SOA Expire Value out of recommended range

Error message:

ns1.cweiske.de reported Expire 1048576 : Expire is recommended to be between 1209600 and 2419200.

RFC 1912 says:

2.2 SOA records

Expire: 2-4 weeks are suggested values.

• 2 weeks: 2*24*60*60 = 172800
• 4 weeks: 4*24*60*60 = 345600

Test:

$ dig @ns1.cweiske.de +short SOA cweiske.de
ns1.cweiske.de. hostmaster.cweiske.de. 1589436247 16384 2048 1048576 2560
                                       |          |     |    |       +minimum
                                       |          |     |    +expire
                                       |          |     +retry
                                       |          +refresh
                                       +-serial

Links:

• https://en.wikipedia.org/wiki/SOA_record
• https://tools.ietf.org/html/rfc1912#section-2.2
• https://cr.yp.to/djbdns/tinydns-data.html

tinydns seems to set the expire time automatically to 1048576 (12.x days)

SOA Serial Number Format is Invalid

Error was:

ns1.cweiske.de reported Serial 1589436247 : Suggested serial format year was 1589 which is before 1970.

Reason: tinydns uses the unix timestamp as serial, not the YYYYMMMDDHHIISS format

Serial numbers do not match

Output was:

1589436247<br/>1589423702

Reason: I updated the zone file on my server, and the secondary name server had not yet copied the new zone data to itself via AXFR.

Links:

• https://cweiske.de/tagebuch/axfr-fails.htm