VSAN-Troubleshooting-Reference-Manual

Diagnostics and Troubleshooting Reference Manual – Virtual SAN
Similarly, detailed information about the LLOG internals would be needed to
understand the metrics displayed in the LLOG charts, shown here.
If the device is an SSD, and these full graphs of device level stats are chosen, then
additional charts related to LLOG (Logical LOG) are displayed. LLOG is a property of
SSD, and will not be visible in a physical view of a magnetic disk.
One important point to note about the Logical LOG is that upon every ESXi host boot,
LSOM needs to perform an SSD log recovery. This is why rebooting ESXi hosts can
take significantly longer with VSAN enabled. The entire log needs to be read in order
to make sure in-memory state is up to date.
Once again, the full graphs in this view go deep into Virtual SAN internals, and are
typically only of use to VMware Global Support and engineering organizations.
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