ESXi host systems can be configured to dump the vmkernel memory to a network server rather than local disk, this is useful in situations where the ESXi host system does not have a local disk or is an auto deployed ESXi host system. During the critical failure on an ESXi host system, the panic routine attempts to write a core dump using either or both the DiskDump (local disk) or NetDump (Dump Collector) mechanism. If NetDump has been configured, the ESXi host system opens a connection from the VMkernel network to the remote IP address of the vSphere ESXi Dump Collector on UDP service port 6500 and transmits a compressed core dump.
To install the vSphere ESXi Dump Collector launch the vSphere installation media and select vSphere ESXi Dump Collector to install from the VMware vCenter Support Tools section and follow the below steps:
1) Specify the vSphere ESXi Dump Collector installation and repository location and the repository maximum size and select Next.
2) Specify the installation type for the vSphere ESXi Dump Collector, in this example we will be specifying a VMware vCenter Server installation and select Next.
3) Specify the vCenter Server address and login credential information and select Next.
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4) Specify the vSphere ESXi Dump Collector port settings and select Next.
5) Specify the vSphere ESXi Dump Collector identification name on the network and select Next.
6) Select Install.
Now that we have installed and configured the vSphere ESXi Dump Collector we now are required to configure the ESXi host system using the esxcli system coredump namespace to use the Network Dump Collector for their core dumps.
1) Connect to the ESXi host system using a SSH client.
2) Verify connectivity on UDP service port 6500 to the Network Dump Collector.
nc -uz deanvc1.dean.local 6500 Connection to deanvc1.dean.local 6500 port [udp/*] succeeded!
3) Configure the Network Dump Collector using the esxcli system coredump namespace.
esxcli system coredump network set --interface-name vmk0 --server-ipv4 192.168.112.89 --server-port 6500
4) Finallly, we need to enable the Network Dump Collector.
esxcli system coredump network set --enable true
Once configured, the vSphere ESXi Dump Collector will store dump files in the directory ‘C:\ProgramData\VMware\VMware ESXi Dump Collector\Data’
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