Interface Card Critical Resource Analysis(CRA) Whitepaper for HP-UX 11i v3

stop the SG cluster service, a different quorum disk can be configured using an alternative healthy

card and the required olrad operation can be performed.

Scenario 10

System Configuration:

HP-UX OS running in Service Guard (SG) cluster environment with common

lock disk between the cluster nodes, and the cluster is configured with a common lock disk using path

dependent device special file.

Operation Performed:

# rmsf -L

Criticality reported by CRA:

CRA_SYSTEM_CRITICAL

Explanation and user action required:

The above rmsf operation will render the quorum disk unavailable if the requested operation is

allowed to proceed. Since this will result in the node being evicted from the cluster and because the

proper functioning of the SG cluster is considered one of the critical configurations, the above

requested operation will not be allowed by CRA to proceed and the operation will fail with a

CRA_SYSTEM_CRITICAL error.

If the quorum disk has been configured using path dependent device special file, it will not be

possible to provide an alternative path to the quorum disk without losing the SG cluster functionality

and hence the requested operation is not recommended.

However, if the user is prepared to stop the SG cluster service, a quorum disk can be configured

using path-independent DSF, which has one or more lunpaths to the quorum disk and the above

operation can be performed.

Scenario 11

System Configuration:

HP-UX OS running in Service Guard (SG) cluster environment with common

lock disk between the cluster nodes, and the cluster is configured with a common lock disk, which has

one or more lunpath(s) through I/O cards controlled by the same driver.

Operation Performed:

# kcmodule <interface driver associated with card>=unused

Criticality reported by CRA:

CRA_SYSTEM_CRITICAL

Explanation and user action required:

The above operation will render the quorum disk unavailable if the requested operation is allowed to

proceed. Since this will result in the node being evicted from the cluster and the proper functioning of

the SG cluster is considered as one of the critical configurations, the above requested operation will

not be allowed by CRA to proceed and the operation will fail with CRA_SYSTEM_CRITICAL error.

If this operation must be performed for system administration purposes, then, before performing the

above operation, the user must configure another lunpath to the SG quorum disk through a card

controlled by a different I/O driver. However, this is possible only if the quorum disk has been

configured using path-independent device special file (DSF).

If the quorum disk has been configured using a path dependent device special file, it will not be

possible to provide any alternative path to the quorum disk without losing the SG cluster functionality

and hence the requested operation is not recommended to be performed. However, if the user is

prepared to stop the SG cluster, and an alternative path to the quorum disk can be configured

through a card controlled by different I/O driver, then the required operation can be performed.