Re: Re: MIBDoctorreview:publishdraft-ietf-disman-remops-mib-v2-06.txt

Hi -

As a technical contributor...

> From: "Juergen Schoenwaelder" <[email protected]>
> To: "Randy Presuhn" <[email protected]>
> Cc: "Disman" <[email protected]>
> Sent: Monday, July 04, 2005 1:01 PM
> Subject: Re: [Disman] Re: MIBDoctorreview:publishdraft-ietf-disman-remops-mib-v2-06.txt
...
> The results table uses the InetAddress convention to return the
> results. For DNS names, the InetAddressType would be dns(16). For
> other names, unknown(0) seems applicable.  The unfortunate news
> is that without some effort, there is no way to decide whether
> the name returned by gethostbyaddr() is a DNS name or not.

The value of the InetAddressType qualifies the *syntax* of the InetAddress.
It doesn't indicate where the information "came from".  If something is
syntactically a DNS name, I believe the InetAddressType would be dns(16),
even if the value had been entered by a human or read from a paper tape.

> Another question concerns dual hosts with multiple names for different
> addresses which may actually life in different address domains. Can an
> application just pick randomly one address, call gethostbyaddr() or
> getnameinfo() and report the result? Or is it required to collect
> and consolidate the information for all IP addresses? The current ID
> uses language such as "official name" or "primary address" which are
> not well defined.
...

I think section 3.3.3 paragraphs 4..6 address this by giving an operational
definition of the required behaviour:

   The gethostbyaddr function is called with a host address as its
   parameter and is used primarily to determine a symbolic name to
   associate with the host address.  Entries in the lookupResultsTable
   MUST be made for each host name returned.  The official host name
   MUST be assigned a lookupResultsIndex of 1.

   The gethostbyname function is called with a symbolic host name and is
   used primarily to retrieve a host address.  Normally, the first
   h_addr_list host address is considered to be the primary address and
   as such is associated with the symbolic name passed on the call.

   Entries MUST be stored in the lookupResultsTable in the order that
   they are retrieved.  Values assigned to lookupResultsIndex MUST start
   at 1 and increase in order.

In otherwords, whatever gethostbyname() / gethostbyaddr() list first
is what will be considered  "primary".  I don't think we can do much
better than that with the tools available to us.

Randy