Inproper ada# assignment in 10-BETA2

[Patrick Powell]

On 09/27/14 15:15, Mehmet Erol Sanliturk wrote:
> On Sat, Sep 27, 2014 at 1:53 PM, Jin Guojun <jguojun at sbcglobal.net> wrote:
>
>> Installed 10-BETA2 on SATA port 4 (ad8) and then added another SATA port 3
>> (ad6), the system has not correctly enumerate the ada # for the boot device.
>> As original boot (without the second SATA drive), the ad8 is enumerated as
>> ada0 -- the boot drive:
>>
>> Sep 24 22:51:30 R10-B2 kernel: ada0 at ahcich2 bus 0 scbus2 target 0 lun 0
>> Sep 24 22:51:30 R10-B2 kernel: ada0: <Hitachi HDP725050GLA360 GM4OA50E>
>> ATA-8 SATA 2.x device
>> ...
>> Sep 24 22:51:30 R10-B2 kernel: ada0: Previously was known as ad8
>>
>>
>> However, after added another SATA drive (ad6), this new drive is assigned
>> to ada0, but ad8 has changed to ada1. This is incorrect dynamic device
>> assignment. FreeBSD has kept using fixed disk ID assignment due to the same
>> problem introduced in around 4-R (or may be slightly later), and after a
>> simple debate, a decision was made to use fixed drive ID to avoid such
>> hassle.
>>
>> If now we want to use dynamic enumeration for drive ID# assignment, this
>> has to be done correctly -- boot drive MUST assigned to 0 or whatever the #
>> as installation assigned to; otherwise, adding a new drive will cause
>> system not bootable, or make other existing drive not mountable due to
>> enumeration # changes.
>>
>> Has this been reported as a known problem for 10-R, or shall I open a bug
>> to track?
>>
>> -Jin
>>
>
>
>
> One point should be checked :
>
> On mainboards SATA ports are numbered from 0  or 1 to  upward .
> BIOS always uses first SATA drive for boot .  This is NOT related to the
> operating system .
> Therefore , it is necessary to check port numbers of existing drives and
> the bootable SATA drive should be connected
> to the smallest numbered SATA port among existent drives .
>
>
> For example , assume bootable drive is connected to SATA port 2 .
> New drive should be connected to a higher numbered SATA port .
> If there are only two SATA ports , then bootable drive should be connected
> to the first SATA port .
>
> If mainboard BIOS allows definition of any SATA port for boot , and
> bootable SATA port and drive is specified in there , again it may boot from
> that drive . Up to now , I did not see any BIOS which supplies such an
> ordering among SATA ports . Please check your BIOS for such a feature . If
> it is present you may use it , otherwise it is necessary to reconnect SATA
> cables .
>
>
> Thank you very much .
>
> Mehmet Erol Sanliturk
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>
Try the Dell Precision M6500 Laptop which has three SATA ports (two 
internal, one external) and you can via the BIOS select the boot 
drive.   It appears that for FreeBSD 9.3 the drives are all enumerated 
the same,  independent of which is the current boot drive.  Interesting...