System information

as WAV and GSM), depending on what you specified as the format in the [general]
section of your voicemail.conf file. Your greetings will also be stored in this folder.
Asterisk will not create a folder for any mailboxes that do not have any
recordings yet (as would be the case with a new mailbox), so this folder
cannot be used as a reliable method of determining which mailboxes
exist on the system.
Here’s an example of what might be in a mailbox folder. This mailbox has no new
messages in the INBOX, has two saved messages in the Old folder, and has busy and
unavailable greetings recorded:
/var/spool/asterisk/voicemail/default
./INBOX
./Old
./Old/msg0000.WAV
./Old/msg0000.txt
./Old/msg0001.WAV
./Old/msg0001.txt
./Urgent
./busy.WAV
./unavail
./unavail.WAV
For each message, there is a matching msg####.txt file, which contains
the envelope information for the message. The msg####.txt file is also
critically important for message waiting indication (MWI), as this is the
file that Asterisk looks for in the INBOX to determine whether the mes-
sage light for a user should be on or off.
ODBC
In a centralized or distributed system, you may find it desirable to store messages as
binary objects in a database, instead of as files on the filesystem. We’ll discuss this in
detail in “ODBC Voicemail” on page 378.
IMAP
Many people would prefer to manage their voicemail as part of their email. This has
been called unified messaging by the telecom industry, and its implementation has tra-
ditionally been expensive and complex. Asterisk allows for a fairly simple integration
between voicemail and email, either through its built-in voicemail to email handler, or
through a relationship with an IMAP server. We’ll discuss IMAP integration in detail
in “VoiceMail IMAP Integration” on page 411.
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