To enable username/password authentication on the queue manager, the changes below need to be made to the queue manager configuration.
NOTE: The CHLAUTH(DISABLED) command below is required to disable the IP address filtering on CLIENT channels that MQ has enabled by default. Disabling CHLAUTH does not disable username/password checks. I suspect this may the cause of your issues.
The commands below are MQ 'runmqsc' commands that need to be executed by an MQ privileged user, like the 'mqm' user.
ALTER QMGR CONNAUTH(USE.PW) CHLAUTH(DISABLED)
ALTER AUTHINFO(USE.PW) +
AUTHTYPE(IDPWOS) +
FAILDLAY(10) +
CHCKLOCL(OPTIONAL) +
CHCKCLNT(REQUIRED)
REFRESH SECURITY TYPE(CONNAUTH)