The easiest way would to use GDB found at https://sourceware.org/gdb/
-
Install GDB: Ensure you have GDB installed on your system.
-
Open the Dump File: Use GDB to open the dump file:
gdb -c /local/path/file.dump
-
Analyze the Dump: Use GDB commands to analyze the dump. This requires knowledge of GDB and the internal structure of the ESXi system.
Another way would be to use VMware Dump Collector, however it has many steps to setup and you would have to sent dumps to it. I have not used it with dump files that pre-existed before configuring and installing it.
Steps to Obtain and Install VMware Dump Collector
-
Download vCenter Server Installation Media:
- Go to the VMware Customer Connect portal: VMware Customer Connect
- Log in with your VMware account.
- Navigate to the
Downloads
section.
- Select the version of vCenter Server that matches your ESXi hosts.
- Download the vCenter Server ISO file.
-
Mount the ISO File:
- Mount the ISO file on a Windows machine. You can do this by right-clicking the ISO file and selecting
Mount
.
-
Run the Installer:
- Open the mounted ISO and navigate to the
vCenter-Server\extras\vmware-dump-collector
directory.
- Run the
VMware-Dump-Collector-<version>.exe
installer.
-
Follow the Installation Wizard:
- Follow the prompts in the installation wizard to install the VMware Dump Collector.
- You will need to configure the network settings, including the port on which the Dump Collector will listen (the default is port 6500).
Configure ESXi to Use the Dump Collector
After installing the VMware Dump Collector, you need to configure your ESXi hosts to send dump files to the collector.
-
Access ESXi Host via vSphere Client:
- Open the vSphere Client and connect to your vCenter Server.
-
Navigate to Host Settings:
- Select the ESXi host you want to configure.
- Go to
Configure
> Advanced System Settings
.
-
Modify Dump Collector Settings:
- Find and modify the following settings:
Net.Dump.CollectorHost
: Set this to the IP address or hostname of the machine where the Dump Collector is installed.
Net.Dump.CollectorPort
: Set this to the port number on which the Dump Collector is listening (default is 6500).
Net.Dump.ServerEnabled
: Set this to 1
to enable sending dumps to the Dump Collector.
-
Save Settings and Reboot:
- Save the changes and reboot the ESXi host for the settings to take effect.
Verify Configuration
-
Check Dump Collector Status:
- On the machine where the Dump Collector is installed, ensure that the VMware Dump Collector service is running. You can check this in the Windows Services management console (
services.msc
).
-
Test Configuration:
- You can test the configuration by manually generating a core dump on the ESXi host and verifying that it is received by the Dump Collector.
------------------------------
Love for Virtual Infrastructure!
Please mark as Recommended if this solved your problem. This will help the community find solutions to their problems as well.
More Logs, More Info, More Screenshots = Easier To Help You
------------------------------------------------------------
VCP-DCV 8.x | VCP-DCV 6.x | CompTIA A+, Net+, Sec+, Proj+, Server+ | MCSE | MCSA | MCITP
------------------------------
Original Message:
Sent: Jun 11, 2024 09:33 AM
From: nsousaarlington
Subject: .dumpfile Debugging
Hi Casey, thanks for the response.
Is there a way to debug these files:

Is there any sensitive info in these dumpfiles? Can these be encrypted or not encrypted based on an ESXi host setting?
Original Message:
Sent: Jun 11, 2024 02:58 AM
From: Casey
Subject: .dumpfile Debugging
1) Yes you can extract the dump files when an ESXi host crashes (if that is what you are trying to do).
- The core dump file can be found in the ESXi host's filesystem, usually in the directory
/var/core
or /vmfs/volumes/<datastore>/vmkdump
. - The file typically has a
.dump
or .core
extension and contains detailed information about the state of the system at the time of the crash, including memory contents, CPU state, and active processes. This information is invaluable for VMware support engineers to analyze the root cause of the crash. - If for some reason the files are not located at the mentioned directories, try running
find / | grep .dump
or find / | grep .core
- You might get a ton of results, just a warning.
2) You're correct that the setting shown in the screenshot determines whether core dump files are encrypted. When "Encryption Mode" is enabled, the core dump files generated by the ESXi host are encrypted to prevent unauthorized access to sensitive cryptographic data.
To determine whether a specific core dump file is encrypted or not, you can check the following:
Encryption Mode Setting: As shown in your screenshot, if "Encryption Mode" is enabled, the core dump files will be encrypted. If it is disabled, the core dump files will not be encrypted.
File Inspection: Encrypted core dump files often have a different structure or header compared to non-encrypted files. However, this method requires specific knowledge about the file format and encryption used by VMware.
File Location: If you know the dump file's location and the encryption mode status at the time of the crash, you can infer the encryption status.
If the encryption mode was enabled when the dump file was created, you can be confident that the file is encrypted. Otherwise, it is not encrypted.
------------------------------
Love for Virtual Infrastructure!
Please mark as Recommended if this solved your problem. This will help the community find solutions to their problems as well.
More Logs, More Info, More Screenshots = Easier To Help You
------------------------------------------------------------
VCP-DCV 8.x | VCP-DCV 6.x | CompTIA A+, Net+, Sec+, Proj+, Server+ | MCSE | MCSA | MCITP
Original Message:
Sent: Jun 10, 2024 12:19 PM
From: nsousaarlington
Subject: .dumpfile Debugging
1) Is there a way to extract/debug a *.dumpfile?
2) How do you tell which dumpfiles are encrypted versus not? My understanding is that the dumpfiles are encrypted if this setting is enabled:
