Every OS that has it's own UIM Robot installation should have a category in the UMP/USM under the built-in Operating Systems group. Since the AS400 (iSeries) OS has it's own unique Robot installation, it should have it's own OS listing, but it doesn't & CA has suggested putting the IDEA for this to be added:
You can see in the CA_UIM database table that if you run:
select * from CM_COMPUTER_SYSTEM where os_description = 'AS400'
you will get:
When the AS400 Robot registers, they only add AS400 to the OS_DESCRIPTION field, but they don't have anything for fields: OS_TYPE, OS_NAME, or OS_VERSION.
This seems like a simple fix for something that was probably just an oversight...