6.5

Table Of Contents
The following considerations apply.
n
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 the vSphere Storage documentation.
n
A standalone host must have a diagnostic partition of 110 MB.
n
If multiple hosts share a diagnostic partition on a SAN LUN, congure a large diagnostic partition that
the hosts share.
n
If a host that uses a shared diagnostic partition fails, reboot the host and extract log les immediately
after the failure. Otherwise, the second host that fails before you collect the diagnostic data of the rst
host might not be able to save the core dump.
Diagnostic Partition Creation
You can use the vSphere Web Client to create the diagnostic partition on a local disk or on a private or
shared SAN LUN. You cannot use vicfg-dumppart to create the diagnostic partition. The SAN LUN can be
set up with FibreChannel or hardware iSCSI. SAN LUNs accessed through a software iSCSI initiator are not
supported.
C 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 les immediately after
the failure.
Diagnostic Partition Management
You can use the vicfg-dumppart or 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 Web 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.
I 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.
Managing Core Dumps
With esxcli system coredump, you can manage local diagnostic partitions or set up core dump on a remote
server in conjunction with the ESXi Dump Collector.
For information about the ESXi Dump Collector, see the vSphere Networking documentation.
Manage Local Core Dumps with ESXCLI
You can use ESXCLI to manage local core dumps.
The following example scenario changes the local diagnostic partition by using ESXCLI. Specify one of the
options listed in “Connection Options for vCLI Host Management Commands,” on page 19 in place of
<conn_options>.
vSphere Command-Line Interface Concepts and Examples
162 VMware, Inc.