View Xsan logs in macOS Server
You can use the Logs pane of the Server app to view the informational and diagnostic messages that Xsan writes to the SAN logs.
Fibre Channel connection failures or errors are recorded in the system log.
View the SAN logs
In the Logs pane of the Server app , use the Log pop-up menus to choose system log or service log.
To display entries containing a specific name, time, or other text, type in the Search field in the lower-right corner of the window.
From the command line
To see the log for a volume from the command line, look at the log file /Library/Logs/Xsan/data/volume/log/cvlog.
The port mapper process log is in /Library/Logs/Xsan/debug/nssdbg.out.
The system log is in /var/log/system.log.