Odbc connection pool

Hi. I use Asterisk 11.18.0
It is my res_odbcg.conf

enabled => yes
dsn => asterisk-connector
username => user_xxx
password => pass_xxx
pooling => yes
limit => 20
pre-connect => yes
appsrv01*CLI> odbc show

ODBC DSN Settings

  Name:   asteriskdb
  DSN:    asterisk-connector
    Last connection attempt: 1970-01-01 04:00:00
  Pooled: Yes
  Limit:  20
  Connections in use: 1
    - Connection 1: connected

Why asterisk use only 1 connection? I try simultanasly call to asterisk but aasterisk yet use only 1 connection.

You are using an old unsupported version of Asterisk, it may not have fully supported connection pooling as you’d want/expect. The latest versions when used with a recent version of UnixODBC do support it.