Use the cluvfy stage -pre crsinst command to check the specified nodes before installing Oracle Clusterware. CVU performs additional checks on OCR and voting disks if you specify the -c and -q options.
cluvfy stage -pre crsinst -n node1,node2 -verbose

Use the cluvfy stage -post crsinst command to check the specified nodes after installing Oracle Clusterware.
cluvfy stage -post crsinst -n node1,node2 -verbose

-- Use the cluvfy stage -post hwos stage verification command to perform network and storage verifications on the specified nodes in the cluster before installing 
   Oracle software. This command also checks for supported storage types and checks each one for sharing.
cluvfy stage -post hwos -n node_list [-s storageID_list] [-verbose]
cluvfy.sh stage -post hwos -n node1,node2 -verbose

-- the cluvfy stage -pre acfscfg command to verify your cluster nodes are set up correctly before configuring Oracle ASM Cluster File System (Oracle ACFS).
cluvfy stage -pre acfscfg -n node_list [-asmdev asm_device_list] [-verbose]
cluvfy stage -pre acfscfg -n node1,node2 -verbose

-- Use the cluvfy stage -post acfscfg to check an existing cluster after you configure Oracle ACFS.
cluvfy stage -post acfscfg -n node_list [-verbose]
cluvfy stage -post acfscfg -n node1,node2 -verbose

-- Use the cluvfy stage -pre cfs stage verification command to verify your cluster nodes are set up correctly before setting up OCFS2 or OCFS for Windows.
cluvfy stage -pre cfs -n node_list -s storageID_list [-verbose]
cluvfy stage -pre cfs -n node1,node2 -verbose

-- Use the cluvfy stage -post cfs stage verification command to perform the appropriate checks on the specified nodes after setting up OCFS2 or OCFS for Windows.
cluvfy stage -post cfs -n node_list -f file_system [-verbose]
cluvfy stage -post cfs -n node1,node2 -verbose

-- Use the cluvfy stage -pre dbcfg command to check the specified nodes before configuring an Oracle RAC database to verify whether your system meets all of the
   criteria for creating a database or for making a database configuration change.
cluvfy stage -pre dbcfg -n node_list -d Oracle_home [-fixup [-fixupdir fixup_dir]] [-verbose]
cluvfy stage -pre dbcfg -n node1,node2 -d Oracle_home -verbose

-- Use the cluvfy stage -pre dbinst command to check the specified nodes before installing or creating an Oracle RAC database to verify that your system meets all of
   the criteria for installing or creating an Oracle RAC database.
cluvfy stage -pre dbinst -n node_list [-r {10gR1 | 10gR2 | 11gR1 | 11gR2}]  [-osdba osdba_group] [-d Oracle_home] [-fixup [-fixupdir fixup_dir] [-verbose]

-- Use the cluvfy stage -pre hacfg command to check a local node before configuring Oracle Restart.
cluvfy stage -pre hacfg [-osdba osdba_group] [-orainv orainventory_group] [-fixup [-fixupdir fixup_dir]] [-verbose]
cluvfy stage -pre hacfg -verbose

-- Use the cluvfy stage -post hacfg command to check the local node after configuring Oracle Restart.
cluvfy stage -post hacfg [-verbose]
cluvfy stage -post hacfg -verbose

/*Use the cluvfy stage -pre nodeadd command to verify the specified nodes are configured correctly before adding them to your existing cluster, and to verify the integrity of the cluster before you add the nodes.

This command verifies that the system configuration, such as the operating system version, software patches, packages, and kernel parameters, for the nodes that you want to add, is compatible with the existing cluster nodes, and that the clusterware is successfully operating on the existing nodes. Run this node on any node of the existing cluster.
*/
cluvfy stage -pre nodeadd -n node_list [-vip vip_list]  [-fixup [-fixupdir fixup_dir]] [-verbose]
cluvfy stage -pre nodeadd -n node1,node2 -verbose

/*
Use the cluvfy stage -post nodeadd command to verify that the specified nodes have been successfully added to the cluster at the network, shared storage, and clusterware levels.
*/
cluvfy stage -post nodeadd -n node_list [-verbose]
cluvfy stage -post nodeadd -n node1,node2 -verbose

/*
Use the cluvfy stage -post nodedel command to verify that specific nodes have been successfully deleted from a cluster. Typically, this command verifies that the node-specific interface configuration details have been removed, the nodes are no longer a part of cluster configuration, and proper Oracle ASM cleanup has been performed.
*/
cluvfy stage -post nodedel -n node_list [-verbose]
cluvfy stage -post nodedel -n node1, node2 -verbose

-- Use the cluvfy comp acfs component verification command to check the integrity of Oracle ASM Cluster File System on all nodes in a cluster.
cluvfy comp acfs [-n [node_list] | [all]] [-f file_system] [-verbose]
cluvfy comp acfs -n node1,node2 -f /acfs/share -verbose

