IBM System Storage DS4000, Hardware Maintenance Manual

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The scsiRescan command requests a SCSIrescan to look for new devices. If
channel is specified (1 or 2), then only that channel is scanned. If channel
is not specified or if channel is 0, then all channels are scanned.
Notes:
1. Rescanning a SCSI bus can delay I/O commands pending on that bus
for several seconds. Do not rescan SCSI buses when this delay cannot
be tolerated. If possible, scan only the bus where a new device has been
added.
2. If a channel is specified, that channel is scanned and the prompt is
returned on completion. If no channel is specified (or 0 is specified),
SCSI channels 1 and 2 are scanned in sequence and the prompt is
returned on completion.
3. When a device is discovered, there can be further device specific
initialization that continues after the scan has completed. In this case,
the device might not show up immediately when you issue the
fcShowDevs command. (Tape and changer devices that indicate a
ready status are available after the scan is completed.)
4. If a SCSI target device requires replacement, remove the old device. Set
the new device to the same SCSI bus ID as the old device and attach it
to the same channel. Rescan the channel to update the configuration
data. The new device should be available to host systems with the
same LUN as the old device.
scsiShow
The scsiShow command lists all SCSI channels and the attached devices
for each channel.
Router > scsiShow
SCSI Initiator Channel 1: 0xc195e670
ID LUN Vendor Product Rev | Sync/Off Width
---------------------------|------------
0 0 IBMAS400 DFHSS4W 4545 | 12/15 16 S W Q
SCSI Initiator Channel 2: 0xc0ed3900
ID LUN Vendor Product Rev | Sync/Off Width
---------------------------|------------
4 0 IBM 0357011 5324 | 25/15 16 S W
4 1 IBM 0357011 5324
|
value = 0 = 0x0
Router >
The following list describes the example fields:
ID The SCSI ID of the target device
LUN The SCSI LUN of the target device
Vendor The content of the Vendor ID field from the SCSI inquiry data
Product The content of the Product ID field from the SCSI inquiry data
Rev The content of the Revision ID field from the SCSI inquiry data
Sync/Off The negotiated synchronous transfer period and offset. The
period is the negotiated transfer period. Multiply the period times 4 ns. to
determine the actual period. However, if the period is negotiated to 12,
then 50 ns. is used. The offset indicates the request/acknowledge
(REQ/ACK) offset that was negotiated. A zero in these fields indicates that
asynchronous transfer is in use.
Chapter 14. IBM Storage Area Network Data Gateway Router (2108-R03)
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