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BIND9 Documentation for SOA resource record timing fields?

GRO 108
GRO 108 Posts: 46
in LFS211 Class Forum - Discontinued

I've been trying to make use of the documentation bundled with packages as much as possible to reduce my reliance on external resources but in this case I haven't been able to find anything in the BIND documentation for the fields relating to TTL etc on SOA records.

i.e.

     SERIAL   ; serial number in YYYYMMDDRR
     REFRESH   ; time to refresh
     RETRY   ; time to retry
     EXPIRE   ; time to expire
     NEGATIVE TTL   ; negative ttl

It's well known that these fields are required but where is that defined by BIND?

P.S The wikipedia entry for SOA is helpful for a concise definition https://en.wikipedia.org/wiki/SOA_record

Comments

  • lee42x
    lee42x Posts: 380

    The "Administrators Reference Manual" or "ARM is part of the source package. Documentation can also be found at https://kb.isc.org/docs/aa-01493 . All of the field definitions are in the ARM.

    One handy item when building DNS, is the loopback zone configuration. I start by copying the loopback configuration files to my new domain-name and edit from there. Sort of a built in example or template when starting from scratch.

  • GRO 108
    GRO 108 Posts: 46

    Thanks for the tip @lee42x

    Can you give me a reference in the ARM to the field definitions? I can't find them.

  • lee42x
    lee42x Posts: 380

    Is this what your looking for?

    The BIND ARM:
    https://downloads.isc.org/isc/bind9/9.17.4/doc/arm/html/reference.html#resource-records

    Then it points to :
    https://en.wikipedia.org/wiki/List_of_DNS_record_types

    Which points to:
    RFC1035 and RFC2308

    Below is a selection from RFC1035:

    Mockapetris [Page 18]

    RFC 1035 Domain Implementation and Specification November 1987

    3.3.13. SOA RDATA format

    +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/                     MNAME                     /
/                                               /
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
/                     RNAME                     /
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|                    SERIAL                     |
|                                               |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|                    REFRESH                    |
|                                               |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|                     RETRY                     |
|                                               |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|                    EXPIRE                     |
|                                               |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|                    MINIMUM                    |
|                                               |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+

    where:

    MNAME The of the name server that was the
    original or primary source of data for this zone.

    RNAME A which specifies the mailbox of the
    person responsible for this zone.

    SERIAL The unsigned 32 bit version number of the original copy
    of the zone. Zone transfers preserve this value. This
    value wraps and should be compared using sequence space
    arithmetic.

    REFRESH A 32 bit time interval before the zone should be
    refreshed.

    RETRY A 32 bit time interval that should elapse before a
    failed refresh should be retried.

    EXPIRE A 32 bit time value that specifies the upper limit on
    the time interval that can elapse before the zone is no
    longer authoritative.

    Lee

  • GRO 108
    GRO 108 Posts: 46

    It absolutely is :smiley: Thanks @lee42x

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