NVIDIA BMC is based on the OpenBMC open-software framework which builds a complete Linux image for a board management controller (BMC). It uses the Yocto project as the underlying building and distro generation framework.
The primary software components of BMC are the following:
U-boot bootloader
Linux kernel
OpenBMC distro
There is a software version for each of the BMC software components. You may retrieve this information by running the following for each component:
U-boot version – version command from the u-boot prompt
Linux version – uname -a command from the Linux prompt
OpenBMC version – cat /etc/os-release from the Linux prompt
BMC starts booting through u-boot bootloader once the power supply is powered on.
By default, the BMC automatically boots into Linux. To stop at the u-boot prompt, users must type the password 0penBmc (note the use of the digit zero in 0pen) within 5 seconds. To boot Linux from the u-boot prompt, type boot.
The default password for the root user, to be typed in once Linux is booted, is 0penBmc.
ImportantThe default global password is set to expire upon first login. A new password must be configured according to the following policy:
Minimum length: 13
Minimum upper case characters: 1
Minimum lower case characters: 1
Minimum digits: 1
Note that the root account locks after four consecutive failed attempts and automatically unlocks after 10 minutes.
The BlueField platform BMC uses Flattened Image Tree (FIT) format for its Linux kernel.
The output from u-boot's imls command shows the configurations within the FIT image. By default, u-boot has bootcmd_string=bootm 0x20070000 configured and there is no configuration ID used to boot configuration 1 or 2 of the FIT image. So, by default, the BlueField platform BMC boots using BlueField 1U Reference Platform DTB file.
To boot the BMC using the BlueField 2U Reference Platform DTB, do one of two things from the u-boot command line:
For a one-time boot of the platform, run:
bootm 0x20070000#conf@aspeed-bmc-mlx-bluewhale2u.dtb
For persistent boot of the 2U reference platform, modify the environmental variable bootcmd_string:
setenv bootcmd_string bootm 0x20070000#conf@aspeed-bmc-mlx-bluewhale2u.dtb saveenv boot
The supported user management commands are listed in the following table.
No. | Function | Command |
1 | List the users |
For example:
|
2 | User creation |
For example:
|
3 | Set user password |
For example:
Password policy:
|
4 | Enable user |
For example:
|
5 | Disable user |
For example:
|
6 | Set user privilege |
Where "privilege level":
For example:
|
7 | Enable remote IPMI command functionality for user |
For example:
|
8 | Lanplus commands to execute IPMI commands remotely for users with admin permissions |
For example:
|
9 | Lanplus commands to execute IPMI commands remotely for users with other than administrator roles |
For example:
|
10 | Delete user |
For example:
|
The BMC MAC address is derived from the DPU's base MAC with +2 offset. For example:
Base MAC | B8:CE:F6:F7:FF:8C |
BMC MAC | B8:CE:F6:F7:FF:8E |
BMC management network interface can be configured using IPMI. By default, BMC comes up with the DHCP network configuration.
Network configuration functions:
Setting DHCP/Static network mode configuration
Adding/setting IPv4/IPv6 configuration including IP address, gateway, netmask
Adding DNS servers
Adding NTP server
Setting BMC time with NTP server or system RTC
The following table lists the available network IPMI commands:
No. | Function | Command | Description |
1 | Change mode to Static |
For example:
| Sets LAN channel 1 IP config mode to static which corresponds to network interface "eth0" |
2 | Change mode to DHCP |
For example:
| Sets LAN channel 1 IP config mode to DHCP which corresponds to the network interface "eth0" |
3 | Add IPv4 address |
| Adds IPv4 address, default gateway, and netmask to the network interface "eth0" |
4 | Get IPv4 config |
| Gets IPv4 network config for channel 1 which corresponds to the network interface "eth0" |
5 | Set IPv6 address |
| Adds IPv6 address to the network interface "eth0" |
6 | Get IPv6 config |
| Gets IPv6 network config for channel 1 which corresponds to the network interface "eth0" |
7 | Get DNS server |
Output:
Corresponds to: 10.15.12.67 | Gets the DNS server |
8 | Add DNS server |
Output:
Corresponds to: 10.15.12.67 | Adds the DNS server |
9 | Get NTP server |
Output:
Where:
| Gets NTP server |
10 | Add NTP server |
Where:
| Adds NTP server |
11 | Enable time sync to NTP server |
Where:
| Enables NTP time sync |
12 | Enable time sync to system RTC |
Where:
| Disables NTP time sync |
Run the following IPMI command to factory reset the BMC configuration.
ipmitool raw 0x32 0x66
After issuing the ipmitool raw command for factory reset, you must log into the BMC and reboot it for the factory reset to take effect.
If you have lost your BMC login credentials and cannot login, you may issue the following command from the BlueField Arm:
ipmitool mc reset cold
Factory reset also sets the global password for the root user back to its default (0penBmc). Upon first boot following factory reset, make sure to reconfigure the default global password to prevent potential malicious attackers from hacking your system.
Be sure to follow this password policy:
Minimum length: 13
Minimum upper case characters: 1
Minimum lower case characters: 1
Minimum digits: 1
Note that the root account locks after four consecutive failed attempts and automatically unlocks after 10 minutes.
Firmware upgrade of BMC and CEC components using BMC can be performed from a remote server using openbmctool.
The following table presents the commands available to perform the upgrade:
No. | Function | Command | Description |
1 | Trigger a BMC secure update |
Where:
| Triggers BMC secure update |
2 | Track a BMC firmware update |
Where:
| Tracks the BMC firmware update |
3 | Fetch running BMC firmware version |
Where:
| Fetches the running firmware version from BMC |
4 | Reset/reboot a BMC |
Where:
| Reboots/resets the BMC |
5 | Trigger a CEC secure update |
Where:
| Triggers CEC secure update |
6 | Track a CEC firmware update |
Where:
| Tracks the CEC firmware update |
7 | Trigger CEC attestation/challenge-response |
Where:
For example:
In the above example the hex string represents the 32-byte decimal number "1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32". | Triggers CEC attestation or challenge-response |
BMC Update
The command in line #2 in the table above can be used to track the BMC firmware update. The following example shows the completion the first stage of BMC secure update.
python3 openbmctool.py -H <ip_address> -U <username> -P <password> task status -i <task-id>
Attempting login...
Task Details:
TaskState="Completed"
TaskStatus="OK"
TaskProgress="100"
User root has been logged out
BMC reboot is required to complete the BMC secure update operation. BMC reboot can be triggered after the completion of the first stage of BMC secure update operation.
CEC Update
The command in line #6 in the table above can be used to track the CEC firmware update. The following example shows the completion of the first stage of CEC secure update:
python3 openbmctool.py -H <bmc_ip> -U <username> -P <password> apfirmware status cec
Firmware update status for the component cec as below.
TaskState=Frimware update succeeded.
TaskStatus=OK
TaskProgress=100
Power-cycle/cold reset is required to complete the CEC secure update operation. Power-cycle/cold reset can be triggered after the completion of the first stage of CEC secure update operation.