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prtvtoc Unable to read VTOC in EMC PowerPath environment (Doc ID 1515333.1)

Last updated on OCTOBER 05, 2022

Applies to:

Solaris Operating System - Version 10 10/09 U8 and later
Information in this document applies to any platform.


Execution of /usr/sbin/prtvtoc against a LUN returns "Unable to read VTOC".


There are three different volume label types supported by Solaris:

1. Sun Microsystems, Inc. Volume Table of Contents (SMI VTOC) which supports volume sizes up to 1 TB.

2. Sun Microsystems, Inc. Volume Table of Contents Extended (SMI EXTVTOC). Request For Enhancement 15483957 (Sun CR# 6708609) "support booting on disks > 1TB (phase 1)", released with Patch ID: 141444-09 "SunOS 5.10: kernel patch" and Patch ID: 141445-09 "SunOS 5.10_x86: kernel patch", introduced the concept of SMI extvtoc vs. SMI vtoc, which supports volume sizes up to 2 TB.

3. Extensible Firmware Interface GUID Partition Table (EFI GPT) which supports volumes from 0 to greater than 2 TB. Unfortunately, SPARC OBP could not boot from a volume with an EFI label.

For more information, please reference the Chapter on Managing Disks in the Solaris System Administration Guide: Devices and File Systems at the following:


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