2 eth cards in one box ...

2 eth cards in one box ...

Post by Charlie Wat » Thu, 01 Aug 1996 04:00:00



I'm going to be setting up a linux box to do masquerading for a bunch of
machines soon. I've already done it for a ppp connection, so I shouldn't
have any trouble, right? :)

Actually, what I want to know is which eth cards people have had luck with
installing 2 at a time ... or does most anything work? Or should I get two
different brands ?

One other (off topic) question: For a small network (~8 boxes), that isn't
going to get any bigger, and doesn't really have very large bandwidth
demands, should I go with 10baseT and buy a hub or can i just use 10base2
?

thanks
charlie
-- companion to our demons, they will dance and we will play --

 
 
 

2 eth cards in one box ...

Post by Geoff Sho » Fri, 02 Aug 1996 04:00:00


: Actually, what I want to know is which eth cards people have had luck with
: installing 2 at a time ... or does most anything work? Or should I get two
: different brands ?

Yep, not too many problems.  Look at the Multiple Ethernet mini-HOWTO
for guidance, and the Ethernet HOWTO for compatibility.  We also have
some stuff about two networks cards at
        http://kipper.york.ac.uk/netsetup.html

: One other (off topic) question: For a small network (~8 boxes), that isn't
: going to get any bigger, and doesn't really have very large bandwidth
: demands, should I go with 10baseT and buy a hub or can i just use 10base2?

If you don't need huge bandwidth then 10base2 should be fine, and more
to the point, cheap.

        Geoff
--
----------------------------------------------------------------------------


can't identify with that kind of work ethic. http://kipper.york.ac.uk/~geoff

 
 
 

2 eth cards in one box ...

Post by WEILL Philipp » Fri, 02 Aug 1996 04:00:00



> I'm going to be setting up a linux box to do masquerading for a bunch of
> machines soon. I've already done it for a ppp connection, so I shouldn't
> have any trouble, right? :)

> Actually, what I want to know is which eth cards people have had luck with
> installing 2 at a time ... or does most anything work? Or should I get two
> different brands ?

I'm using linux with 2 Network card
one is a 3c59x ,the others is a 3C509Combo
all network driver are compiled as modules and loaded by kerneld
(kernel 2.0.x RedHat 3.0.3 base )
works fine
Quote:> One other (off topic) question: For a small network (~8 boxes), that isn't
> going to get any bigger, and doesn't really have very large bandwidth
> demands, should I go with 10baseT and buy a hub or can i just use 10base2
> ?

On my network (about one hundred box connected)I'm using the 2 cabling system
10base2 works fine with small networks but if you have a problem on one card or
with cable, all the network is down.This appens about once a month
With 10baseT we don't have this problem and it's works fine

Now 10baseT hub are really cheap so i think it's better and you can after upgrade
to use 100baseTX without changing your cabling system just Hub and NIC

Quote:

> thanks
> charlie
> -- companion to our demons, they will dance and we will play --

Hope this help
--
|--------------------------------------------------------------------------|
| Weill Philippe                       |  CNRS Service Aeronomie           |
| System and Network Manager           |  Universite Pierre et Marie Curie |
| Tel: +33-1-44274759                  |  Tour 15 Couloir 15-14            |
| Fax: +33-1-44273776                  |  4 Place Jussieu                  |
|                                      |  75252 Paris Cedex 05             |

|--------------------------------------------------------------------------|
 
 
 

2 eth cards in one box ...

Post by edham.. » Fri, 02 Aug 1996 04:00:00


Quote:>  One other (off topic) question: For a small network (~8 boxes), that isn't
>  going to get any bigger, and doesn't really have very large bandwidth
>  demands, should I go with 10baseT and buy a hub or can i just use 10base2
>  ?

This largely depends on your individual preferences, the proximity of the workstations,
and your budget. 10base-t adaptors are a little less expensive, but the cost of an 8 port
(or more) hub will eat up that savings quickly. If your workstations are located in close
proximity, coax (10base-2) will work just as well.

In my ethernet installations, I will typically cable most of the equipment in the server
room (servers, admin workstations, etc) using coax, and connect one end of that coax
cable to my 10base-T hubs. This allows me to easily patch additional server room
equipment  into the cable without using hub ports (which are usually at a premuim).
When you use coax, always put a couple of additional T-connectors in the line for just
this purpose.

