The market segment of RAID adapters has a long history and tradition,
and has undergone gradual concentration, followed by upstream
mergers of the owning corporations - a feeding frenzy of sorts,
among the semiconductor manufacturers.
I've been carrying the idea in my head for a while,
that an "oriented graph" depicting the gradual takeovers
would be interesting. Recently while fumbling in the interwebs
for some details of those events, I realized that my memory
of companies from 20 years ago is quickly fading away,
and it has occurred to me that it was about time
I sketched the chart.
Both Adaptec and LSI sell their RAID adapters under their own brand via retail stores, but also in volume to large OEMs such as HP, Dell, IBM/Lenovo and Fujitsu. Intel-branded RAID cards can be LSI or historically ICP-Vortex, under the hood.
Evidently, throughout the history there have been several firmware strains / code bases. And for practical purposes, the firmware strain is the key "selection criterion" that you are probably interested in, when shopping for a RAID card (or when trying to make one work.) In the chart above, currently the remaining strains appear to be the MegaRAID and AAC RAID - each getting new models introduced as the technical evolution goes on.
The clearest way for you to know, of what pedigree the RAID card
at hand is, is probably to insert it in a PC running a modern Linux
distro (or a recent FreeBSD release) and see what driver gets loaded.
For hardware currently in stores, you may need a fresh kernel,
possibly vanilla compiled from source (with all the RAID drivers
as modules).
Alternatively, try downloading a Windows driver for the card,
= for the marketing name that you can see in the e-shop.
Unpack the download by 7-zip until you get your hands on a pair of files
with .sys and .inf extensions. The INF is a text script,
tends to be kind of human readable, and if you haven't found
out by the filename yet, the INF "header comments" will probably
disclose the true pedigree of the card.
Wikipedia appears to be a rich source of memorial pages
for companies that no longer exist,
but even Wikipedia doesn't have them all.
And, companies that are still alive tend to have
a proper website of their own ;-)
Mylex
AMCC/3ware
LSI Logic
Avago, now Broadcom (ex Agilent, ex HP)
Adaptec
DPT
PMC-Sierra
Microsemi
Microchip
Areca
Infortrend
Accusys
Fujitsu Eternus DX (family overview PDF)
(Dell) EMC
After each of the early acquisitions, the surviving brand used to sell RAID controller models with different firmware strains - for a while. And what's nice, typically the strain with a more practical user interface and set of features has survived in the long term.
Such as, I recall cheap ZCR modules by Adaptec, the 2010/2015, being of the DPT/I2O pedigree, and later modules, the 2020/2025, being of AAC pedigree. By that time, the DPT ZCR cards felt a little stale, the AAC ZCR cards had a more useful firmware - but it turned out, that both strains probably suffered from a systemic hardware problem in the motherboards of those times, where the onboard AIC7902 (Adaptec U320 SCSI HBA chips) would have an insidious glitch against the ServerWorks chipsets on those same motherboards, in the PCI bus. No matter what ZCR was installed, all of them would freeze under stress. The solutions were: either pick a motherboard with an Intel server chipset (stay clear of ServerWorks) or buy a full-fledged RAID card, based on an Intel IOP SoC, that had its own HBA chips private to the SoC, so that they wouldn't come in contact with the ServerWorks chipset on the motherboard...
LSI inherited (purchased) their SCSI HBA silicon know-how
/ IP from NCR/Symbios. In the LSI camp, U160 and U320 SCSI
typically worked just fine, as long as your cabling was
allright. Many other RAID controller brands of the SCSI era
(Infortrend, Areca, Accusys) were using target-mode HBA
chips by LSI.
I also recall the time when the Mylex DAC960-descended
AcceleRAID and MegaRAID were both available under
the LSI brand, for a brief period of time - and the
MegaRAID was significantly more comfortable to use
and more powerful. You had to know what you're looking
at in the store. And later, for a while the 3ware models
were also suddenly available under the LSI brand...
The ICP Vortex GDT RAID adapters used to have a fairly nice BIOS menu and straightforward firmware. After the acquisition by Adaptec, I recall some Vortex cards being sold under the Adaptec brands... but looking at the listing of models of the AAC family, I can also see some ICP Vortex branded cards, maybe even pretty modern, which seems weird... Adaptec / Broadcom trying to capitalize on the ICP Vortex brand on the German market maybe?
A good overview of the history is available in the C source code
of the Linux drivers for the various RAID controller firmware strains.
Just try and find the table of PCI ID's supported,
typically commented and showing the controller's marketing names
and sometimes internal codenames. A good keyword to search for
is "struct pci_device_id" .
MegaRAID SCSI PCI
| MegaRAID SAS
AAC RAID
DPT RAID
ICP Vortex GDT
Mylex old
| new
Maybe a few words on the silicon side of things. On the chips that all the RAID controllers are based on.
The early Adaptec AAC RAID models had LSI HBA chips,
a PowerPC CPU and an Intel (nee DEC) PCI bridge.
This was the era of the Compaq SmartArray 4200
and probably still the Adaptec ASR-5400S.
Later Adaptec RAID cards had Adaptec-own HBA chips
(the AIC7899 U160) and an Intel IOP CPU,
originally with an i960 RISC core,
later with an ARM core.
The other RAID controller vendors were using
a similar component base.
For some years, Intel was dominating the market
for RAID controller CPU's, with its IOP processors.
To the extent that the CPU was becoming a bottleneck.
(Only some high end enterprise RAID controllers were
based on x86 processors.)
At about the time that SAS arrived, things were starting
to change. AMCC brought their SoC with a dual PowerPC CPU,
and other foundries followed with a plethora of SoC/RoC
chips, typically with a multi-channel SAS HBA integrated.
LSI, Marvell, Avago, Vitesse, Broadcom seem to ring a bell...
there were probably some mergers too, and ASIC IP core
transfers and startups etc. Nowadays it may be difficult
to find out the silicon pedigree of a RoC in someone's
RAID adapter. And, noone's very interested really,
because things "just work" and low-end RAID adapters
are no longer the rage of the day.
Heh: on-premises IT is no longer the rage of the day. The Cloud has made anything on-premises feel so guilty and backward, right? :-) And the massive cloud infrastructures themselves have hardly any use for dedicated RAID adapters. The storage back end consists of plain HBA's interfacing bulky slow spinning drives, or NVMe-attached Flash, JBOD style - and everything on top is software defined, running on cheap multicore CPU's with an ocean of RAM, communicating over Ethernet and TCP/IP, HTTP, JSON...
Dedicated RAID controllers are struggling to survive in niches such as industrial process control PC's, video editing workplaces, or miscellaneous die-hard on-premises enterprise-level systems, operated by grey-beard admins turned gradually into punks by the cloudy world speeding by...
By: Frank Rysanek [ rysanek AT fccps DOT cz] in September 2020