ESXi on SD Card
Ohhh ESXi on SD cards, it got a little controversial but we managed to keep you, doing the latest install I was greet with the nice warning “No coredump target has been configured. Host core dumps cannot be saved.”
What does this mean you might ask. Well in short, if there ever was a problem with the host, log files to determine what happened wouldn’t be available. So it’s a pick your poison kinda deal.
Store logs and possibly burn out the SD/USB drive storage, which isn’t good at that sort of thing, or point it somewhere else. Here’s a nice post covering the same problem and the comments are interesting.
Dan states “Interesting solution as I too faced this issue. I didn’t know that saving coredump files to an iSCSI disk is not supported. Can you please provide your source for this information. I didn’t want to send that many writes to an SD card as they have a limited number (all be it a very large number) of read/writes before failure. I set the advanced system setting, Syslog.global.logDir to point to an iSCSI mounted volume. This solution has been working for me for going on 6 years now. Thanks for the article.”
with the OP responding “Hi Dan, you can definately point it to an iscsi target however it is not supported. Please check this KB article: https://kb.vmware.com/s/article/2004299 a quarter of the way down you will see ‘Note: Configuring a remote device using the ESXi host software iSCSI initiator is not supported.’”
Options
Option 1 – Allow Core Dumps on USB
Much like the source I mentioned above: VMware ESXi 7 No Coredump Target Has Been Configured. (sysadmintutorials.com)
Edit the boot options to allow Core Dumps to be saved on USB/SD devices.
Option 2 – Set Syslog.global.logDir
You may have some other local storage available, in that case set the variable above to that local or shared storage (shared storge being “unsupported”).
Option 3 – Configure Network Coredump
As mentioned by Thor – “Apparently the “supported” method is to configure a network coredump target instead rather than the unsupported iSCSI/NFS method: https://kb.vmware.com/s/article/74537”
Option 4 – Disable the notification.
As stated by Clay – ”
The environment that does not have Core Dump Configured will receive an Alarm as “Configuration Issues :- No Coredump Target has been Configured Host Core Dumps Cannot be Saved Error”.
In the scenarios where the Core Dump partition is not configured and is not needed in the specific environment, you can suppress the Informational Alarm message, following the below steps,
Select the ESXi Host >
Click Configuration > Advanced Settings
Search for UserVars.SuppressCoredumpWarning
Then locate the string and and enter 1 as the value
The changes takes effect immediately and will suppress the alarm message.
To extract contents from the VMKcore diagnostic partition after a purple screen error, see Collecting diagnostic information from an ESX or ESXi host that experiences a purple diagnostic screen (1004128).”
Summary
In my case it’s a home lab, I wasn’t too concerned so I followed Option 4, then simply disabled file core dumps following the second steps in Permanently disable ESXi coredump file (vmware.com)
Note* Option 2 was still required to get rid of another message: System logs are stored on non-persistent storage (2032823) (vmware.com)
Not sure, but maybe still helps with I/O to disable coredumps. Will update again if new news arises.