>
>
> >There *IS* one limitation in the Linux SCSI subsystem that may be biting
> >you -- it only addresses up to 16 devices. That's all, folks! Obviously
> >this is something that has to be changed before Linux can be taken
> >seriously in the high-end storage department.
See earlier post on setting "max_id" in host structure.
An alternate methodology is to set max_channels up to be "virtual"
scsi busses and use 16 per virtual channel.
> There are lots of caveats to the above mentioned 16 device limit. RH6.1
> (kernel 2.2.12-20) will do more than 16 devices/LUNs IF you run the
> /dev/MAKEDEV script to create more devices ("out of box" stops at
> /dev/sdpX).
>
> The real killer is the limit of 4 devices on a secondary SCSI bus due to
> SD_EXTRA_DEVS. I'm testing a 11.2TB subsystem for Linux compatibility.
> You ever tried to hide 11.2TB behind a grand total of FOUR LUNS?!? ;)
> I've heard future releases will take this to 40, but you can fit
> 127 devices on a FC-AL. sigh.
I have seen no problems tuning SD_EXTRA_DEVS up to 40 and beyond.
If necessary I'll test with 80+ drives to verify.
--
Mark Veteikis [EMAIL PROTECTED] 1-214-654-5257
Interphase Corp. 13800 Senlac Dallas Tx. 75234
-
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to [EMAIL PROTECTED]
