On Thu, 10 Oct 2013, Mark Wickens wrote:
Even though I think I know the answer to this question, I'll ask it any way...
Is it OK to run machines that are in the same area on different subnets? For example, passing traffic between SLAVE:: and RIPLEY:: both on DECnet area 4 but on different subnets connected via a bridge?
Should be fine so long as it can still find the MAC addresses.
I think it is and that the bridge is transparent, but for some reason in the back of my mind I have the concept of 'area router' and that doesn't fit with this model.
Thanks, Mark.
--
Cory Smelosky
http://gewt.net Personal stuff
http://gimme-sympathy.org Projects
On Oct 10, 2013, at 4:19 AM, Mark Wickens <mark at wickensonline.co.uk> wrote:
Even though I think I know the answer to this question, I'll ask it any way...
Is it OK to run machines that are in the same area on different subnets? For example, passing traffic between SLAVE:: and RIPLEY:: both on DECnet area 4 but on different subnets connected via a bridge?
I think it is and that the bridge is transparent, but for some reason in the back of my mind I have the concept of 'area router' and that doesn't fit with this model.
"Subnet" is an IP term, it has no relevance to DECnet nor to Ethernet. Since you mentioned bridges, the term to use is "LAN". (A bridge connects LANs into an Extended LAN).
And yes, as others have answered, bridges are transparent to routers.
The area router rule is that area routers have to be directly connected. "Directly" means a datalink layer path between L2 routers, either a point to point link (DDCMP for example) or a LAN link. More precisely, for the latter case that is "Extended LAN link".
paul
On Thu, 10 Oct 2013, Daniel Soderstrom wrote:
Has anyone tries this? Running my Vaxstation non-stop reminds me how much noise these old drives make.
I have my VAXstation sitting atop a cisco 3745. I don't even hear the drives! ;)
Has anyone tried SSD drives? Must be good for the PSU it terms of heat and current draw.
Daniel
Sent from my iPhone
--
Cory Smelosky
http://gewt.net Personal stuff
http://gimme-sympathy.org Projects
FDDI/CDDI is a dual ring token ring bus, with 4470 MTU byte packets,
it has 802.-- frames. DEC had a mode where you turned the token off
and used it for ptp full duplex.
I didn't know about the ptp thing. That's nifty.
A cisco FDDI-PA can talk both in a 7500 or old 7200 (the VXR don't
support the FDDI cards but the VIP does ).
I don't think there ever was a CDDI PA..
Sol.Stupi.SE that has a CDDI interface has a media converter from
copper to fiber and then it plus in to a old 7200...
-P
On Thu, Oct 10, 2013 at 02:36:04PM +0200, Peter Lothberg wrote:
FDDI/CDDI is a dual ring token ring bus, with 4470 MTU byte packets,
it has 802.-- frames. DEC had a mode where you turned the token off
and used it for ptp full duplex.
I didn't know about the ptp thing. That's nifty.
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.
But you need nothing to build a FDDI ring, its a A and a B ring, you
can just plug the cards together with fiber-patch-cables.
Unless you have one of those obnoxious single attached station cards.
-brian
I guess this is sort of on-topic, given I am talking about networking.
The Alpha 3000/800 I have contains a PMAF-FU card which is a DEC
FDDIcontroller TURBOchannel card. It has a CAT 5 copper FDDI interface.
I understand that it will support networking at 100MB.
It was called CDDI (copper.... instead if fiber...)
I have no knowledge of FDDI. I believe that I would need a concentrator
to make use of this connection, is there such a device which I could use
to bridge the 3000/800 using FDDI to a standard ethernet network?
FDDI/CDDI is a dual ring token ring bus, with 4470 MTU byte packets,
it has 802.-- frames. DEC had a mode where you turned the token off
and used it for ptp full duplex.
There where converters that made Copper-to-Fiber conversion at L1 and
then you could plug in a normal FDDI hub/switch.
For example cisco/cabletron/crecendo had ethnernet switches with a
FDDI uplink, that you could use.
As a second question, I have a number of DEC/Compaq/HP PCI FDDI cards
which were given to me. They have optical connectors. If I were to make
use of these would I need another concentrator, or is there a box which
will support both media with plug in modules, for example.
Cabletron made such thing...
