New MariaDB server "limiting" Kamailio CPS - sr-users

31 May 2021

Good afternoon All,

Im hoping for some advise or direction with the below. We are running a Kamailio SBC used
for high call volumes and recently decided to upgrade the Database servers as the existing
servers were struggling. Both the old and new databases are using MariaDB(version details
all below), the problem we face is that since migrating to the new database there appears
to a limitation to the amount of DB connections that can be processed or accepted. The SBC
functions normally until the CPS starts to exceed around 100cps at which point the SBC
stops responding to invites(in bursts which resembles flood prevention). We have checked
both the Kamailio logs and the MySQL logs on the DB, both log files have no indication of
errors that would cause the problem experienced(the logs attached are seen when the SBC is
cut back to use the old DB, not sure they are related to the fault), the
connections/processes in mysql do not drastically increase or get stuck either. The fault
points to a db connection limit of some kind but all users have no limitations set. If
anyone has experienced a similar problem or has any advise it would be greatly
appreciated.

Some info on the Kamialio and DB versions

New DB
root@voice-jhb-db01:~# mysql --version
mysql  Ver 15.1 Distrib 10.3.27-MariaDB, for debian-linux-gnu (x86_64) using readline 5.2

Old DB
[root@isadb01 ~]# mysql --version
mysql  Ver 15.1 Distrib 10.0.36-MariaDB, for Linux (x86_64) using readline 5.1

Kamailio SBC
[root@sbc01 ~]# kamailio -v
version: kamailio 5.1.4 (x86_64/linux)

Kind regards,

Stephen  
Voice Engineer 

 Tel: 
2404 
 Fax: 
3468 
 Email: 