asterisk/UPGRADE.txt

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===
=== Information for upgrading between Asterisk versions
===
=== These files document all the changes that MUST be taken
=== into account when upgrading between the Asterisk
=== versions listed below. These changes may require that
=== you modify your configuration files, dialplan or (in
=== some cases) source code if you have your own Asterisk
=== modules or patches. These files also include advance
=== notice of any functionality that has been marked as
=== 'deprecated' and may be removed in a future release,
=== along with the suggested replacement functionality.
===
=== UPGRADE-1.2.txt -- Upgrade info for 1.0 to 1.2
=== UPGRADE-1.4.txt -- Upgrade info for 1.2 to 1.4
=== UPGRADE-1.6.txt -- Upgrade info for 1.4 to 1.6
=== UPGRADE-1.8.txt -- Upgrade info for 1.6 to 1.8
=== UPGRADE-10.txt  -- Upgrade info for 1.8 to 10
=== UPGRADE-11.txt  -- Upgrade info for 10 to 11
=== UPGRADE-12.txt  -- Upgrade info for 11 to 12
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From 12 to 13:
* The per console verbose level feature as previously implemented caused a
  large performance penalty.  The fix required some minor incompatibilities
  if the new rasterisk is used to connect to an earlier version.  If the new
  rasterisk connects to an older Asterisk version then the root console verbose
  level is always affected by the "core set verbose" command of the remote
  console even though it may appear to only affect the current console.  If
  an older version of rasterisk connects to the new version then the
  "core set verbose" command will have no effect.

CLI commands:
 - "core show settings" now lists the current console verbosity in addition
   to the root console verbosity.

 - "core set verbose" has not been able to support the by module verbose
   logging levels since verbose logging levels were made per console.  That
   syntax is now removed and a silence option added in its place.

Configuration Files:
 - The 'verbose' setting in logger.conf still takes an optional argument,
   specifying the verbosity level for each logging destination.  However,
   the default is now to once again follow the current root console level.
   As a result, using the AMI Command action with "core set verbose" could
   again set the root console verbose level and affect the verbose level
   logged.

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