DNS Zone TXT Records limited to 255 characters - need more

Question

Good day,  
  
New to Amazon Lightsail here. Migrating my instance off another vendor. Instance, firewall, static ip - all went ok. Now setting up my DNS Zone. One of my DNS TXT records is about 400 characters long. It is a google-generated DKIM record which contains key-value pairs including a public key.  
  
When I try to add the record in the DNS Zone Editor, an error pops up: "Each line must be between 0 and 255 characters and contain only printable ASCII characters". But since the 400 characters contain a public key, I don't think I should break it up. Is there any solution to this?  
  
Thanks -Ricardo  
  
Edited by: RigaDorje on Jun 17, 2019 7:42 PM  
  
Edited by: RigaDorje on Jun 17, 2019 7:43 PM

David G · Accepted Answer

Strings in SPF and TXT records should be no longer than 255 characters. However to get around this limitation, per RFC 4408 a TXT or SPF record is allowed to contain multiple strings, which should be concatenated together by the reading application.  
-- https://kb.isc.org/docs/aa-00356

RigaDorje · Answer

Hi David G,  
  
Thanks for the information and the reference link. I broke up the long string by making several lines each less than 255 chars (separated using the Enter key) -- trusting that the reading application will reassemble it back correctly. The editor saved my record.  
  
I then used Mxtoolbox's DKIM Lookup tool  to query the DNS record. It interpreted the DKIM record correctly.  
  
Thank you! -Ricardo

DNS Zone TXT Records limited to 255 characters - need more

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