What is the purpose of TTL in a DNS record?

TTL (Time To Live) in a DNS record specifies the duration in seconds that cached DNS servers and clients can store this record before querying the authoritative server again.

This is important for balancing data freshness and DNS server load:

• A small TTL allows for quick updates, which is useful when IP addresses change frequently.
• A large TTL reduces the number of requests to the server, improving performance and reducing delays.

For example, if the TTL is set to 3600 seconds, the DNS client will use the cached record for an hour before requesting an update.