Manage/Edit the Core Dump configuration of an ESXi host

As part of the VCAP6 – DCV we are going to perform Objective 1.1 Configure Dump Collector service

For the complete VCAP – DCV Checklist visit Checklist

What is Core Dump?

Core dump is diagnostic information being captured during purple screen error or a host failure. The core Dump resides in a Diagnostic partition and in-order to create a partition we require atleast 100 MB of free space either locally or remotely available disks.

Coredump partition limitations

  • It cannot be created on an iSCSI LUN (Both hardware and software) and No FCoE LUN.
  • Diagnostic partiions cannot be create using vCLI however the existing partitions can be activated.

    To view the core dump partition from your ESXi host execute below command from the ESXi CLI.

    esxcli system coredump partition get

Core Dump Collector Facts

  • Coredump Server service works on UDP Port (1025-9999) and uses port 6500 as default.
  • Coredump Repository maximum size 10 GB and the default CoreDump Repository size is 2 GB.
  • Network dump collector will not work if the management vmkernel port has been configured to use Etherchanel/LACP
  • The netdump protocol is used for sending coredumps from failed ESXi to the Dump collector service.
  • CoreDump collector only supports IPV4.
  • The network traffic is not encrypted and no authentication mechanism to make sure the integrity and validity of the data being received by the Dump Collector Service.

First two default values can be changed under the Settings of VMware vSphere ESXi Dump Collector Service. More customization can be done by editing the configuration file which will be discussed below.

In-order to enable the CoreDump Service follow the below steps.

  1. Click on Administration>System Configuration under Deployment >Objects>Services

This will list the services associated with VCenter Server. ESXi Dump Collector service will be disabled by default so we will enable it here.

  1. Right click on the “VMware vSphere ESXi Dump Collector” service and click on “Edit Startup Type”
  2. Now select the option “Automatic” as below and start the service.

  3. Configure the ESXi to use the ESXi Dump collector service.

    esxcli system coredump network set –interface-name vmk0 –server-ip –server-port 6500

To list all the network interface details

esxcli network ip interface ipv4 get

  1. Enable ESXi Dump Collector

    esxcli system coredump network set –enable true

Also execute below command to see the coredump configuration settings.

esxcli system coredump network get

    1. Now to verify the settings execute the below command.

      esxcli system coredump network check

      To perform the same using a host profile setup follow the below settings. (I am using my existing host profile)

      How to locate the Dump Collector Folder in VCenter 6?

      The core dump folder can be location under below path.


      If you open netdump-setup.xml file with notepad it will have information about all the default paths as below. These settings can be very well edited and configured according to our requirement. Once the changes are done on the file it is important that the Dump Collector services should be restarted.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.