Assign fix sd numbers to drivers

["Georges Heinesch" <geohei-ml%geohei.lu@localhost>]

Since I frequently add and remove drives from the SCSI chain, I would
like to attribute fix SCSI numbers to the different SCSI IDs.

I have an internal A3000 SCSI bus and the CSPPC SCSI bus.

I thought of the following:

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[...]

ahsc0       at mainbus0     # A3000 scsi
scsibus0    at ahsc0
cbiiisc0    at zbus0        # Cyberstorm mk.III/Cyberstorm PPC SCSI
scsibus1    at cbiiisc0

#each hard drive from low target to high
#will configure to the next available sd unit number
# sd*    at scsibus? target ? lun ?  # scsi disks

sd0 at scsibus0 target 0 lun 0
sd1 at scsibus0 target 1 lun 0
sd2 at scsibus0 target 2 lun 0
sd3 at scsibus0 target 3 lun 0
sd4 at scsibus0 target 4 lun 0
sd5 at scsibus0 target 5 lun 0
sd6 at scsibus0 target 6 lun 0

sd10    at scsibus1 target 0 lun 0
sd11    at scsibus1 target 1 lun 0
sd12    at scsibus1 target 2 lun 0
sd13    at scsibus1 target 3 lun 0
sd14    at scsibus1 target 4 lun 0
sd15    at scsibus1 target 5 lun 0
sd16    at scsibus1 target 6 lun 0
sd18    at scsibus1 target 8 lun 0
sd19    at scsibus1 target 9 lun 0
sd20    at scsibus1 target 10 lun 0
sd21    at scsibus1 target 11 lun 0
sd22    at scsibus1 target 12 lun 0
sd23    at scsibus1 target 13 lun 0
sd24    at scsibus1 target 14 lun 0
sd25    at scsibus1 target 15 lun 0

cd* at scsibus? target ? lun ?  # scsi cds
ss* at scsibus? target ? lun ?  # scsi scanner
ch* at scsibus? target ? lun ?  # scsi autochangers
uk* at scsibus? target ? lun ?  # scsi unknown

[...]
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Q1: Is this the right way to do it?

Q2: is there no problem that sd8, sd9 and sd17 are not assigned?

[The devices sd10-sd25 were also built in /dev]

TIA

-- 
Cu  Georges Heinesch, Luxembourg
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