When running the Esxcli command, VMWare users may get a warning that says that the core dump target has not been configured, so the host core dumps can not be saved. This issue has been noted after updating the host version. In this post, we will discuss this issue and see what can be done to resolve it.
No coredump target has been configured. Host core dumps cannot be saved
Fix No coredump target has been configured, Host core dumps cannot be saved
If you get No coredump target has been configured, Host core dumps cannot be saved message in VMWare when running the Esxcli command or making some changes to the disk, follow the solutions mentioned below to resolve the issue.
- Create dump files for your ESXi hosts
- Enable coredump on USB and create the partition
- Disable the warning
Let us talk about them in detail.
1] Create dump files for your ESXi hosts
If you use iSCSI storage for your ESXi hosts, including boot from SAN, you must create dump files for them.
First, you have to create an empty dump file using the command mentioned below.
esxcli system coredump file add -d *your_datastore_name* -f *the_dumpfile_name(I use the ESXi hostname)*
Then, configure your newly created file as your active dump file.
esxcli system coredump file set -p /vmfs/volumes/*your_datastore_name*/vmkdump/*the_dumpfile_name*.dumpfile
Finally, run the command mentioned below to confirm your dump file.
esxcli system coredump file list
You will receive an event notifying you that the coredump has been set up and your warning will disappear.
2] Enable coredump on USB and create the partition
If you are using a USB, you need to enable coredump on it and create the partition. To do the same, you need to follow the steps mentioned below.
- First of all, go to the warning, and then to Configure System > Advanced System Settings.
- Now, click on the Edit button and then filter with the keyword VMkernel.Boot.allow and find VMkernel.Boot.allowCoreDumpOnUsb.
- You then have to change the value associated with VMkernel.Boot.allowCoreDumpOnUsb to true.
- Use the command ‘esxcli storage filesystem list’ to find available local storage locations of Type VMFS-L after connecting to the host via SSH.
- Then run the following command.
esxcli system coredump file add -d DATASTORE -f HostName -s 2000
- Run esxcli system coredump file list to confirm if the coredump file has been created.
- If under Active, it says False, run the command – esxcli system coredump file set -s -e=True. It will set it to true.
This will do the job for you. But still, we will try to connect to the host via SSH and search for available storage locations. Follow the steps mentioned below.
- First of all, run the command mentioned below.
esxcli storage filesystem list
- Run the command mentioned below to create the core dump file. Make sure to replace Datastore and HostName in the command mentioned below.
esxcli system coredump file add -d DATASTORE -f HostName -s 2000
- Execute the command to check if the core dump file was created.
esxcli system coredump file list
- Finally, run the command mentioned below to enable the core dump file.
esxcli system coredump file set -s -e=True
Hopefully, this will do the trick for you.
3] Disable the warning
If you don’t like the message that’s displayed, and you want to disable it, just go to ESXi Host > Configuration > Advanced Settings, look for UserVars.SuppressCoredumpWarning, and set its value to 1.
Read: Best Free Crash Dump Analyzer software for Windows
How do I configure core dump on vCenter?
To configure core dump on VCenter, you need to go to Home > Administration > System Configuration > Services and then select the ESXi Dump Collector service and enable it by clicking on the Actions tab. Once you have enabled the coredump service, you can start the service by selecting the option under the Actions menu.
Read: How to change Memory Dump Settings on Windows ?
What is a coredump file VMware?
Core dumps are useful for debugging and analyzing an ESX host that may crash due to kernel panic. You can identify a kernel panic by the occurrence of a purple screen, also known as PSOD (similar to Windows “Blue Screen Of Death”). Starting from VMWare ESX 5.5, users can create core dumps to a file instead of a partition, which provides greater flexibility and convenience.
