在默认情况下，Asterisk的配置文件都保存在/etc/asterisk目录中，以ini文件的格式保存。我们也可以使用数据库来保存大多数Asterisk配置信息。

Asterisk使用数据库保存配置信息有两种方法：静态和动态，对于不经常修改的配置数据，可以使用静态的方式保存，这些数据都是在Asterisk对应的模块加载时获取配置信息。动态方式适合那些经常变化的数据，例如SIP帐号信息。使用数据库来保存SIP帐号信息还有一个好处：Asterisk会自动把SIP帐号登录Asterisk的相关资料保存到表中，这样大大的方便了管理员检查当前SIP帐号的使用情况和状态。

下面开始介绍Asterisk的数据库获取配置的方法。我使用的是Asterisk版本是 11.0.0。

在这里，我只对Asterisk的基本配置和SIP相关的配置感兴趣，AIX帐号的配置和SIP的配置应该类似，不想多作分析。

1. 基本介绍

1.1. 获取数据的方法

配置信息可以保存在多种数据库中，下面是Asterisk支持的数据库的列表和对应的模块：

l odbc res_config_odbc

l sqlite res_config_sqlite

l pgsql res_config_pgsql

l curl res_config_curl

l ldap res_config_ldap

为了通用性，我选择了ODBC作为获得和修改Asterisk配置信息的方式，数据库使用mysql。在这里我不介绍如何安装unixODBC和mysql，只对相关的表和配置文件做介绍。

1.2. 使用到的表结构

1.2.1. 静态配置表

CREATE TABLE `ast_config` (

`id` int(11) NOT NULL auto_increment,

`cat_metric` int(11) NOT NULL default '0',

`var_metric` int(11) NOT NULL default '0',

`commented` int(11) NOT NULL default '0',

`filename` varchar(128) NOT NULL default '',

`category` varchar(128) NOT NULL default 'default',

`var_name` varchar(128) NOT NULL default '',

`var_val` varchar(128) NOT NULL default '',

PRIMARY KEY (`id`),

KEY `filename_comment` (`filename`,`commented`)

)

这个表结构是一个通用的保存各种.conf文件信息的表结构。Asterisk可以让模块的配置信息保存在一个表中，或者分别保存在不同的表中。

下面是表的说明

Column name	Column type	Description
id	Serial, auto-incrementing	An auto-incrementing unique value for each row in the table.
cat_metric	Integer	The weight of the category within the file. A lower metric means it appears higher in the file (see the sidebar). context类型的权重
var_metric	Integer	The weight of an item within a category. A lower metric means it appears higher in the list (see the sidebar). This is useful for things like codec order in sip.conf, or iax.conf where you want disallow=all to appear first (metric of 0), followed by allow=ulaw (metric of 1), then allow=gsm (metric of 2). 变量的权重
filename	Varchar 128	The filename the module would normally read from the hard drive of your system (e.g., musiconhold.conf, sip.conf, iax.conf, etc.). 文件名
category	Varchar 128	The section name within the file, such as [general]. Do not include the square brackets around the name when saving to the database. 类型
var_name	Varchar 128	The option on the left side of the equals sign (e.g., disallow is the var_name in disallow=all). 名字
var_val	Varchar 128	The value of an option on the right side of the equals sign (e.g., all is the var_val in disallow=all). 值
commented	Integer	Any value other than 0 will evaluate as if it were prefixed with a semicolon in the flat file (commented out). 注解

