Which of these assumptions is correct?
- you're running Splunk on Windows
- you're running Splunk as LOCAL\SYSTEM
- \fileshare\path1\path2\ is on a Windows server in the same domain as the Splunk server
On Windows, UNC paths are supported on the condition that you run Splunk under a service account that can access domain resources like the share you're accessing.
If however you run Splunk as LOCAL\SYSTEM on Windows, the best I've been able to come up with is using "psexec -s -i cmd.exe" and then "net use y: //fileshare/path/path /user:domain\someuser". Domain resources aren't available to LOCAL\SYSTEM so this as an ugly workaround to make them available as Y: drive while using some non-privileged domain user.
Ah Splunk on Linux has no concept of UNC paths or Windows domains so this will never work.
Best alternative is to mount the Windows share under /mnt/something. You should probably investigate mount -t cifs.