On Thu, Oct 10, 2013 at 04:59:09PM +0100, Mark Wickens wrote:
Unfortunately, as nice a box as it is (that counts for most things
with a 68k in ;) FDDI to 10MB doesn't solve any problems for me as
the sole benefit is the jump to 100MB over the standard ethernet
card in the 3000/800, so any solution that is going to work would
need to give me access to 100MB+ at the other end of the FDDI.
A cheap little box running linux/*BSD/etc should be able to bridge
between FDDI and FastEthernet for you nicely.
Sure, it's not as sexy as some "real" gear, but will likely do the
trick.
It'll take far more than a 68K to do it, however. :)
-brian
On 10/10/2013 16:32, Paul_Koning at Dell.com wrote:
On Oct 10, 2013, at 10:59 AM, Mark Wickens <mark at wickensonline.co.uk> wrote:
... I have a DEC VNswitch 900XX plugged into a DEChub One MX - there are clearly modular parts to that, but I'm presuming there isn't a FDDI copper module that I would be able to use?
That looks different (same size, though). The one I was talking about is the DECbridge 900. I see some variations on the net -- DECbridge 900MX seems to be the same except that it has two AUI connectors instead of being all 10Base-T. And I think the original was a SAS (S port) while the MX is a DAS (A and B ports). http://decdoc.itsx.net/dec94mds/defbaina.pdf has details and a picture.
paul
Unfortunately, as nice a box as it is (that counts for most things with a 68k in ;) FDDI to 10MB doesn't solve any problems for me as the sole benefit is the jump to 100MB over the standard ethernet card in the 3000/800, so any solution that is going to work would need to give me access to 100MB+ at the other end of the FDDI.
Cheers, Mark.
--
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On Oct 10, 2013, at 10:59 AM, Mark Wickens <mark at wickensonline.co.uk> wrote:
... I have a DEC VNswitch 900XX plugged into a DEChub One MX - there are clearly modular parts to that, but I'm presuming there isn't a FDDI copper module that I would be able to use?
That looks different (same size, though). The one I was talking about is the DECbridge 900. I see some variations on the net -- DECbridge 900MX seems to be the same except that it has two AUI connectors instead of being all 10Base-T. And I think the original was a SAS (S port) while the MX is a DAS (A and B ports). http://decdoc.itsx.net/dec94mds/defbaina.pdf has details and a picture.
paul
On Oct 10, 2013, at 10:53 AM, Mark Wickens <mark at wickensonline.co.uk> wrote:
On 10/10/2013 15:29, Brian Hechinger wrote:
All this talk of FDDI makes me want to go get the 4000/500s. I have a
pair of QBus FDDI cards. I suppose I would have to make the Octane a
router between FDDI and ethernet. :)
-brian
On Thu, Oct 10, 2013 at 02:26:23PM +0000, Paul_Koning at Dell.com wrote:
If you have SAS NICs. you can connect a pair of them (S to S).
Thanks for all the info guys, I knew you'd be one hell of a knowledgeable lot!
If I understand what you are saying correctly, if I have NODE3 with the Turbochannel FDDI card (copper based) and a.n.other (call it NODE2 for arguments sake) ALPHA with a PCI FDDI Copper card I could wire them too together directly?
If that were so I would presumably need to do some routing within NODE2 to allow NODE3 access to network traffic if NODE2 was also connected to the 'great wide world' via ethernet.
Is there anything I'm missing in this picture?
You have the picture. You'll need a crossover (not straight through) cable. I went looking for data on the pinouts. It turns out the pins used by FDDI TP-PMD ("Twisted pair physical medium dependent layer") are distinct from 100Base-T, but a crossover cable that has all four pairs wired should serve. According to http://bitsavers.informatik.uni-stuttgart.de/pdf/national/_appNotes/AN-0965…, pins 1/2 are the transmit pair, 7/8 the receive pair.
So a SAS connection is like a point to point Ethernet connection: exactly two stations. Yes, that means that one (or both) endpoint needs to be either a bridge or a router for you to reach other nodes.
Earlier there was mention of the DEC full duplex mode. You can turn that on for this topology, if you want to. It may not be worth the trouble; the token ring overhead is pretty modest for short connections.
paul
On Thu, Oct 10, 2013 at 03:19:53PM +0000, Paul_Koning at Dell.com wrote:
I think this is the one I had. Big modular thing. Maybe (and going by
really fuzzy memory here) 8U high?
I was going to say "that sounds right" based on my memory of seeing one gathering dust around here. But the picture here: http://www.global-itcorp.com/products/digital-dec/networking/gigaswitch/ shows a much taller enclosure, half line card space and half power supply. Each section does look like 8U or so.
Hmmm. I wonder if those can be separated. I wonder if that also means
mine never would have worked. I don't remember having the bottom half.
That was also 10 years ago, so who knows, maybe I did have the whole
thing. :)
Some searching turns up refurbished Gigaswitch modules. Some are pretty cheap, but it looks like those are ATM ones, the FDDI ones I see quoted are more expensive. Perhaps because FDDI was fairly successful at least for a short time, while ATM (as a LAN) was an utter failure.
The *only* thing I even needed it to do was bridge FDDI/FastEthernet so
it just ended up not being worth the effort.
It's not a small switch. :)
-brian
On Oct 10, 2013, at 10:35 AM, Brian Hechinger <wonko at 4amlunch.net<mailto:wonko at 4amlunch.net>> wrote:
On Thu, Oct 10, 2013 at 02:32:26PM +0000, Paul_Koning at Dell.com<mailto:Paul_Koning at Dell.com> wrote:
...
