Problem with multiple scsi adapters and drive assignments

Patrick C pcloches at
Tue Mar 18 16:09:13 PDT 2008

This is exactly what labeling your disks solves.

Please see info on 'tunefs' and 'glabel' which provide labels to
devices. Basically, when you insert a device not only does it get its
scan-order-based /dev/___, it also gets a named entry in either
/dev/ufs/ or /dev/label (tunefs/geom).

You then use the label to mount the drive.


On 18/03/2008, John A. <johna9999 at> wrote:
> I've searched all over (not totally exhaustive, but close) and can't find an
>  answer that I thought would have come up before.  Basically, I need to
>  change the order that the kernel assigns drive names on bootup.
>  It all started out with an old Intel server board with NCR/Symbios scsi
>  builton.  I added a QLogic QLA2100 fibre controller and everything was fine
>  except that it was a little slow and couldn't hold enough ram.  I took
>  another (newer) Intel server board and put it in the case.  This board has
>  an Adaptec AIC7896 builtin.  My custom kernel didn't have the aic driver so
>  I took the opportunity to upgrade to 7.0 and built a new kernel.  Everything
>  was fine until I turned on the external fibre chassis and found that my da0
>  became da7.  The board is in a rack-mount case so I cant put the QLA into a
>  different slot and the bios doesn't have any way to change irq settings on
>  the pci slots.
>  I my mind, the logical answer is to tell FBSD to scan ahc0 before isp0.
>  Through all my searching through docs and the mailing list archives, I can't
>  find any mention of how to do this.  I did find one mention of turning off
>  the bios on the offending scsi card (it was a system with 2 Adaptecs).  Been
>  there, tried that, didn't work.  Feel free to slap my face and call me
>  stupid as long as you point my to the proper info if I somehow missed it.
>  Here are the relevant parts of dmesg if that helps (I didn't include the
>  drives themselves since I can't get it boot with the external chassis turned
>  on):
>  FreeBSD 7.0-RELEASE #1: Mon Mar 17 14:43:04 EDT 2008
>     john at media:/usr/obj/usr/src/sys/MYKERN
>  Timecounter "i8254" frequency 1193182 Hz quality 0
>  CPU: Intel Pentium III (596.92-MHz 686-class CPU)
>   Origin = "GenuineIntel"  Id = 0x681  Stepping = 1
>  real memory  = 2139029504 (2039 MB)
>  avail memory = 2087882752 (1991 MB)
>  ACPI APIC Table: <Intel  N440BX  >
>  ioapic0 <Version 1.1> irqs 0-23 on motherboard
>  kbd1 at kbdmux0
>  acpi0: <PTLTD   RSDT> on motherboard
>  acpi0: [ITHREAD]
>  acpi0: Power Button (fixed)
>  Timecounter "ACPI-safe" frequency 3579545 Hz quality 850
>  acpi_timer0: <24-bit timer at 3.579545MHz> port 0xc08-0xc0b on acpi0
>  cpu0: <ACPI CPU> on acpi0
>  pcib0: <ACPI Host-PCI bridge> port 0xcf8-0xcff on acpi0
>  pci0: <ACPI PCI bus> on pcib0
>  agp0: <Intel 82443GX host to PCI bridge> on hostb0
>  pcib1: <PCI-PCI bridge> at device 1.0 on pci0
>  pci1: <PCI bus> on pcib1
>  pcib2: <PCI-PCI bridge> at device 15.0 on pci1
>  pci2: <PCI bus> on pcib2
>  isp0: <Qlogic ISP 2100 PCI FC-AL Adapter> port 0x2000-0x20ff mem
>  0xf4500000-0xf4500fff irq 19 at device 9.0 on pci0
>  firmware_get: failed to load firmware image isp_2100
>  isp0: [ITHREAD]
>  isp0: Board Type 2100, Chip Revision 0x3, resident F/W Revision 1.15.21
>  pci0: <simple comms> at device 11.0 (no driver attached)
>  ahc0: <Adaptec aic7896/97 Ultra2 SCSI adapter> port 0x2400-0x24ff mem
>  0xf4501000-0xf4501fff irq 19 at device 12.0 on pci0
>  ahc0: [ITHREAD]
>  aic7896/97: Ultra2 Wide Channel A, SCSI Id=7, 32/253 SCBs
>  ahc1: <Adaptec aic7896/97 Ultra2 SCSI adapter> port 0x2800-0x28ff mem
>  0xf4502000-0xf4502fff irq 19 at device 12.1 on pci0
>  ahc1: [ITHREAD]
>  aic7896/97: Ultra2 Wide Channel B, SCSI Id=15, 32/253 SCBs
>  Thanks in advance for your help, the archives of this list have been very
>  helpful over the past 5 years.
>  _______________________________________________
>  freebsd-questions at mailing list
>  To unsubscribe, send any mail to "freebsd-questions-unsubscribe at"

More information about the freebsd-questions mailing list