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Re: snmpconf Schedule Requirements





Juergen Schoenwaelder wrote:

> >>>>> Thippanna Hongal writes:
>
> Thippanna> Here is the list of requirement I did compile to associate
> Thippanna> time with the policies.
>
> Thanks for posting this summary. Let me try to rephrase your
> requirements to see whether I did understand you correctly:
>
>   The requirement is to support two additional scheduling types. Both
>   new scheduling types schedule time intervals, which means they create
>   a set operation at the beginning of a time interval and at the end of
>   the time interval.



The scheduler will   operate in the startDateAndTime ,
and  endDateAndTime.
It triggers events at StartTime and at EndTime as specified in the
schedTimeOfDay
and uses masks schedMonth,schedDay, schedDayOfWeek enabling multiple
schedules in the selected range of Dates.
The picture shown will give better picture what I have in mind.

1. as understood
startDateAndTime                               endDateAndTime
|--------------------------------------------------------|
T
T.

2.as required
startDateAndTime                               endDateAndTime
|---|--|---d1---|--|---d2---|--|---d3---|--|---d4---|--|---|
     T T'           T T'           T T'           T  T'          T  T'

T- Trigger indicating the Start of policy
T' - Trigger indicating the End of Policy
dn- Day n, n = 0..31

> It is sufficient if the sets triggered by the
>   scheduler modifies the same integer variable. However, it is necessary
>   to be able to set two different values at the start and the end of the
>   time interval.
>
>   The first new scheduling type (A) specifies the time interval based on
>   calendar time. The second new scheduling type (B) specifies the start
>   point based on calendar time and the duration of the time interval.
>
>   (Well, you actually wrote in your email that the second starts
>   immediately when something (the schedTable entry?) is enabled and runs
>   for the duration specified, but the proposed solution you described is
>   not really consistent with this. Anyway, I will call this variation
>   (B').)

I mean the periodic scheduler time tick start as soon as the schedTable
entry
is enabled. I have no plans to associate this with Calendar Entry  to start
with.

I am exactly looking for: B'
>    (An alternative would be a very slight modification to add
>     a new scheduling type which is basically a periodic schedule
>     which disables itself after the first scheduled event.)

I will again look into the proposed solution, if I need to fix it.

>
>
> Is that summary of the requirements correct so far?
>
> Now lets look what we have right now in RFC 2591. I believe you can
> realize all schedules described above as follows with RFC 2591:
>
> (A)  You create two oneshot schedules in the schedTable, one for
>      the start time and one for the end time.
>
> (B)  Similar to (A), you create two oneshot schedules in the
>      schedTable, one for the start time and one for the end time.  You
>      simply let the manager calculate the end time by adding the time
>      interval to the start time.
>
> (B') You generate a single oneshot schedule for the end time and once
>      the manager has calculated the end time based on the current
>      time. (An alternative would be a very slight modification to add
>      a new scheduling type which is basically a periodic schedule
>      which disables itself after the first scheduled event.)
>
> Now, from looking at the proposed solution, it looks like you are for
> some reason uncomfortable with what I have described above. Is it
> possible to clearly describe why the solutions outlined above do not
> work or are way too ugly in the snmpconf context? Can you provide
> examples to demonstrate your points?
>
> [There are many issues I have with the proposed solutions. But before
>  discussing this in detail, I would first like to better understand
>  what the problem really is. Maybe there are other solutions that fit
>  better into the design of the current scheduler.]
>
> /js
>
> --
> Juergen Schoenwaelder      Technical University Braunschweig
> <schoenw@ibr.cs.tu-bs.de>  Dept. Operating Systems & Computer Networks
> Phone: +49 531 391 3289    Bueltenweg 74/75, 38106 Braunschweig, Germany
> Fax:   +49 531 391 5936    <URL:http://www.ibr.cs.tu-bs.de/~schoenw/>