Configuring the Network Dump Collector service in vSphere

Products

• VMware vCenter Server
• VMware vSphere ESXi
• VMware Cloud Foundation

Issue/Introduction

This article provides methods for configuring the network coredump collector services in vSphere ESXi Server/VMware vCenter Server.

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

Environment

VMware vSphere ESXi 7.x
VMware vSphere ESXi 8.x
VMware vCenter Server 7.x
VMware vCenter Server 8.x

Resolution

The VMware ESXi Dump Collector is packaged with vCenter Server. The configurable options include:

• Directory for storing received coredumps
• Amount of disk space used for storing received coredumps
• Listening network UDP port number

VMware ESXi Dump Collector in the vCenter Server Virtual Appliance

The vCenter Server Virtual Appliance has a pre-configured Netdump service available and running. The directory used for storing received core dumps, the amount of disk space used, and the listening port number are all set to defaults, but can be changed later.

Enabling VMware vSphere ESXi Dump Collector using the VMware vCenter Server Virtual Appliance Web interface

1. Open a web browser, and connect to https://vCenterServerVirtualApplianceHostnameOrIP:5480/.
2. Log in using root account.
3. Click the Services tab.
4. Click the VMware vSphere ESXi Dump Collector service and click on start .
5. Edit the startup type of VMware vSphere ESXi Dump Collector service to automatic if needed.

Configuring the ESXi Dump Collector using the VMware vCenter Server Virtual Appliance command line

1. Open the console of the vCenter Server Virtual Appliance.
2. Log in using an administrative account.
3. Open the /etc/sysconfig/netdumper configuration file using a text editor. The default configuration appears similar to:
   
   NETDUMPER_DIR="/var/core/netdumps"
   NETDUMPER_DIR_MAX_GB=2
   NETDUMPER_PORT=6500
   
   
4. Change the directory used for storing received coredumps.
5. Change the listening UDP port number to the desired value.
6. Change the maximum amount of disk space used for storing received coredumps to a different value, as required. The value is specified in gigabytes.
7. To enable verbose logging, modify the NETDUMPER_OPTIONS line to:
   
   NETDUMPER_OPTIONS="-n -v -d ${NETDUMPER_DIR} -o ${NETDUMPER_PORT}"
   
   
8. Save the /etc/sysconfig/netdumper configuration file.
9. Restart the VMware ESXi Dump Collector service using the command:
   
   service-control --restart vmware-netdumper
   
   
10. The VMware ESXi Dump Collector service startup type can be changed to automatic depending on the use case as the default startup type is manual.
    
    /usr/lib/vmware-vmon/vmon-cli -U netdumper -S AUTOMATIC

Configure ESXi Dump Collector with ESXCLI

1. Set up an ESXi system to use ESXi Dump Collector by running esxcli system coredump in the local ESXi shell.
   
   esxcli system coredump network set --interface-name vmk0 --server-ipv4 xxx.xxx.xxx.xxx --server-port 6500
   
   Note: You must specify a VMkernel NIC and the IP address of the vCenter Server and optional port of the server to which to send the core dumps. 
   
   
2. Enable ESXi Dump Collector:
   
   esxcli system coredump network set --enable true
   
   
3. Check that ESXi Dump Collector is configured correctly:
   
   esxcli system coredump network get

Note :  Ensure that the specified VMkernel interface (vmk0 in this case) has network connectivity to the destination server (e.g., vCenter or the core dump collector) where the core dumps are intended to be stored.

To test network connectivity Use vmkping to test connectivity from a specific VMkernel interface :

vmkping -I vmk0 <destination-IP>

Where destination IP is  IP of destination server (e.g., vCenter or the core dump collector)