1.2.2. SIP用户表

SIP用户的存储方式在不同的Asterisk版本中差异很大，当看网上的文档的时候很容易犯迷糊，正确的表结构是在Asterisk源码包的下面目录中：

[root@kernel asterisk-11.0.0]# ls contrib/realtime/mysql/sippeers.sql

contrib/realtime/mysql/sippeers.sql

具体的表结构是：

# Table structure for table `sippeers`

CREATE TABLE IF NOT EXISTS `sippeers` (

`id` int(11) NOT NULL AUTO_INCREMENT,

`name` varchar(10) NOT NULL,

`ipaddr` varchar(15) DEFAULT NULL,

`port` int(5) DEFAULT NULL,

`regseconds` int(11) DEFAULT NULL,

`defaultuser` varchar(10) DEFAULT NULL,

`fullcontact` varchar(35) DEFAULT NULL,

`regserver` varchar(20) DEFAULT NULL,

`useragent` varchar(20) DEFAULT NULL,

`lastms` int(11) DEFAULT NULL,

`host` varchar(40) DEFAULT NULL,

`type` enum('friend','user','peer') DEFAULT NULL,

`context` varchar(40) DEFAULT NULL,

`permit` varchar(40) DEFAULT NULL,

`deny` varchar(40) DEFAULT NULL,

`secret` varchar(40) DEFAULT NULL,

`md5secret` varchar(40) DEFAULT NULL,

`remotesecret` varchar(40) DEFAULT NULL,

`transport` enum('udp','tcp','udp,tcp','tcp,udp') DEFAULT NULL,

`dtmfmode` enum('rfc2833','info','shortinfo','inband','auto') DEFAULT NULL,

`directmedia` enum('yes','no','nonat','update') DEFAULT NULL,

`nat` enum('yes','no','never','route') DEFAULT NULL,

`callgroup` varchar(40) DEFAULT NULL,

`pickupgroup` varchar(40) DEFAULT NULL,

`language` varchar(40) DEFAULT NULL,

`allow` varchar(40) DEFAULT NULL,

`disallow` varchar(40) DEFAULT NULL,

`insecure` varchar(40) DEFAULT NULL,

`trustrpid` enum('yes','no') DEFAULT NULL,

`progressinband` enum('yes','no','never') DEFAULT NULL,

`promiscredir` enum('yes','no') DEFAULT NULL,

`useclientcode` enum('yes','no') DEFAULT NULL,

`accountcode` varchar(40) DEFAULT NULL,

`setvar` varchar(40) DEFAULT NULL,

`callerid` varchar(40) DEFAULT NULL,

`amaflags` varchar(40) DEFAULT NULL,

`callcounter` enum('yes','no') DEFAULT NULL,

`busylevel` int(11) DEFAULT NULL,

`allowoverlap` enum('yes','no') DEFAULT NULL,

`allowsubscribe` enum('yes','no') DEFAULT NULL,

`videosupport` enum('yes','no') DEFAULT NULL,

`maxcallbitrate` int(11) DEFAULT NULL,

`rfc2833compensate` enum('yes','no') DEFAULT NULL,

`mailbox` varchar(40) DEFAULT NULL,

`session-timers` enum('accept','refuse','originate') DEFAULT NULL,

`session-expires` int(11) DEFAULT NULL,

`session-minse` int(11) DEFAULT NULL,

`session-refresher` enum('uac','uas') DEFAULT NULL,

`t38pt_usertpsource` varchar(40) DEFAULT NULL,

`regexten` varchar(40) DEFAULT NULL,

`fromdomain` varchar(40) DEFAULT NULL,

`fromuser` varchar(40) DEFAULT NULL,

`qualify` varchar(40) DEFAULT NULL,

`defaultip` varchar(40) DEFAULT NULL,

`rtptimeout` int(11) DEFAULT NULL,

`rtpholdtimeout` int(11) DEFAULT NULL,

`sendrpid` enum('yes','no') DEFAULT NULL,

`outboundproxy` varchar(40) DEFAULT NULL,

`callbackextension` varchar(40) DEFAULT NULL,

`timert1` int(11) DEFAULT NULL,

`timerb` int(11) DEFAULT NULL,

`qualifyfreq` int(11) DEFAULT NULL,

`constantssrc` enum('yes','no') DEFAULT NULL,

`contactpermit` varchar(40) DEFAULT NULL,

`contactdeny` varchar(40) DEFAULT NULL,

`usereqphone` enum('yes','no') DEFAULT NULL,

`textsupport` enum('yes','no') DEFAULT NULL,

`faxdetect` enum('yes','no') DEFAULT NULL,

`buggymwi` enum('yes','no') DEFAULT NULL,

`auth` varchar(40) DEFAULT NULL,

`fullname` varchar(40) DEFAULT NULL,

`trunkname` varchar(40) DEFAULT NULL,

`cid_number` varchar(40) DEFAULT NULL,

`callingpres` enum('allowed_not_screened','allowed_passed_screen','allowed_failed_screen','allowed','prohib_not_screened','prohib_passed_screen','prohib_failed_screen','prohib') DEFAULT NULL,

