# mco_HA_start

This function is called on the master and replica sides before database creation/connection to initialize the HA subsystem.

### For an overview see page HA Applications

### Prototype

        MCO_RET	mco_HA_start ()

### Arguments

void | No arguments

### Description

This function initializes the HA subsystem. It must be called on the master and replica sides before database(s) creation. For shared-memory applications it must be called for each process

### Return Codes

MCO_S_OK | The HA runtime was initialized successfully
MCO_E_EVAL | The eval version of HA (mcoha library) is being used with non-eval version of the runtime (mcolib library)