TTL – meaning
Time To Live (TTL) is the value that indicates how long the data should be stored in a particular device. A lot of data pieces hold their own TTL value.
If we speak about DNS TTL, it refers to the time the DNS resolvers have to store the DNS records in their cache memory. Every DNS record also has its own TTL value. Some of them have longer TTL because the chance is less for the value to change. Yet, others have shorter TTL values, where changes more often happen.
Here is a basic illustration of values as an orientation for your DNS records:
- A and AAAA records – 2 hours (7200 seconds)
- CNAME records – up to 12 hours (43200 seconds)
- TXT records – up to 12 hours (43200 seconds)
- MX records – 1 hour (3600 seconds)