`mohinterpret` varchar(40) DEFAULT NULL,

`mohsuggest` varchar(40) DEFAULT NULL,

`parkinglot` varchar(40) DEFAULT NULL,

`hasvoicemail` enum('yes','no') DEFAULT NULL,

`subscribemwi` enum('yes','no') DEFAULT NULL,

`vmexten` varchar(40) DEFAULT NULL,

`autoframing` enum('yes','no') DEFAULT NULL,

`rtpkeepalive` int(11) DEFAULT NULL,

`call-limit` int(11) DEFAULT NULL,

`g726nonstandard` enum('yes','no') DEFAULT NULL,

`ignoresdpversion` enum('yes','no') DEFAULT NULL,

`allowtransfer` enum('yes','no') DEFAULT NULL,

`dynamic` enum('yes','no') DEFAULT NULL,

PRIMARY KEY (`id`),

UNIQUE KEY `name` (`name`),

KEY `ipaddr` (`ipaddr`,`port`),

KEY `host` (`host`,`port`)

)

看起来这个表字段很多很吓人，其实最近本的配置就下面几项：

l Name 帐号名字

l Host 设置成dynamic

l Context 设置对应的context

l Type 选择friend

l Secret 帐号密码明文

其他很多字段都是SIP帐号登录时的数据字段。

1.3. 使用到的配置文件

1.3.1. extconfig.conf

最基本的配置文件是extconfig.conf，这个配置文件定义了哪些模块使用数据库的配置，确定了SIP帐号对应的表格。这个配置文件的注释已经基本介绍了它的使用方法，不过没有具体的表的结构。本文上面已经介绍了两个相关的表结构。其他表结构可以在Asterisk源码包的contrib/realtime/目录下找找。

1.3.2. res_odbc.conf

由于我选择了ODBC的数据库连接方式，所以必然的需要ODBC的资源配置。

这个配置文件中，我使用了原来的配置参数：

[asterisk]

enabled => yes

dsn => asterisk

如果是使用yum安装的unixODBC，Asterisk这个数据源在/etc/odbc.ini中定义。

感觉就是：

[asterisk]

Driver = MySQL

Database = asterisk

Servername = localhost

UserName = root

Password = xxxxx

相关的设备在/etc/odbcinst.ini中定义：

[MySQL]

Description = ODBC for MySQL

Driver = /usr/local/lib/libmyodbc5.so

Setup = /usr/local/lib/libmyodbc5w.so

FileUsage = 1

1.3.3. Sip.conf

在sip.conf中有一些和动态实时数据库配置相关的项，这些想对整个配置的实现影响不大，但是涉及是否建立内存缓存，影响性能。

1.3.4. modules.conf

这个文件是Asterisk加载模块的配置文件。要实现配置数据保存到数据库中，必须修改一下加载方法。

下面是modules.conf中相应的注意事项：

; Any modules that need to be loaded before the Asterisk core has been

; initialized (just after the logger has been initialized) can be loaded

; using 'preload'. This will frequently be needed if you wish to map all

; module configuration files into Realtime storage, since the Realtime

; driver will need to be loaded before the modules using those configuration

; files are initialized.

;

; An example of loading ODBC support would be:

preload => res_odbc.so

preload => res_config_odbc.so

任何模块想在Asterisk核心模块初始化之前加载，可以使用preload方式加载。实时驱动相关的模块需要在其他模块加载前加载，这样才能让其他模块使用数据库的配置信息。

2. 静态配置

在这里稍微介绍一个简单的静态配置例子，选择的模块是：musiconhold.conf。

在配置静态配置文件之前，建议先看看extconfig.conf文件的下面内容：

;

; The following files CANNOT be loaded from Realtime storage:

; asterisk.conf

; extconfig.conf (this file)

; logger.conf

;

; Additionally, the following files cannot be loaded from

; Realtime storage unless the storage driver is loaded

; early using 'preload' statements in modules.conf:

; manager.conf

; cdr.conf

; rtp.conf

;

; Named ACLs specified in realtime also can not be used

; from manager.conf unless the storage driver is preloaded.

; Attempting to use a realtime stored named ACL before the

; driver is loaded will result in an invalid ACL which

; rejects all addresses.

