Configuring an ESXi 5.x host to capture a VMkernel coredump from a purple diagnostic screen via the Network Dump Collector

Products

VMware vSphere ESXi

Issue/Introduction

This article provides methods for configuring the network coredump feature in vSphere ESXi 5.x. For more information on the network coredump functionality, see ESXi Network Dump Collector in VMware vSphere 5.x/6.0 (1032051). For more information on configuring a network dump collector to receive diagnostic information, see Configuring the Network Dump Collector service in vSphere 5.0 (2002954).

The network coredump functionality in ESXi allows for capturing diagnostic data via the network in the event of a purple diagnostic screen. For more information, see Interpreting an ESX host purple diagnostic screen (1004250).

Note: A core dump is for diagnostic purposes only. While a core dump may expedite the resolution of hardware issues, it can be performed by a member of our Technical Support Staff if it is deemed necessary.

Symptoms:

Environment

VMware vSphere ESXi 5.1
VMware vSphere ESXi 5.5
VMware vSphere ESXi 5.0

Resolution

The vSphere ESXi 5.x network coredump client can be configuring using esxcli or using Host Profiles. Select a method appropriate to your environment. A host configured using esxcli can be subsequently used as a reference for creating host profiles.

Generally, the host is configured with a VMkernel interface attached to a standard vSwitch which has an active uplink port, and the target netdump server's IP address and port is specified.

Configuring using Host Profiles

Using Host Profiles, you can write a rule to apply the same configuration to a group of hosts. For more information, see the Set Up ESXi Dump Collector from the Host Profiles Interface section of the vSphere Installation and Setup guide. For more information on creating, managing, and applying Host Profiles, see the vSphere Host Profiles guide.

To configure using Host Profiles:

Connect to vCenter Server using the vSphere Client.
Click Home and select Host Profiles.
Create or edit a host profile.
Select Networking Configuration.
Select Network Coredump Settings.
Specify the VMkernel network interface to use for outbound traffic, such as vmk0.
Specify the IP address and UDP port number of the remote network coredump server.
Save and apply the host profile.

Configuring using ESXCLI

The ESXCLI command-line utility allows you to configure an ESXi host locally at the console, or remotely over the network. For more information, see the Configure ESXi Dump Collector with esxcli section of the vSphere Command-Line Interface documentation.

To configure using ESXCLI:

Open a console session to the ESXi host, the vMA, or other location where the vCLI is installed.
Review the current configuration using this command:

esxcli system coredump network get
Specify the VMkernel network interface to use for outbound traffic and the IP address and UDP port number of the remote network coredump server using this command:

esxcli system coredump network set --interface-name <VMkernelInterface> --server-ipv4 <IPAddress> --server-port PortNumber

Example:

esxcli system coredump network set --interface-name vmk0 --server-ipv4 10.11.12.13 --server-port 6500

Note: As of vSphere ESXi 5.1, the VLAN value from the selected interface is used when generated a core dump over the network.
Enable the network coredump configuration using this command:

esxcli system coredump network set --enable true
Review and confirm the configuration using this command:

esxcli system coredump network get
As of vSphere ESXi 5.1, you can also check the functionality of ESXi Dump Collector server configuration by using this command:

esxcli system coredump network check
A successful core dump transmission returns the output:

Verified the configured netdump server is running
To save the configuration file to persist after a reboot, run the command:

/sbin/auto-backup.sh