[asterisk-bugs] [DAHDI-linux 0013205]: [patch] bad master selection

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=13205 
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Reported By:                biohumanoid
Assigned To:                kpfleming
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Project:                    DAHDI-linux
Issue ID:                   13205
Category:                   dahdi (the module)
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     assigned
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Date Submitted:             2008-07-31 00:11 CDT
Last Modified:              2009-03-06 13:25 CST
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Summary:                    [patch] bad master selection
Description: 
Current dahdi master handling work in the following way:
The first SPAN become a master
If a new registered !!! SPAN is preferred , it is the new master
If a span is unregistered - the new master is the first available span
If master SPAN is in alarm state - the new master is the first non in
alarm state SPAN

So
1. dahdi-dummy once loaded will be the master forever.
2. even not-running SPAN can be a master
3. master implementation is ugly...
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 (0101313) sruffell (administrator) - 2009-03-06 13:25
 http://bugs.digium.com/view.php?id=13205#c101313 
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madrouter, biohumanoid: Thanks for that.  I haven't yet done anything with,
or thought about, dynamic spans so I do see how the sync_tick can be used
there.  I still need to read through the xpp drivers to see how it makes
use of the sync_tick.

The drivers that I work on can not use any host software based mechanism
to control the rate at which samples are shifted out on the interface.  So,
for me, the master span was only used to determine when conferencing took
place, etc..

I'm looking at this issue because I'm thinking about moving the
functionality of dahdi_dummy directly into dahdi-base.c, and then allow
dahdi to to determine if it should use internal timing or timing from an
attached span like is being discussed here.  That would be one less thing
for new users to understand and hopefully reduce supported related to
questions about timing. 

Issue History 
Date Modified    Username       Field                    Change               
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2009-03-06 13:25 sruffell       Note Added: 0101313                          
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