Looking at Adapter Installation

Because power to the slot must be off when the old card is removed and the new card is inserted, the effects of shutting down the card's functions must be carefully considered.This is particularly important if there is no on-line failover or backup card to pick up those functions. For example:

A critical resource is one that would cause a system crash or prevent the operation from successfully completing if the resource were temporarily suspended or disconnected. For example, if the SCSI adapter to be replaced connects to the unmirrored root disk or swap space, the system will crash when the card is shut down.

During an OLAR procedure, it is essential to check the targeted card for critical resources, as well as the effects of existing disk mirrors and other situations where a card's functions can be taken over by another card that will not be affected.

Fortunately SAM performs a thorough critical resource analysis automatically, and presents options to you based on its findings. If you determine that critical resources will be affected by the procedure, you should replace the card when the server is off-line.
If you must take action immediately, you can use rad to attempt an on-line addition of a backup card and deletion of the target card.

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 PCI slot provides a set amount of power. The replacement card cannot require 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; however, a card that operated at a maximum of 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.

When on-line replacing an interface card, the replacement card must be identical to the card being replaced or at least be able to operate using the same driver as the replaced card. This is referred to as like-for-like replacement 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 For example, a newer version of the target card which is identical in terms of hardware may contain an updated firmware version that could potentially conflict with the current driver.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 port. A single-port SCSI bus adapter can not be replaced by a dual-port adapter, even if the additional port(s) on the card are 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. SAM 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 question about the driver's presence, or if you are not certain that the replacement card is identical to the existing card, you can use ioscan together with rad to investigate.

The HBA can be online added only if the attribute values of initiator ID and speed are usable in your SCSI configuration. These values will be set to the current PDC values (if any) or be defaulted to the new HBA's values (see Table 2-2 “A5159-60101- Default Attribute Values”).

If these attributes are not acceptable, you must reboot the system to access the BCH prompt and then change the values in the PDC.

The A5159-60101 can be Online Replaced without special considerations. See the Configuring HP-UX Peripherals manual for the steps that are necessary to OLR this HBA.