SOA "minimum" vs "negative ttl"
j.tavares at F5.com
Thu Jan 24 01:05:33 UTC 2013
I believe that RFC 2308 redefines the SOA "minimum" field to be
If I create a dynamically updated zone file that looks like so:
new.com IN SOA d62.test.com. hostmaster.d62.test.com. 2013012301 10800 3600 604800 86400
new.com IN NS d62.test.com.
When a DNS update comes into to add or modify a record and bind eventually re-writes
the master file it will rearrange the SOA and add comments (which is fine) but it labels
the last field as "minimum"
$TTL 500 ; 8 minutes 20 seconds
new.com IN SOA d62.test.com. hostmaster.d62.test.com. (
2013012302 ; serial
10800 ; refresh (3 hours)
3600 ; retry (1 hour)
604800 ; expire (1 week)
86400 ; minimum (1 day)
a A 18.104.22.168
Is there a reason for this or is it just a hold over?
It is perpetrating a misconception that this is the minimum TTL.
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