Setting this property will change required archiving level for messages for every account on server. User will be able to change this to any lower value by setting default modes as described in XEP-0136 section 2.4 but user will be allowed to set higher archiving level. If this property is set to higher value then default archiving level is set then this setting will be used as default archiving level setting.

Possible values for this setting are the same as values for default archiving level setting, see the section called “Setting default value of archiving level for message on a server” for list of possible values.

To set required level to body you need to set required-store-method of message-archive processor to body:

sess-man {
    message-archive {
        required-store-method = `body`
    }
}