Ed Kleinhample
Consultant - Land O' Lakes, FL.

 
 
 

2 eth cards in one box ...

Post by lemah.. » Fri, 02 Aug 1996 04:00:00



> One other (off topic) question: For a small network (~8 boxes), that isn't
> going to get any bigger, and doesn't really have very large bandwidth
> demands, should I go with 10baseT and buy a hub or can i just use 10base2
> ?

I've seen some replies to this as well, and I don't understand the bandwidth
concern.  They're both 10Mbps, plain and simple.  "..just use 10Base2" sounds
a little odd to me, since it's not a performance issue, but rather a layout
and maintenance issue.

The hub just gives you a bus where you don't have to worry about laying things
out in a straight line or bringing down the net whenever you add/remove some
machine.  If the machines are in different offices, 10BaseT is most convenient.
If you've got all the machines in the same lab, either is fine, and 10Base2 is
often more convenient.  I mean, if you've got two rows of computers, laying out
8 5-meter wires is awkward when compared with just stringing one wire from
machine to machine.  However, if you've got a set of offices, placing a hub
in a central location a running a wire to each machine is easiest and more
versatile.

--Paul

 
 
 

2 eth cards in one box ...

Post by Gary Hest » Sat, 03 Aug 1996 04:00:00




>> One other (off topic) question: For a small network (~8 boxes), that isn't
>> going to get any bigger, and doesn't really have very large bandwidth
>> demands, should I go with 10baseT and buy a hub or can i just use 10base2
>> ?
>I've seen some replies to this as well, and I don't understand the bandwidth
>concern.  They're both 10Mbps, plain and simple.  "..just use 10Base2" sounds
>a little odd to me, since it's not a performance issue, but rather a layout
>and maintenance issue.

Not quite. 10BaseT incurs a repeater delay each time you go in or out
of a 10BaseT hub--so, if you connect a host to a workstation through a
hub, you have two repeater delays in the path (one going in, one coming
out). Cascading hubs makes it worse. 10Base2 doesn't incur any repeater
delays at all, so you end up with more usable bandwidth using coax
instead of twisted pair. The Ethernet spec limits you to five repeater
delays, beyond which performance will start to degrade.

Quote:>The hub just gives you a bus where you don't have to worry about laying things
>out in a straight line or bringing down the net whenever you add/remove some
>machine.  If the machines are in different offices, 10BaseT is most convenient.
>If you've got all the machines in the same lab, either is fine, and 10Base2 is
>often more convenient.  I mean, if you've got two rows of computers, laying out
>8 5-meter wires is awkward when compared with just stringing one wire from
>machine to machine.  However, if you've got a set of offices, placing a hub
>in a central location a running a wire to each machine is easiest and more
>versatile.

It also depends on how much area you're needing to cover, and how far apart
you need connections. 10BaseT is limited to 100m, whereas 10Base2 can go
185m (actually, it'll go further, but that's the spec; I recall someone
finding a 1200m 10Base2 net that was slow, but functioning). The office
area I'm in right now I had to wire with 10Base2 (managment politics). I'm
in the process of converting to 10Base2, but my labs and manufacturing lines
are almost all 10Base2 due to distances and the need to get every bit of
bandwidth out of the cables I can. We build computers, and install software
via a networked arrangement. The image files tend to run around 130-160MB
each, and with 16 servers feeding about 120 "hubs" (computers with special
16 port parallel cards, no relation to 10BaseT) trying to download to
4000-4300 computers per shift, I don't have bandwidth to waste.

Each situation is different....

Gary

--

   The Chairman of the Board and the CFO speak for SCI. I'm neither.
"All the observing stops, of course, when the observer hits the
singularity at the center of the black hole." Dr. Robert L. Forward

 
 
 

2 eth cards in one box ...

Post by Daniel Perry Pinka » Sun, 04 Aug 1996 04:00:00


: I'm going to be setting up a linux box to do masquerading for a bunch of
: machines soon. I've already done it for a ppp connection, so I shouldn't
: have any trouble, right? :)

No reason it should be - Linux doesn't care WHAT the device is as long as
it exists...

: Actually, what I want to know is which eth cards people have had luck with
: installing 2 at a time ... or does most anything work? Or should I get two
: different brands ?

