[Info-vax] Alphaserver DS10s for sale

[chris]

On 1/18/23 04:24, Rich Jordan wrote:
> Was there a SAS controller that would work with Alpha VMS on DS10/15/20/25 machines with the restrictions that it couldn't boot from that controller?
> 
> Or were they just faster unsupported parallel SCSI controllers (U320) or RAID controllers that worked for data disks on those systems?
> 
> Right now my franken-DS10 has a KZPEA with multiple IBM 2.5" U320 73GB disks drives (largest capacity 2.5" parallel SCSI drives I've found) in hot-swap server 4-drive shelves installed into former full height DAT drive housings, which is more than adequate for my needs; I don't want noisy universals.  And so far it has been fast enough for my needs except for very occasional huge compiles.
> 
> These new systems are faster than mine (466 -> 617MHz).  Faster I/O would definitely help but again this is only for rare occasions.
> 
> I've got a pile of things to try eBaying or Craigslisting that would help offset the cost...

I looked for a dec supported scsi controller back in the days when I
ran a 500/400, Tru64, but not thick on the ground here in the uk
and very expensive. Before Ebay, so no bargains from the US either.

Perhaps the most common sas controllers are the LSI Logic types,
sas1068 and others, which all the mainstream vendors seem to
rebadge. They do have an onboard rom bios to set up various raid
configurations, diags etc, but of course, that is X86 / pc code
which won't work on non X86 unless the vendor modifies the code
to suit the architecture. If not, there must be either standalone
or os based utilities to do that.

The HP smart array range are pretty well sorted. The usual rom
bios entered at boot to config, and in a raid setup, if a drive
goes down, just replace the drive and it will rebuild in the
background with no power down or reboot required. Pretty
bulletproof all round.

Chris

> 
> 
> On Tuesday, January 17, 2023 at 7:57:51 PM UTC-6, gah4 wrote:
>> On Tuesday, January 17, 2023 at 6:55:22 AM UTC-8, chris wrote:
>>
>> (snip, I wrote)
>>>> They are SAS SCSI disks, which are slightly rare amount SCSI disks,
>>>> but not all that hard to find. And mine came with sleds, so I didn't
>>>> have to worry about those.
>>
>>>> Some ship without, and sleds are sometimes hard to find.
>>
>>> I've more or less standardised on 2.5" sas now. Sata are usually
>>> limited to 7200 rpm, whereas sas are 10 or 15K, even 2.5". Much
>>> faster access times and lower rotational latency.
>> I got four of the ST914602S, 146GB drives, including the
>> right sleds for the T5220, for $18.
>>> A lot of the 2.5 sas drives around now, as users discard rotating
>>> drives for ssd types. One Ebay seller here in the uk had hundreds
>>> of them, all in boxes, netapp mainly and won 2 lots of 2.5 sas
>>> 1200Mb (1.2Tb), 10 in the lot, for around 100 ukp. Some 450 and 600's
>>> prior to that as well. They have an mtbf of well over 10e6 hours
>>> and not a single duff one here yet...
>> As I understand it, you can always connect SATA disks to a SAS
>> controller, but not the other way around.
>>
>> But also, many current motherboards might have a SAS controller,
>> marketed as SATA. I have seen Unix-like systems use the SCSI
>> driver for what I thought were SATA.
>>
>> But I now have a Synology box running with four 500GB SSD
>> as RAID 5, and with gigabit Ethernet running NFS.
>>
>> But I might try a SATA SSD in the T5220, just to see it work.