I have an UEFI program that requires additional files from the same medium it was started from. This works fine when booting from disk or USB; I can get the device path for the program itself by requesting the EFI_DEVICE_PATH_PROTOCOL (as EFI_LOADED_IMAGE_DEVICE_PATH_PROTOCOL) from the handle passed to efi_main, and then I modify the path element at the end to find the other files.
When loading via PXE however, the device path I get only contains the path to the Ethernet adapter and the IP protocol:
PciRoot(0x0)/Pci(0x14,0x0)/Pci(0x0,0x0)/MAC(...,0x1)/IPv4(0.0.0.0)
The handle only has EFI_LOADED_IMAGE_PROTOCOL and EFI_LOADED_IMAGE_DEVICE_PATH_PROTOCOL attached, and the FilePath member of the former is an empty path.
Do I still have an IP configuration at this point, or has this been discarded?
Can I find out where the current executable was loaded from?
Can I otherwise express "relative to the current executable"?
In principle I could also repeat the PXE boot, but the PXE menu might contain multiple TFTP servers for different OS installations, so
Can I recover the "active" PXE menu entry?
Related
The GPS hardware I'm using with my Raspberry Pi, if sent the command $CDCMD,33,1*7C, will report the status of the antenna connection.
I'd like this command to be issued whenever my GPS daemon starts. My current config file at /etc/default/gpsd looks like this:
# Devices gpsd should collect to at boot time.
# They need to be read/writeable, either by user gpsd or the group dialout.
DEVICES="/dev/serial0 /dev/pps0"
# Other options you want to pass to gpsd
GPSD_OPTIONS="-n"
# Automatically hot add/remove USB GPS devices via gpsdctl
USBAUTO="false"
# Start the gpsd daemon automatically at boot time
START_DAEMON="true"
Is there anything I can add to this config file to insert either the antenna command, or the path of a file containing the command?
I've searched all over for documentation for the config file, yet all I can find is example file, nothing that fully documents what options are available for configuration.
Alternatively, if the gpsd daemon is already up and running, and already has control of the serial port used to communicate with the GPS hardware, is there a way to send an NMEA command that gpsd will pass along to the hardware?
The only way I've been able to test this command was to shut down gpsd, then run minicom to issue the command to the hardware directly.
I'm trying to deploy an operating system to a target machine via SCCM.
Unfortunately, there are errors in the deployment process and as a consequence, the target machine has not received the operating system correctly.
In order to ascertain what errors are occurring in the deployment process, I wish to view log file(s) for errors. These errors are invariably located in the SMSTSLog file on the target machine.
In given the fact that the target machine is not booting, how can one copy the SMSTSLog from the target machine onto an external USB key in order to view that log file for various errors on another computer?
Plug in into the target machine the USB key which contains the
task sequence for deployment .
Press F12 (Dell machines) to load the boot options.
If it's a legacy boot then choose the USB Storage which contains the task sequence.
or
If its a UEFI boot then choose UEFI option.
For help in identifying which boot option, look at the memory size of the mounted external memory on the boot list.
If the size listed is similar to the size of your USB stick (e.g. UEFI: Jetflash 2GB) then this is your target USB stick to boot from.
Wait for the files to load from the USB.
When the task sequence launches from the USB stick press F8
to bring up a command prompt. Note: Pressing F8 multiple times launches multiple command prompts.
A Task Sequence Wizard window may appear. Simply move this window to
the side of the screen as you are only interested in bringing up a
command prompt.
It is necessary to identify the label volume for the external USB key.
To do this do the following inside the command prompt:
type: Diskpart
Then type: List Volume
You will see a number of volumes listed.
Look for the volume of type removable (as you should only have one removable USB connected to the machine at this time) and
note its label e.g. D
Press F8 again to bring up another command prompt window.
You will now attempt to copy the log file with the following command:
xcopy [source] [destination]
E.g. Type: xcopy X:\windows\temp\SMSTSLog*.* D:\
Source is: X:\windows\temp\SMSTSLog*.*
Destination is: D:\
Then simply remove the USB stick and open in another machine to view SMSTSLog with your editor of choice.
Colleagues and users testing various features in a program use MFDeploy to install for example "MyApp.exe" onto their Netduino +2. This method works great. Is there a way to also MFDeploy a "MyApp.config" text file so they can set their specific network criteria (like Port#) or other program preferences? Obviously, more robust preferences can be set from desktop software or web app AFTER the connection is established.
After several days researching, I could not find a viable means of transferring a config file via MFDeploy. Decided to add a "/install" command line option to the desktop app:
cncBuddyUI.exe [/help|/?] [/reset] [/discover] [/install:[axisA=X|Y] ,port=9999]]
/help|/? Show this help/usage information
/reset Create new default software configuration
/discover Listen for cncBuddyCAM broadcasting IPAddress & Port (timeout 30 secs)
/install Install hardware specific settings on Netduino+2 SDCard.
port Network port number (default=80)
axisA Slave axisA motor signals to X or Y axis
During "/install" mode, once cncBuddyCAM (Netduino app) network connects to cncBuddyUI (desktop app), the configuration parameters are transmitted and written onto the SDCard (\SD\config.txt).
Every warm boot now reads \SD\config.txt at startup and loads the configuration parameters into the appropriate application variables.
After several weeks of usage, I find this method preferable and easier to customize. Check out cncBuddy on Github.
I am learning to write character device drivers from the Kernel Module Programming Guide, and used mknod to create a node in /dev to talk to my driver.
However, I cannot find any obvious way to remove it, after checking the manpage and observing that rmnod is a non-existent command.
What is the correct way to reverse the effect of mknod, and safely remove the node created in /dev?
The correct command is just rm :)
A device node created by mknod is just a file that contains a device major and minor number. When you access that file the first time, Linux looks for a driver that advertises that major/minor and loads it. Your driver then handles all I/O with that file.
When you delete a device node, the usual Un*x file behavior aplies: Linux will wait until there are no more references to the file and then it will be deleted from disk.
Your driver doesn't really notice anything of this. Linux does not automatically unload modules. Your driver wil simply no longer receive requests to do anything. But it will be ready in case anybody recreates the device node.
You are probably looking for a function rather than a command. unlink() is the answer. unlink() will remove the file/special file if no process has the file open. If any processes have the file open, then the file will remain until the last file descriptor referring to it is closed. Read more here: http://man7.org/linux/man-pages/man2/unlink.2.html
I have a FinalBuilder job that, as a final step, deploys the compiled app and DLLs to a network share on another server.
About 50% of the time, it just fails with
Win32 Error : The network path was not found
Changing the target from \\myserver\myshare to \\myserver.mydomain.com\myshare will often fix it temporarily - the first 2-3 runs after modifying the build file will work, after which it'll start failing again.
The FinalBuilder task is running with domain credentials granting admin access on the target box; and copying files to/from shares on that server via Windows Explorer works reliably.
I'm completely stumped.
Finally tracked this down. The target server was a virtual machine, and the Hyper-V host network settings were set to "Virtual Network" instead of "Virtual Teamed Network"
I have no idea what that means, but having changed it to Virtual Teamed Network, it works flawlessly. O_o
The network path was not found.
This is related to DNS/WINS not being able to look up the name. When I have seen this there are problems with our DNS servers.
Adding an Entry into the lmhost file would prevent the system from looking in DNS/WINS.
If that does not work, another option to consider is to increase the number of retries on the Action. This can be done from the "Runtime" tab of the action by clicking on "Timing Properties"