2.1. 删除配置文件

$ cd /etc/asterisk

$ mv musiconhold.conf musiconhold.conf.old

2.2. 检查模块加载情况

*CLI> core restart now

*CLI> moh show classes

*CLI>

2.3. 插入数据记录

INSERT INTO ast_config (filename,category,var_name,var_val) VALUES ('musiconhold.conf','default','mode','files');

INSERT INTO ast_config (filename,category,var_name,var_val) VALUES ('musiconhold.conf','default','directory','/var/lib/asterisk/moh');

asterisk=# SELECT filename,category,var_name,var_val FROM ast_config;

filename | category | var_name | var_val

------------------+----------------+--------------+------------------------

musiconhold.conf | default | mode | files

musiconhold.conf | default | directory | /var/lib/asterisk/moh

(2 rows)

2.4. 设置extconfig.conf

在extconfig.conf中加入：

musiconhold.conf => odbc,asterisk,ast_config

2.5. 重载模块

kernel*CLI> module reload extconfig

== Parsing '/etc/asterisk/extconfig.conf': Found

== Binding musiconhold.conf to odbc/asterisk/ast_config

kernel*CLI> module reload res_musiconhold.so

-- Reloading module 'res_musiconhold.so' (Music On Hold Resource)

2.6. 查看数据库中的配置

kernel*CLI> moh show classes

Class: default

Mode: files

Directory: /var/lib/asterisk/moh

3. 动态配置SIP用户信息

在开始做SIP的动态加载之前，先看看extconfig.conf配置文件中的这部分：

; Realtime configuration engine

;

; maps a particular family of realtime

; configuration to a given database driver,

; database and table (or uses the name of

; the family if the table is not specified

;

;example => odbc,asterisk,alttable,1

;example => mysql,asterisk,alttable,2

;example2 => ldap,"dc=oxymium,dc=net",example2

;

; Additionally, priorities are now supported for use as failover methods

; for retrieving realtime data. If one connection fails to retrieve any

; information, the next sequential priority will be tried next. This

; especially works well with ODBC connections, since res_odbc now caches

; when connection failures occur and prevents immediately retrying those

; connections until after a specified timeout. Note: priorities must

; start at 1 and be sequential (i.e. if you have only priorities 1, 2,

; and 4, then 4 will be ignored, because there is no 3).

;

; "odbc" is shown in the examples below, but is not the only valid realtime

; engine. There is:

; odbc ... res_config_odbc

; sqlite ... res_config_sqlite

; pgsql ... res_config_pgsql

; curl ... res_config_curl

; ldap ... res_config_ldap

;

; Note: The res_config_pgsql and res_config_sqlite backends configure the

; database used in their respective configuration files and ignore the

; database name configured in this file.

;

;iaxusers => odbc,asterisk

;iaxpeers => odbc,asterisk

;sippeers => odbc,asterisk

;sipregs => odbc,asterisk ; (avoid sipregs if possible, e.g. by using a view)

;voicemail => odbc,asterisk

;extensions => odbc,asterisk

;meetme => mysql,general

;queues => odbc,asterisk

;queue_members => odbc,asterisk

;acls => odbc,asterisk

;musiconhold => mysql,general

;queue_log => mysql,general

;

sippeers => odbc,asterisk

;

; While most dynamic realtime engines are automatically used when defined in

3.1. 修改extconfig.conf

就修改下面一行，把下面行的注释符去掉。

sippeers => odbc,asterisk

3.2. 修改sip.conf

把下面行的注释符去掉。没考证过不做这步有什么影响。^^

rtupdate=yes ; Send registry updates to database using realtime? (yes|no)

3.3. 添加记录

INSERT INTO sippeers (NAME, HOST,TYPE,context,secret) VALUES ('2012', 'dynamic','friend', 'jluotest','2012')

3.4. 重载模块

kernel*CLI> module reload extconfig

== Parsing '/etc/asterisk/extconfig.conf': Found

== Binding musiconhold.conf to odbc/asterisk/ast_config

== Binding sippeers to odbc/asterisk/sippeers

kernel*CLI> sip reload

Reloading SIP

== Parsing '/etc/asterisk/sip.conf': Found

== Parsing '/etc/asterisk/users.conf': Found

== Using SIP CoS mark 4

== Parsing '/etc/asterisk/sip_notify.conf': Found

3.5. 查看

kernel*CLI> sip show users

Username Secret Accountcode Def.Context ACL ForcerPort

2134 not_very_secret jluotest No No

2136 peekaboo jluotest No No

2133 peekaboo jluotest No No

看到的只有在sip.conf中配置的用户。

3.6. 用2011登录

似乎默认情况下不会显示对应的数据库中配置的用户，只有该用户登录后才显示。下面是2011登录后，再查看SIP用户列表的情况：

-- Unregistered SIP '2011'

-- Registered SIP '2011' at 192.168.0.11:4604

> Saved useragent "Linphone/3.5.2 (eXosip2/3.6.0)" for peer 2011

kernel*CLI> sip show users