Synopsis
Addressing MySQL Database failover in the Asterisk Dialplan
Introduction
HA installations require failover in event of a database failure. Included here are some dial plan configurations that can facilitate switchover inside of the dialplan.
Extensions.conf
[globals]
DBDefaultHost=192.168.170.21
DBBackupHost=192.168.170.22
DBCurrentHost=192.168.170.21
DBname=astdb
DBuser=root
DBpass=stellance
[macro-db-connect]
exten => s,1,MYSQL(Connect connid ${DBCurrentHost} ${DBuser} ${DBpass} ${DBname})
exten => s,n,GotoIf($[“${connid}” = “”]?changedb)
exten => s,n,MacroExit
exten => s,n(changedb),NoOp(“Switching DB Servers”)
exten => s,n,GotoIf($[“${DBCurrentHost}” = “${DBDefaultHost}”]?backup)
exten => s,n,Set(DBCurrentHost=${DBDefaultHost}|g)
exten => s,n,Macro(write-cdr_mysql)
exten => s,n,MacroExit
exten => s,n(backup),Set(DBCurrentHost=${DBBackupHost}|g)
exten => s,n,Macro(write-cdr_mysql)
exten => s,n,MacroExit
[macro-write-cdr_mysql]
exten => s,1,System(/bin/echo “‘[global]'” > /etc/asterisk/cdr_mysql.conf)
exten => s,n,System(/bin/echo “‘hostname=${DBCurrentHost}'” >> /etc/asterisk/cdr_mysql.conf)
exten => s,n,System(/bin/echo “‘dbname=astdb'” >> /etc/asterisk/cdr_mysql.conf)
exten => s,n,System(/bin/echo “‘table=cdr'” >> /etc/asterisk/cdr_mysql.conf)
exten => s,n,System(/bin/echo “‘password=stellance'” >> /etc/asterisk/cdr_mysql.conf)
exten => s,n,System(/bin/echo “‘user=root'” >> /etc/asterisk/cdr_mysql.conf)
exten => s,n,System(/bin/echo “‘port=3306′” >> /etc/asterisk/cdr_mysql.conf)
exten => s,n,System(/bin/echo “‘sock=/etc/asterisk/mysql.sock'” >> /etc/asterisk/cdr_mysql.conf)
exten => s,n,System(/bin/echo “‘userfield=1′” >> /etc/asterisk/cdr_mysql.conf)
exten => s,n,Wait(1)
exten => s,n,System(asterisk -r -x “reload cdr_addon_mysql.so”)
Improvements and Explanations
The initial connection will still fail, however the connection macro can be modified to try to connect to the backup database. You will have to be wary of loops.
April 7, 2023
Phone System 