Run pre/post checks with the Cluster Verification Utility (cluvfy)

Command

# Full check after a Grid installation/change:
cluvfy stage -post crsinst -n all -verbose
# Before adding a node:
cluvfy stage -pre nodeadd -n <new_node> -verbose
# Component checks:
cluvfy comp nodecon -n all -verbose
cluvfy comp clocksync -n all -verbose
cluvfy comp ocr -n all -verbose
cluvfy comp asm -n all -verbose
# Report only failed checks:
cluvfy stage -post crsinst -n all -verbose | grep -iE "failed|warning"

What it does

Validates network connectivity, clock synchronization, OCR, ASM, user equivalence and OS prerequisites on all nodes; reports problems with suggested fixes.

When to use it

Before and after Grid installation, node addition and upgrades; as a baseline validation for unexplained cluster problems.

Caution

Read-only, but it connects to all nodes over ssh; the grid user needs ssh equivalence. Do not run the -fixup scripts (root) without reviewing them; they change OS parameters.