Then there is the Gigaswitch, a large modular chassis with lots of line cards, some FDDI, some Ethernet, possibly some with other stuff I don't remember.
I think this is the one I had. Big modular thing. Maybe (and going by
really fuzzy memory here) 8U high?
I was going to say "that sounds right" based on my memory of seeing one gathering dust around here. But the picture here: http://www.global-itcorp.com/products/digital-dec/networking/gigaswitch/ shows a much taller enclosure, half line card space and half power supply. Each section does look like 8U or so.
Some searching turns up refurbished Gigaswitch modules. Some are pretty cheap, but it looks like those are ATM ones, the FDDI ones I see quoted are more expensive. Perhaps because FDDI was fairly successful at least for a short time, while ATM (as a LAN) was an utter failure.
paul
On Thu, Oct 10, 2013 at 05:00:14PM +0200, Johnny Billquist wrote:
If you could SAS as pure SCSI, SAS/SCSI converters are dirt cheap. ;)
Links? It's an obnoxious thing to search for. :)
Oops. I meant SAS/SATA. They're dirt cheap as you just grab the right
SFF cable. ;)
Might be. But both equally impossible to connect to your VAX, as it
actually have SCSI, and not SAS.
Yeah, completely not the same thing. :)
I did, but that shouldn't make any difference. It's just adapts between
different physical connectors. There is no magic in a 50-pin/SCA
adapter.
I must've had IDs and termination set wrong then.
Indeed. There are several different connectors for SCSI, but
adapters are available, and it's just straight wires between pins on
the different connectors.
The SCA adapters also add jumpers for ID selection and power as both
things come from the SCA backplane.
You can say that about anything you have to pay for. Or course it's
nicer if you could get it for free...
Free would be best, but reasonable cost would be fine, too. :)
-brian
On Thu, Oct 10, 2013 at 10:35:03AM -0400, Cory Smelosky wrote:
On Thu, 10 Oct 2013, Brian Hechinger wrote:
All this talk of FDDI makes me want to go get the 4000/500s. I have a
pair of QBus FDDI cards. I suppose I would have to make the Octane a
router between FDDI and ethernet. :)
I still need to get a QBus system. :(
They are neat.
Have one to spare? ;)
Sadly, no. :(
-brian
On 2013-10-10 16:31, Cory Smelosky wrote:
On Thu, 10 Oct 2013, Brian Hechinger wrote:
On Thu, Oct 10, 2013 at 10:21:37AM -0400, Cory Smelosky wrote:
If you could SAS as pure SCSI, SAS/SCSI converters are dirt cheap. ;)
Links? It's an obnoxious thing to search for. :)
Oops. I meant SAS/SATA. They're dirt cheap as you just grab the right
SFF cable. ;)
Might be. But both equally impossible to connect to your VAX, as it actually have SCSI, and not SAS.
This is patently untrue. The 146G disks in my 4000/90 prove that. :)
I'd be surprised if you weren't using an adapter to attach an SCA
drive. I tried that but the VAX didn't like seeing my 36G 10k RPM
drive. I also kept bumping it and shorting out the adapter on the
case...
I did, but that shouldn't make any difference. It's just adapts between
different physical connectors. There is no magic in a 50-pin/SCA
adapter.
I must've had IDs and termination set wrong then.
Indeed. There are several different connectors for SCSI, but adapters are available, and it's just straight wires between pins on the different connectors.
Iirc solid-state SCSI drives existed.
They did, and they still exist. They tend to be industrial grade stuff,
however and also tend to be silly expensive.
Yeah.
It's unfortunate, really. :(]
Yeah. :(
You can say that about anything you have to pay for. Or course it's nicer if you could get it for free...
Johnny
On 10/10/2013 15:32, Paul_Koning at Dell.com wrote:
On Oct 10, 2013, at 8:44 AM, Brian Hechinger <wonko at 4amlunch.net> wrote:
On Thu, Oct 10, 2013 at 02:36:04PM +0200, Peter Lothberg wrote:
...
For example cisco/cabletron/crecendo had ethnernet switches with a
FDDI uplink, that you could use.
DEC made one as well, it was that large modular thingie. I used to have
one. Never got it powered on as it was enormous.
DEC made at least three.
The original one is the DECbridge 500, a 3U rack mounted device, 3 or 4 cards, 3 Ethernets (10 Mb/s) to FDDI. See the DTJ issue I mentioned in my previous note.
The other two: the DECbridge 900, which plugged into the 900 series modular enclosure. It's about the side of a 400 page hardcover book, FDDI to 6 Ethernet ports, 60,000 packets per second using a MC68040 at 25 MHz. I'm still proud of that. (I wrote the "fast path" packet forwarding firmware.)
Then there is the Gigaswitch, a large modular chassis with lots of line cards, some FDDI, some Ethernet, possibly some with other stuff I don't remember.
paul
I meant to say that I have a DEC VNswitch 900XX plugged into a DEChub One MX - there are clearly modular parts to that, but I'm presuming there isn't a FDDI copper module that I would be able to use?
Thanks, Mark.
--
http://www.wickensonline.co.ukhttp://hecnet.euhttp://declegacy.org.ukhttp://retrochallenge.nethttps://twitter.com/#!/%40urbancamo
