I have set up an Ubuntu box and everything seems to be working. Website shows, SSL is enabled and I thought everything was as it should but doing a check on mxtoolbox and i get the following warning:
SOA Serial Number Format is Invalid
The serial number is an unsigned 32 bit value assigned to your SOA record must be between 1 and 4294967295.
We will issue a warning if your serial is either invalid by being outside of the allowed range or if it does not conform to this format.
Is this something I have done or is this something related to the Digital Ocean NameServers?
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