |
|---|---|
| A | Host Address |
| NS | Authoritative name server |
| MD | Mail destination |
| MF | Mail forwarder |
What is a DNS query message from DNS client?
A DNS Query message from the DNS Client contains mainly below information. 1) Fully Qualified Domain Name (FQDN): Fully Qualified Domain Name (FQDN) of the resource the client is trying to resolve. If there is no DNS suffix provided by the application, the DNS Client will add it.
What is the DNS query response time between Dublin and Seattle?
Between 6 PM and 9 PM in Dublin, 20% of the queries from European clients receive the IP address of the Web server in the Seattle datacenter in their DNS query response. Between 6 PM and 9 PM in Seattle, 20% of the queries from the American clients receive the IP address of the Web server in the Dublin datacenter in their DNS query response.
When should you change the TTL of your DNS records?
When it does come time to enact changes with regard to these types of records, it may behoove you to change the TTL down to a shorter interval before enacting any changes to ensure that the changes are propagated quickly. At the top of every DNS zone, in the Start of Authority (SOA), there are five TTL values that serve a higher purpose in the DNS.
What is SOA TTL and refresh TTL in DNS?
SOA TTL – The interval at which the SOA record itself is refreshed. Refresh TTL – The interval at which slave servers (secondary DNS) are set to refresh the master zone file from the master server.
