I believe dmraid is primarily a discovery tool. It interogates the system for fakeraid controllers and it can also look at metadata blocks on the drives themselves to look for fakeraid signatures. If it determines fakeraid is in use it does it's best to determine the appropriate configuration and tells the kernel how to properly interact with the drives. Here's the list of things dmraid claims to support:
$ /sbin/dmraid -l asr : Adaptec HostRAID ASR (0,1,10) ddf1 : SNIA DDF1 (0,1,4,5,linear) hpt37x : Highpoint HPT37X (S,0,1,10,01) hpt45x : Highpoint HPT45X (S,0,1,10) isw : Intel Software RAID (0,1,5,01) jmicron : JMicron ATARAID (S,0,1) lsi : LSI Logic MegaRAID (0,1,10) nvidia : NVidia RAID (S,0,1,10,5) pdc : Promise FastTrack (S,0,1,10) sil : Silicon Image(tm) Medley(tm) (0,1,10) via : VIA Software RAID (S,0,1,10) dos : DOS partitions on SW RAIDs --- ok... unfortunately, the only workstation I have right now that has one of these, Dell SAS 6/iR Integrated Workstation Controller is running Win7 where it gives about 3-4X throughput on a 4disk RAID0 (did I mention that all my data and programs are backed up on my server! ;-) and those 4 disks are solid state AND I have weekly image backups of the system disk?)
Last time I expanded -- (if you can do this on Windows, why not linux?) I used cygwin to run "dd" and make a full disk copy to an HD I put in a DVD slot temporarily. then added new solid state drives, configed them in the BIOS, then booted linux-recovery to 'dd' the image from the HD to the new Virtual drive & reboot!). I guess I don't see why a driver couldn't talk to a software RAID in the BIOS -- the lsi Megaraid (0,1,10) in your list seems to describe the SAS iR... Since all the reads/writes to those disks can be done in parallel with a SAS or SATA controller, it's like a nobrainer to create a low-resource raid 0/1/10...So I've not had much question about it being able to be done... but is a ROM emulating a low level HW piece still HW?? or a SW component? (the interior sas cables come directly off the motherboard). It's usually the base option for a new workstation with HW RAID being 300-700 more... It's BASED on this experience that I give the advice I give... a more limited raid.. that only works on linux didn't seem like a 'win'... -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org