How can DNS host limitations break authentication?

DNS provider limitations affecting email:

TXT record length: Some providers truncate long records. Breaks DKIM keys or complex SPF.

TXT string splitting: Improper handling of multi-string records corrupts data.

Record count limits: Restrictions on total records or records per name.

Character restrictions: Some providers reject special characters or require escaping.

Propagation delays: Slow updates cause extended authentication failures during changes.

No API access: Cannot automate DKIM key rotation or SPF updates.

Before committing to a DNS provider, test that they properly handle 2048-bit DKIM keys and complex SPF records.

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