/*
Use the cluvfy comp admprv command to verify user accounts and administrative permissions for installing Oracle Clusterware and Oracle RAC software, and for creating an Oracle RAC database or modifying an Oracle RAC database configuration.
*/
cluvfy comp admprv [-n node_list]
{ -o user_equiv [-sshonly] |
 -o crs_inst [-orainv orainventory_group] |
 -o db_inst [-osdba osdba_group] [-fixup [-fixupdir fixup_dir]] | 
 -o db_config -d oracle_home [-fixup [-fixupdir fixup_dir]] }
 [-verbose]

Use the cluvfy comp asm component verification command to check the integrity of Oracle Automatic Storage Management (Oracle ASM) on all nodes in the cluster. This check ensures that the ASM instances on the specified nodes are running from the same Oracle home and that asmlib, if it exists, has a valid version and ownership.
cluvfy comp asm [-n node_list | all ] [-verbose]
cluvfy comp asm -n node1,node2 -verbose

Use the cluvfy comp cfs component verification command to check the integrity of the clustered file system (OCFS for Windows or OCFS2) you provide using the -f option. CVU checks the sharing of the file system from the nodes in the node list.
cluvfy comp cfs [-n node_list] -f file_system [-verbose]
cluvfy comp cfs -n node1,node2 -f /ocfs2/share -verbose

Use the cluvfy comp clocksync component verification command to clock synchronization across all the nodes in the node list. CVU verifies a time synchronization service is running (Oracle Cluster Time Synchronization Service (CTSS) or Network Time Protocol (NTP)), that each node is using the same reference server for clock synchronization, and that the time offset for each node is within permissible limits.
cluvfy comp clocksync [-noctss] [-n node_list [all]] [-verbose]
cluvfy comp clocksync [-noctss] [-n node_list [all]] [-verbose]

-noctss
If you specify this option, then CVU does not perform a check on CTSS. Instead, CVU checks the platform's native time synchronization service, such as NTP.

Use the cluvfy comp clu component verification command to check the integrity of the cluster on all the nodes in the node list.
cluvfy comp clu [-n node_list] [-verbose]
cluvfy comp clu -n node1,node2 -verbose

Use the cluvfy comp clumgr component verification command to check the integrity of cluster manager subcomponent, or Oracle Cluster Synchronization Services (CSS), on all the nodes in the node list.
cluvfy comp clumgr [-n node_list] [-verbose]
cluvfy comp clumgr -n node1, node2 -verbose

Run the cluvfy comp crs component verification command to check the integrity of the Cluster Ready Services (CRS) daemon on the specified nodes.
cluvfy comp crs [-n node_list] [-verbose]
cluvfy comp crs -n node1, node2 -verbose

Starting with Oracle Database 11g release 2 (11.2.0.2), use the cluvfy comp dhcp component verification command to verify that the DHCP server exists on the network and is capable of providing a required number of IP addresses. This verification also verifies the response time for the DHCP server. You must run this command as root.
# cluvfy comp dhcp -clustername cluster_name [-vipresname vip_resource_name] [-port dhcp_port] [-n node_list] [-verbose]

-clustername cluster_name
The name of the cluster of which you want to check the integrity of DHCP.

-vipresname vip_resource_name
The name of the VIP resource.

-port dhcp_port
The port on which DHCP listens. The default port is 67.

Starting with Oracle Database 11g release 2 (11.2.0.2), use the cluvfy comp dns component verification command to verify that the Grid Naming Service (GNS) subdomain delegation has been properly set up in the Domain Name Service (DNS) server.
Run cluvfy comp dns -server on one node of the cluster. On each node of the cluster run cluvfy comp dns -client to verify the DNS server setup for the cluster.

Use the cluvfy comp ha component verification command to check the integrity of Oracle Restart on the local node.
cluvfy comp ha [-verbose]
cluvfy comp ha -verbose

Use the cluvfy comp freespace component verification command to check the free space available in the Oracle Clusterware home storage and ensure that there is at least 5% of the total space available. For example, if the total storage is 10GB, then the check ensures that at least 500MB of it is free.
cluvfy comp freespace [-n node_list | all]
cluvfy comp freespace -n node1, node2

Use the cluvfy comp gns component verification command to verify the integrity of the Oracle Grid Naming Service (GNS) on the cluster.
cluvfy comp gns -precrsinst -domain gns_domain -vip gns_vip [-n node_list]  [-verbose]

cluvfy comp gns -postcrsinst [-verbose]

Use the cluvfy comp gpnp component verification command to check the integrity of Grid Plug and Play on all of the nodes in a cluster.
cluvfy comp gpnp [-n node_list] [-verbose]
cluvfy comp gpnp -n node1,node2 -verbose

Use the cluvfy comp healthcheck component verification command to check your Oracle Clusterware and Oracle Database installations for their compliance with mandatory requirements and best practices guidelines, and to ensure that they are functioning properly.
cluvfy comp healthcheck [-collect {cluster|database}] [-db db_unique_name]
 [-bestpractice|-mandatory] [-deviations] [-html] [-save [-savedir directory_path]]

Use the component cluvfy comp nodeapp command to check for the existence of node applications, namely VIP, NETWORK, ONS, and GSD, on all of the specified nodes.
cluvfy comp nodeapp [-n node_list] [-verbose]
cluvfy comp nodeapp -n node1, node2 -verbose

