Device Limits & System Settings

Limits regarding resource usage, such as maximum CPU usage or maximum storage usage, can be specified in different metrics on the /opt/limits/default.json file and can be configured by Device Builders. The resources that can be limited are indicated with the "Limits" json object as described in the Storage statistics section below.

Storage Statistics

To provide a directory that is reported by the Industrial Edge Management (IEM), Device Builders can only specify directories on the /opt/limits/default.json file with the "MonitoredStorage" and "Path" json object.

$ cat /opt/limits/default.json
{
"Limits":
{
   "MaxInstalledApplications":20,
   "MaxRunningApplications":10,
   "MaxMemoryUsageInGB":8.0,
   "MaxStorageUsageInGB":20.0,
   "MaxCpuUsagePerecentage":100
},
"MonitoredStorage":
{
   "Path":"/"
}
}

Firmware Version

To retrieve accurate firmware information from the Operating System via IE Device Kit services, it's essential to include a VARIANT key with a valid value in the /etc/os-release file. If the VARIANT key is absent, no firmware information will be returned when querying from IE Device Kit services.

The VARIANT field is a mandatory field when a firmware update is performed. Not only must the field be present, but it must also contain a valid firmware version information. This information is used during the firmware update process. Without this field or with an empty value, firmware updates may not be executed on the device.

Here's an example of how the content might look:

$ cat /etc/os-release
PRETTY_NAME="Siemens Industrial OS 2.1 (buster)"
NAME="Industrial OS"
VERSION_ID="2.1"
VERSION="2.1 (buster)"
VERSION_CODENAME=buster
ID=industrial-os
HOME_URL="https://www.mentor.com/embedded-software/linux/mel-omni-os/"
SUPPORT_URL="https://www.mentor.com/support"
BUG_REPORT_URL="https://www.mentor.com/support"
VARIANT="ied-os-1.1.0-21-amd64-develop"

System Settings regarding Firmware Update

The Edge Device ID value is required regarding firmware updates. This Edge Device ID is located in the configuration file which is used to onboard the Edge Device. For this reason, this value is written to a file on the Edge Device while the Edge Device is onboarding.

NOTICE

In reference service implementation for Device Builders, the Onboard Service writes the Edge Device ID to /var/device.id while onboarding the Edge Device.

System Settings regarding Log Collection

The Edge Device Name value is required for log collection to ensure unique log names for each Edge Device. This Edge Device Name is located in the configuration file which is used to onboard the Edge Device. For this reason, this value is written to a file on the Edge Device while the Edge Device is onboarding.

NOTICE

In reference service implementation for Device Builders, the Onboard Service writes the Edge Device Name to /var/device.name while onboarding the Edge Device.

System Settings regarding Network Configuration by Label

The LabelMap value is required to relate labels with the network interface name if the network interface is configured by label instead of MAC address. LabelMap is located in the configuration file which is used to onboard the Edge Device. For this reason, this value is written to a file on the Edge Device while the Edge Device is onboarding.

NOTICE

In reference service implementation for Device Builders, the Network Service writes the LabelMap to /var/network.label while onboarding the Edge Device.