[Pdns-users] max record length workaround

Steve Atkins steve at blighty.com
Wed Mar 20 18:14:24 UTC 2019

> On Mar 20, 2019, at 5:49 PM, Jonathan Reed <jreed777 at gmail.com> wrote:
> Hi,
> I'm running an old version of pdns where my backend record length for "records.name" is still varchar(255). I've read it's been extended to 64k. However I'm trying to insert a 400 character dkim value in it by adding multiple records for the dkim to simulate a continuation of the key string. Short of altering the table to allow for the longer lengths, have any of you had experience with the syntax for making long strings like this?
> I've used the conventional escape char \ and tried enclosing the entire string in a paren () but no luck. Perhaps someone else out there has had to do this in the past?

records.name holds the name of the record, e.g. "whatever._domainkey.example.com", not the content, so 255 characters should be just about enough. records.content is where the content lives.

TXT records are limited to strings of 255 characters or less, but can have multiple strings, They'll be concatenated in order by the DKIM validator - I'm guessing that's what you're thinking of.

The syntax for that data in records.content is wrapping each string in the record in double quotes and separating those (two) strings with spaces - so something like '"v=DKIM1\; p=...base64 goop..." "...more base64 goop..."'

I'm not sure whether / why the semicolon needs to be backslash escaped. An homage to bind file format, I guess.


More information about the Pdns-users mailing list