Dialogic Voice Cards - Switching Service limitation under Linux

Symptom

An application running on a Dialogic® AG Series Media Board that calls swiOpenSwitch may receive a return code of CTAERR_DRIVER_OPEN_FAILED or ADIERR_CANNOT_CREATE_CHANNEL.

Reason for the issue

Each time an AG  switch is opened under Linux a new channel is created on the board. Due to channel limitations of Linux, this prevents all the channels on a Dialogic® AG 4000 Series Media Board or a Dialogic® AG Quad Media Board being opened. The error ADIERR_CANNOT_CREATE_CHANNEL shows that no more channels can be opened.

Workaround

It is recomended that swiOpenSwitch is called only once for a given board. In the model of one process per port, only one process should be used for switching.
Switching operations should be eliminated in the other processes. For best performance, it is recommended that the cta context used for opening switches is created on a separate cta queue.

This workaround is not sufficient for the AG Quad E1 board. By default the OAM keyword MaxChannels is set 120 . If switching is to be performed on an AG Quad E1 board,  MaxChannels should be set to 124 or 128.