Collecting core dumps gives VMware support (and massochists) something to evaluate in the event of an ESXi PSOD. Collecting and viewing ESXi core dumps involves serveral elements- ESXi configuration, collector configuration and a dump viewer.
Collector Configuration
Fortunately, the VMware vCenter Server Appliance can be used to collect crash dumps. Unfortunately, the service can only be configured on the long deprecated Flash client.
Log into the Flash client at https://vcsa01.example.com/vsphere-client/
Head to Home > Administration > System Configuration > Services > VMware vSphere ESXi Dump Collector (vcsa01.example.com) > Actions > Edit Startup Type > Automatic
SSH to the vCSA
Start the dump collector, verify it has started and enter a shell promt
service-control --start vmware-netdumper
service-control --status vmware-netdumper
shell
To customize dump collector service configuration
vi /etc/sysconfig/netdumper
Apply changes
service-control --restart vmware-netdumper
ESXi Configuration
SSH to an ESXi host
esxcli system coredump network set --interface-name vmk0 --server-ipv4 10.0.0.10 --server-port 6500
esxcli system coredump network set --enable true
where `vmk0` is the outgoing interface and `–server-ipv4 address` is core dump server
Viewing Dumps
Following crash, copy crash dump from vCSA to any ESXi host-
Enable SSH on target ESXi host
From the collector, copy dump from collector to an ESXi host
scp /var/core/netdumps/ffff/10/0/0/20/zdump_ffff.10.0.0.20-2021-01-01-14_11-0 [email protected]:/vmfs/volumes/lun001
From the ESXi host, extract the dump file
esxcfg-dumppart -L /vmfs/volumes/lun001/zdump_ffff.10.0.0.20-2021-01-01-14_11-0
Open the dump file
tail -n 250 vmkernel-log.1
