Managing Diagnostic
Partitions
Your host must
have a diagnostic partition, also referred to as dump partition, to store core
dumps for debugging and for use by VMware technical support.
A diagnostic partition is on
the local disk where the
ESXi
software
is installed by default. You can also use a diagnostic partition on a remote
disk shared between multiple hosts. If you want to use a network diagnostic
partition, you can install
ESXi
Dump
Collector and configure the networked partition. See
Manage Core Dumps with ESXi Dump Collector.
The following considerations
apply.
- A diagnostic partition cannot be located on an iSCSI LUN accessed through the software iSCSI or dependent hardware iSCSI adapter. For more information about diagnostic partitions with iSCSI, see General Boot from iSCSI SAN Recommendations in thevSphere Storagedocumentation.
- A standalone host must have a diagnostic partition of 110 MB.
- If multiple hosts share a diagnostic partition on a SAN LUN, configure a large diagnostic partition that the hosts share.
- If a host that uses a shared diagnostic partition fails, reboot the host and extract log files immediately after the failure. Otherwise, the second host that fails before you collect the diagnostic data of the first host might not be able to save the core dump.
Diagnostic Partition
Creation
You can use the
vSphere Client
to create the diagnostic partition on a local disk
or on a private or shared SAN LUN. The SAN LUN can be set up with FibreChannel or
hardware iSCSI. SAN LUNs accessed through a software iSCSI initiator are not
supported. If two
hosts that share a diagnostic partition fail and save core dumps to the same
slot, the core dumps might be lost.
If a host that uses a shared
diagnostic partition fails, reboot the host and extract log files immediately
after the failure.
Diagnostic Partition
Management
You can use the
esxcli system coredump
command to query, set, and scan an ESXi
system's
diagnostic partitions. The vSphere
Storage
documentation explains how to set up diagnostic partitions with
the vSphere Client
and how to
manage diagnostic partitions on a Fibre Channel or hardware iSCSI SAN. Diagnostic partitions can
include, in order of suitability, parallel adapter, block adapter, FC, or
hardware iSCSI partitions. Parallel adapter partitions are most suitable and
hardware iSCSI partitions the least suitable.
When
you list diagnostic partitions, software iSCSI partitions are included.
However, SAN LUNs accessed through a software iSCSI initiator are not supported
as diagnostic partitions.