Use the cluvfy comp nodecon component verification command to check the connectivity among the nodes specified in the node list. If you provide an interface list, then CVU checks the connectivity using only the specified interfaces.
cluvfy comp nodecon -n node_list [-i interface_list] [-verbose]
cluvfy comp nodecon -i eth2 -n node1,node2 -verbose
cluvfy comp nodecon -i eth3 -n node1,node2 -verbose

Use the cluvfy comp nodereach component verification command to check the reachability of specified nodes from a source node.
cluvfy comp nodereach -n node_list [-srcnode node] [-verbose]

-srcnode node
The name of the source node from which CVU performs the reachability test. If you do not specify a source node, then the node on which you run the command is used as the source node.

Use the cluvfy comp ocr component verification command to check the integrity of Oracle Cluster Registry (OCR) on all the specified nodes.
cluvfy comp ocr [-n node_list] [-verbose]
cluvfy comp ocr -n node1,node2 -verbose

Use the cluvfy comp ohasd component verification command to check the integrity of the Oracle High Availability Services daemon.
cluvfy comp ohasd [-n node_list] [-verbose]
cluvfy comp ohasd -n node1,node2 -verbose

Use the cluvfy comp olr component verification command to check the integrity of Oracle Local Registry (OLR) on the local node.
cluvfy comp olr [-verbose]
cluvfy comp olr -verbose

Use the cluvfy comp peer component verification command to check the compatibility and properties of the specified nodes against a reference node. You can check compatibility for non-default user group names and for different releases of the Oracle software. This command compares physical attributes, such as memory and swap space, as well as user and group values, kernel settings, and installed operating system packages.
cluvfy comp peer -n node_list [-refnode node]  [-r {10gR1 | 10gR2 | 11gR1 | 11gR2}] [-orainv orainventory_group]  [-osdba osdba_group] [-verbose]

-refnode
The node that CVU uses as a reference for checking compatibility with other nodes. If you do not specify this option, then CVU reports values for all the nodes in the node list.

Use the cluvfy comp scan component verification command to check the Single Client Access Name (SCAN) configuration.
cluvfy comp scan -verbose

Use the cluvfy comp software component verification command to check the files and attributes installed with the Oracle software.
cluvfy comp software [-n node_list] [-d oracle_home] [-r {10gR1 | 10gR2 | 11gR1 | 11gR2}] [-verbose]

Use the cluvfy comp space component verification command to check for free disk space at the location you specify in the -l option on all the specified nodes.
cluvfy comp space [-n node_list] -l storage_location -z disk_space {B | K | M | G} [-verbose]

cluvfy comp space -n all -l /u01/oracle -z 2g -verbose

Use the cluvfy comp ssa component verification command to discover and check the sharing of the specified storage locations. CVU checks sharing for nodes in the node list.
cluvfy comp ssa [-n node_list] [-s storageID_list] [-t {software | data | ocr_vdisk}] [-verbose]

cluvfy comp ssa -n node1,node2 -verbose
cluvfy comp ssa -n node1,node2 -s /dev/sdb

Use the cluvfy comp sys component verification command to check that the minimum system requirements are met for the specified product on all the specified nodes.
cluvfy comp sys [-n node_list] -p {crs | ha | database}  [-r {10gR1 | 10gR2 | 11gR1 | 11gR2}] [-osdba osdba_group]  [-orainv orainventory_group] [-fixup [-fixupdir fixup_dir]] [-verbose]

cluvfy comp sys -n node1,node2 -p crs -verbose
cluvfy comp sys -n node1,node2 -p ha -verbose
cluvfy comp sys -n node1,node2 -p database -verbose

Use the cluvfy comp vdisk component verification command to check the voting disks configuration and the udev settings for the voting disks on all the specified nodes.
cluvfy comp vdisk [-n node_list] [-verbose]
cluvfy comp vdisk -n node1,node2 -verbose

runcluvfy stage -pre crsinst -upgrade -n  -rolling -src_crshome  -dest_crshome  -dest_version  -verbose
runcluvfy stage -pre crsinst -upgrade -n rac1,rac2 -rolling -src_crshome /u01/app/grid/11.2.0.1 -dest_crshome /u01/app/grid/11.2.0.3 -dest_version 11.2.0.4.0 -verbose

Strace the command to get more details
eg: strace -t -f -o clu.trc cluvfy comp olr -verbose
/*
[oracle@rac1 ~]$ strace -t -f -o clu.trc cluvfy comp olr -verbose

Verifying OLR integrity

Checking OLR integrity...

Checking OLR config file...

OLR config file check successful


Checking OLR file attributes...

OLR file check successful


WARNING:
This check does not verify the integrity of the OLR contents. Execute 'ocrcheck -local' as a privileged user to verify the contents of OLR.

OLR integrity check passed

Verification of OLR integrity was successful.
[oracle@rac1 ~]$ ls -ltr clu.trc
-rw-r--r-- 1 oracle oinstall 4206376 Jun 12 01:15 clu.trc
[oracle@rac1 ~]$

*/