Best practices for using TTL (2024)

FAQs

Best practices for using TTL? ›

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. After the changes are made, increase the TTL back to 24 hours.

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. After the changes are made, increase the TTL back to 24 hours.

Setting appropriate TTL values for your SOA record type is necessary for balancing performance and the speed of DNS propagation. Shorter TTLs can help in rapidly updating changes but may increase the load on your DNS servers. Longer TTLs reduce server load but slow down the propagation of updates.

For records that point to your web server, we typically recommend setting TTL at 86400 (24 hours), depending on the frequency of which your records need to be updated. The reason TTL values are so important is that they are what dictates how long a resolver will cache your DNS record information.

It is recommended that you set your TTL for something longer than the average session time (which is between 2-3 minutes). TXT Record: Widely used for DKIM records, email security and verifying domain ownership. TXT records are rarely changed so anywhere within the 1 – 12-hour timeframe should suffice.

TTL uses two logic levels: high and low. The high-level voltage, typically around 5 volts, represents logic "1," while the low-level voltage, typically around 0.4 volts, represents logic "0." These voltage levels are standardized to ensure compatibility between TTL devices.

A common recommendation for DNS records that are generally static in nature is a TTL of an hour or even longer, up to a few days. This is especially true for NS records. NS records are critical in the DNS, so they should usually be relatively static and have somewhat longer TTLs than other records in the DNS.

Longer TTL values are best used for records that do not change frequently and/or are part of a stable and static infrastructure. Shorter TTL values are better for records that are expected to change frequently.

A TTL of 1800 to 3600 is recommended for CNAME/ANAME/MX/HTTP redirection records, with a preference toward a higher TTL. Since these records will be pointing to other records that will be making the changes, changes for these records will be rare.

Does TTL time matter? ›

TTL values impact the query volume connected to the authoritative name server. If a DNS cache holds a record too long, changes to the record take longer to propagate, potentially slowing down a user's search or resulting in an error message.

The maximum TTL value is 255, the maximum value of a single octet. A recommended initial value is 64. The time-to-live value can be thought of as an upper bound on the time that an IP datagram can exist in an Internet system.

A TTL input signal is defined as "low" when between 0 V and 0.8 V with respect to the ground terminal, and "high" when between 2 V and V_CC (5 V), and if a voltage signal ranging between 0.8 V and 2.0 V is sent into the input of a TTL gate, there is no certain response from the gate and therefore it is considered " ...

For records that rarely change (such as TXT or MX records), it is best to keep the TTL between one hour (3600 seconds) and 24 hours (86400 seconds). Then, when you need to make a change to the record, you can reduce the record TTL value temporarily before making the change to expedite propagation.

TTL is measured in seconds. The typical default value is usually 12 hours (43200 seconds) or 24 hours (86400 seconds). This means that if, for example, a website moves to a new server or you add a new URL to your server, it takes 12 or 24 hours for the new DNS changes to take effect.

Don't overcomplicate your topside TTL testing. Two shots: one with the strobes pointed away from the camera and one with the strobes pointed towards the lens will tell you whether the TTL is functioning correctly. If the strobe output changes from bright flashes to small blips of light then you're good to go.

We recommend a TTL of 1-24 hours for most sites. Remember that TTL values are measured in seconds, so this is the equivalent of 3,600 to 86,400 seconds.

For any critical records, you should always keep the TTL low. A good range would be anywhere from 30 seconds to 5 minutes.

Windows typically utilizes a default TTL value between 126 to 128. Linux and Unix-like systems commonly opt for a default TTL value between 62 to 64.