OLA/R Overview and Concepts

Planning and Preparation

Planning and Preparation

For the most part SMH prevents you from performing OLA/R procedures that would adversly affect other areas of the server. This section provides you with important information that can help minimize errors or problems when performing OLA/R procedures.

Card CompatibilityOn-Line Addition

When on-line adding an interface card, the first issue that must be resolved is whether the new card is compatible with the system. Each OLA/R-capable PCI slot provides a set amount of power. The replacement card cannot draw more power than is available.

The card must also operate at the slot’s bus frequency. A PCI card must run at any frequency lower than its maximum capability, but a card that could only operate at 33 MHz would not work on a bus running at 66 MHz. rad provides information about the bus frequency and power available at a slot, as well as other slot-related data.

On-Line Replacement

When on-line replacing an interface card, the replacement card must be identical to the card being replaced. This is referred to as like-for-likereplacement and should be adhered to because using a similar but not identical card may cause unpredictable results. For example, a newer version of the target card which is identical in terms of hardware may contain an updated firmware version that could potentially conflict with the current driver.

The PCI specification allows a single physical card to contain more than one function. A single-function SCSI bus adapter can not be replaced by a dual-function adapter, even if the additional function on the card was identical to the original SCSI bus adapter.

When the replacement card is added to the system, the appropriate driver for that card must be configured in the kernel before beginning the operation. SMH ensures the correct driver is present. (In most cases, the replacement card will be the same type as a card already in the system, and this requirement will be automatically met.) If you have any

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Chapter 4