BIND 10 #2003: support DDNS/TCP response

[BIND 10 Development]

#2003: support DDNS/TCP response
-------------------------------------+-------------------------------------
                   Reporter:         |                 Owner:  jinmei
  jinmei                             |                Status:  reviewing
                       Type:  task   |             Milestone:
                   Priority:  low    |  Sprint-20120612
                  Component:  DDNS   |            Resolution:
                   Keywords:         |             Sensitive:  0
            Defect Severity:  N/A    |           Sub-Project:  DNS
Feature Depending on Ticket:  DDNS   |  Estimated Difficulty:  5
        Add Hours to Ticket:  0      |           Total Hours:  2.12
                  Internal?:  0      |
-------------------------------------+-------------------------------------
Changes (by vorner):

 * owner:  vorner => jinmei
 * totalhours:  0 => 2.12


Comment:

 Hello

 Replying to [comment:8 jinmei]:
 > > Is dropping the connection silently on the quota the best thing to do?
 >
 > I agree that's debatable.  Which options other than this are you
 > thinking about?
 >
 > - returning SERVFAIL or REFUSED?  but it requires to keep the
 >   connection at least until the transmission of the response is
 >   completed.

 It would be possible to at least try sending REFUSED in a non-blocking way
 and drop the connection if it doesn't work. I don't think it would happen
 often that the send would block.

 > - killing oldest client to allow a new client?  Maybe, but maybe not;
 >   if the server is simply busy, it could be possible that the server
 >   is just killing any TCP client before completing any of the
 >   requests.

 We may want to do something like that (or timeout the connections) anyway.
 Otherwise, someone might create few connections and keep them open for
 ever, blocking the server.

 > > And, generally speaking, isn't 10 as the quota really low?
 >
 > This is also debatable, and I'm not sure.  BIND 9's default of
 > tcp-clients (not specific to ddns) is 100, so maybe we should use the
 > same value.  In any case, as long as we use select, we cannot increase
 > it too much due to its scalability.

 Ah, right, select :-|. Well, hopefully, we won't ever reach the limit.

 After looking at the test, I think it can be merged.

-- 
Ticket URL: <http://bind10.isc.org/ticket/2003#comment:10>
BIND 10 Development <http://bind10.isc.org>
BIND 10 Development