I generally use 3c509's just becuase I've never had a problem with them.
I'm running them as a birdge and haven;t really tried to pount on them
but they seem to work fine. I plan on adding another card or two to it
after the code is out of alpha.. we'll see how that goes.

: One other (off topic) question: For a small network (~8 boxes), that isn't
: going to get any bigger, and doesn't really have very large bandwidth
: demands, should I go with 10baseT and buy a hub or can i just use 10base2
: ?

Not really. 10baseT is good if there's a chance that any peice of the
network might be disconnected and can ease wiring, but other than that...

d.p.

--

+-----------------------------------------------------------------+
| Dan Pinkard                  Washington University in St. Louis |

| www.cec.wustl.edu/~dpp1/     NextLevel Grunt  www.nextlvl.com   |
|        "I know the truth because I know the source code."       |
+-----------------------------------------------------------------+

 
 
 

2 eth cards in one box ...

Post by Jeff Wellemey » Sun, 04 Aug 1996 04:00:00


I have had the best luck using the lest expensive, no name brand, NE2000
compatible cards that have jumper settings.  I think it is easier with
the autodetect to use two of the exact same cards, but it works fine
using different ones.



Quote:

>I'm going to be setting up a linux box to do masquerading for a bunch
of
>machines soon. I've already done it for a ppp connection, so I
shouldn't
>have any trouble, right? :)

>Actually, what I want to know is which eth cards people have had luck
with
>installing 2 at a time ... or does most anything work? Or should I get
two
>different brands ?

>One other (off topic) question: For a small network (~8 boxes), that
isn't
>going to get any bigger, and doesn't really have very large bandwidth
>demands, should I go with 10baseT and buy a hub or can i just use
10base2
>?

>thanks
>charlie
>-- companion to our demons, they will dance and we will play --

 
 
 

2 eth cards in one box ...

Post by Robert Komane » Tue, 06 Aug 1996 04:00:00


<snip snip upto DELAYS>

Quote:> Not quite. 10BaseT incurs a repeater delay each time you go in or out
> of a 10BaseT hub--so, if you connect a host to a workstation through a
> hub, you have two repeater delays in the path (one going in, one coming
> out). Cascading hubs makes it worse. 10Base2 doesn't incur any repeater
> delays at all, so you end up with more usable bandwidth using coax
> instead of twisted pair. The Ethernet spec limits you to five repeater
> delays, beyond which performance will start to degrade.

<snip snip upto DISTANCE and BANDWIDTH>

Quote:> It also depends on how much area you're needing to cover, and how far apart
> you need connections. 10BaseT is limited to 100m, whereas 10Base2 can go
> 185m (actually, it'll go further, but that's the spec; I recall someone
> finding a 1200m 10Base2 net that was slow, but functioning). The office
> area I'm in right now I had to wire with 10Base2 (managment politics). I'm
> in the process of converting to 10Base2, but my labs and manufacturing lines
> are almost all 10Base2 due to distances and the need to get every bit of
> bandwidth out of the cables I can. We build computers, and install software
> via a networked arrangement. The image files tend to run around 130-160MB
> each, and with 16 servers feeding about 120 "hubs" (computers with special
> 16 port parallel cards, no relation to 10BaseT) trying to download to
> 4000-4300 computers per shift, I don't have bandwidth to waste.

Your pro's are valid just in case of a no_further_development network.
In case you ever want to do something with the net, the TP is much
more convenient. Just think of (a) adding a switch [your bandwidth problems
are gone], (b) moving half of your computers somewhere else, (c) adding
[many] more machines, ...
We do have a coax network here, which started (as usualy) with a few machines,
and now goes over 4 floors and I_don't_want_to_know how many meters. The only
think we wish (and work on) is a nicely layed out structure with a switch...

Quote:> Each situation is different....

Correct.

Robert Komanec running linux

 
 
 

2 eth cards in one box ...

Post by Charlie Watt » Tue, 06 Aug 1996 04:00:00


I just wanted to thank everyone for helping me ... I think I've decided to
go with 10bt, just because one day we may expand a little ... upstairs
offices, I mean. Interesting about the speed ... I didn't realize that
hubs added a delay. Somehow I was assuming that 10bt is faster, just
'cause everyone sort of implies it. Explains why there is a limit to the
number of hubs between any number of devices.

Thanks again, everybody.

charlie
-- companion to our demons, they will dance and we will play --