Rodger Wilson writes:
> It seems to me that there are two types of persistence:
>
> a) real time reconfiguration (via lips, etc)
>
> Right now I only fibre channel has this problem. That is the problem of
> device changing their target (APLA) change while still running. These,
> devices should be refered to by their WWN while in the frame work, and
> then having the HBA change the WWN into an ALPA just before send the
> CDB. This can be done with a simple lookup table within a HBA.
Jargon alert! I have no idea what you're saying.
> b) rebooting persistence.
>
> Here we want a computer to talk to the same device after having been
> rebooted. For devices like IDE & SCSI the issue is fairly easy, we
> simply want a path to represent name like disk0. But in FC we need
> a name to be associated with a framework path and a paticular disk
> drive. This can be handled with in the /etc/devfsd.conf
Jargon again. "Framework path"?
> /etc/devfsd.conf
>
>
> /dev/discs/disc0 /dev/ide/hd/c0b0t0u0
> /dev/discs/disc1 /dev/scsi/host1/bus2/t3,4
> /dev/discs/disc2 /dev/fc/host1/bus3/wwn2100002037265f98,0
>
> Then when the system loads it creates these links & nodes even if
> the drive is missing, then if io goes down to the HBA for a target
> the HBA can look up the WWN and send io to the target if it is found
> else return error. This would allow for persistence even if the
> drive was not available untill 5 mins after reboot.
How about sending this whole message again in a form I can digest?
Regards,
Richard....
Permanent: rgooch@atnf.csiro.au
Current: rgooch@ras.ucalgary.ca
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