But you need nothing to build a FDDI ring, its a A and a B ring, you
can just plug the cards together with fiber-patch-cables.
-P
Thanks for the help,
Mark.
--
http://www.wickensonline.co.ukhttp://hecnet.euhttp://declegacy.org.ukhttp://retrochallenge.nethttps://twitter.com/#!/%40urbancamo
I guess this is sort of on-topic, given I am talking about networking.
The Alpha 3000/800 I have contains a PMAF-FU card which is a DEC FDDIcontroller TURBOchannel card. It has a CAT 5 copper FDDI interface. I understand that it will support networking at 100MB.
I have no knowledge of FDDI. I believe that I would need a concentrator to make use of this connection, is there such a device which I could use to bridge the 3000/800 using FDDI to a standard ethernet network?
As a second question, I have a number of DEC/Compaq/HP PCI FDDI cards which were given to me. They have optical connectors. If I were to make use of these would I need another concentrator, or is there a box which will support both media with plug in modules, for example.
Thanks for the help,
Mark.
--
http://www.wickensonline.co.ukhttp://hecnet.euhttp://declegacy.org.ukhttp://retrochallenge.nethttps://twitter.com/#!/%40urbancamo
On 2013-10-10 10:19, Mark Wickens wrote:
Even though I think I know the answer to this question, I'll ask it any
way...
Is it OK to run machines that are in the same area on different subnets?
For example, passing traffic between SLAVE:: and RIPLEY:: both on DECnet
area 4 but on different subnets connected via a bridge?
I think it is and that the bridge is transparent, but for some reason in
the back of my mind I have the concept of 'area router' and that doesn't
fit with this model.
The bridge is totally transparent, and makes it look like both sides are on the same ethernet segment.
An area router in between is also perfectly fine. Nodes in the same area can be spread out over any distance. The only requirements is that you got to have level 1 routers on all the hops in between. And area router is a level 2 router, but I have yet to see a level 2 router which do not also do level 1 routing.
Johnny
--
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: bqt at softjar.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
On 2013-10-10 09:46, Mark Wickens wrote:
On 10/10/2013 08:17, Daniel Soderstrom wrote:
Has anyone tries this? Running my Vaxstation non-stop reminds me how
much noise these old drives make.
Has anyone tried SSD drives? Must be good for the PSU it terms of heat
and current draw.
Daniel
Sent from my iPhone
There has been very little success with IDE to SCSI converters on this
age of machine.
Hmm. bad IDE to SCSI converters?
Remember also that even 4000/90 vintage VAXstations generally have an
upper limit of 18GB.
Uh? That got to be a limit in VMS in that case. I can't see how the hardware would have that limit.
I don't recall anyone even getting an IDE drive to work, let alone an SSD.
IDE and SSD are two completely unrelated things as such. However, if the SSD have an IDE interface, then you obviously need the IDE to SCSI converter.
Would love to be proved wrong however! I'm surprised someone hasn't
written a software based SCSI drive emulator the same way that you get
floppy emulators.
Probably mostly because of speed issues. You have some very tight timing requirements, and a SCSI interface runs way faster than a floppy.
Consider running the machine diskless, booted off the network with
off-node disks.
That definitely also works.
Johnny
--
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: bqt at softjar.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
As long as it is a layer two bridge with no layer 3 (router) capabilities for decnet then the should be no issue.
Area routers exist to connect machines in different decnet areas (level 2 inter area) but you also have Level 1 intra area routers for connecting nodes in the same area together across wide area links or multiple local area networks.
Bridging would be easiest and would allow LAT traffic to pass as well.
Mark
On 10 Oct 2013, at 09:19, Mark Wickens <mark at wickensonline.co.uk> wrote:
Even though I think I know the answer to this question, I'll ask it any way...
Is it OK to run machines that are in the same area on different subnets? For example, passing traffic between SLAVE:: and RIPLEY:: both on DECnet area 4 but on different subnets connected via a bridge?
I think it is and that the bridge is transparent, but for some reason in the back of my mind I have the concept of 'area router' and that doesn't fit with this model.
Thanks, Mark.
--
http://www.wickensonline.co.ukhttp://hecnet.euhttp://declegacy.org.ukhttp://retrochallenge.nethttps://twitter.com/#!/%40urbancamo
