Mac Network question - Appletalk and Dual Ethernet Apple Desktops

[benbartlett]

The latest desktop Macs have 2 independent Ethernet ports with unique addresses. Can I use the second one to create a VE3 network WITHOUT enabling Appletalk on this port? Obviously I would need to invest in a second Gigabit switch for all this. Is VE3 a kind of peer to peer system? If yes, this would liberate my otherwise busy main network - which hosts video streams et al. Thanks to anyone who knows this.

[MS]

Yes you can.

In fact, this is an absolutely ideal setup for a VE3 power user, to have a separate network connection just for VE3 traffic. VE3 does not use Appletalk, so this can of course be switched off.

In my tests, I've seen that most gigabit implementations in laptops and pc's are capable of around 30-35MB/sec, so if you would need more than around 120 stereo tracks over network, you could always add another network card to your master and slave machines and distribute the load over the two interfaces.


Martin

[benbartlett]

That's brilliant that VE does not require Appletalk. It makes sense of course, given that its cross platform. And very good thinking about adding a network card- I was wondering what track bandwidth to expect from a Gb network. And of course there'll be no shortage of PCI slots as we don't need a soundcard!! Wondering what to do with my 7 (yes 7) 2408's now.... Thanks.

[cm]

there is an important point to be added: those (multiple) network adapters need to have the capability of *teaming* which a) needs 2 NICs (= Network Interface Cards) of the same model and b) the respective driver has to support it. you should leave such a configuration to a network expert ....

 

also be aware of the following: having 2 NICs in a computer makes it basically neccessary that both reside in their own network segment and only one of them has a gateway set (in OS X also called router)

 

what is a network segment:

we are focussing on the classical IPv4 TCP/IP network type where an IP address consists of 4 groups of numbers seperated by a dot [.], these numbers are limited to the range [0-255] where 0 and 255 have a special meaning. (0 decribes the segment as such and 255 is the so-called broadcast address)

IP addresses having a certain value for these groups in common define a segment.

 

there are 3 types - class A (first group is the same, network mask is 255.0.0.0), class B (first 2 groups are the same, network mask is 255.255.0.0), class C (first three groups are the same, network mask is 255.255.255.0) - there is actually a fourth type covering so-called subnets, but we don't care about them for the moment and focus on class C, which is the most common for us.

 

we also need to distinguish between public and private IP address ranges - public IPs can be routed across internet, private IPs not.

private IP address ranges are:

class A: 10.0.0.0 or 10.x.y.z where x, y, z is in the range of [0-255] or [10.0.0.0 – 10.255.255.255] - again: 0 and 255 have a special meaning

class B: [172.16.0.0 – 172.31.255.255] class C: [192.168.0.0 – 192.168.255.255]

independantly from the IP address range we are in we use the class C network mask [255.255.255.0] which defines a segment of 254 computers (or other devices)

there are other IP address ranges used by microsoft and apple (also called private) for autoconfiguring NICs, but we dont care about and cover that.

 

we need to define two more terms:

WAN (Wide Area Network = internet) with public IP addresses

LAN (Local Area Network = your or someone elses internal network) with private IP addresses

 

the interface between both is a ROUTER, a device which routes traffic from one network (segment) to another, in most cases from your LAN (private network) to the WAN (internet) - this device has an external IP (in most cases within the public range) and an internal IP (always within the private range).

the device itself functions as GATEWAY (the *door* network traffic has to pass on its way to another segment) - now network traffic as such is *dumb* and always needs a clear definition of the door, so never define 2 gateways or routers if you have more than one NIC in your computer unless you know exactly what you're doing ....

 

example:

router external address = 212.24.125.70 (WAN), router internal IP = 192.168.1.1 (LAN), LAN network mask = 255.255.255.0

(remember: 192.168.1.0 describes th whole class C network, 192.168.0.255 describes the broadcast address for this network)

computers (and other devices like network-printers) can now have an IP address within the range 192.168.1.2 - 192.168.1.254 and the gateway (or router) has to be set to 192.168.1.1, of course the network mask has to be 255.255.255.0 on each device.

 

many routers have the capability to assign IP addresses automatically using DHCP (Dynamic Host Control Protocol) if the computer is configured respectively (network settings) but i wouldn't recommend that for an audio network - as the term says: it is dynamic and we would of course prefer a static situation.

just make sure the network interface which should communicate with the internet (via the router) is in the same IP address range as the router itself. all traffic aiming a public IP now knows which NIC and *door* it has to use ...

one step is missing now: DNS (= Domain Name System) entries, who are responsible for resolving names (like vsl.co.at) to IP addresses.

usually you have 2 of those entries (if one DNS server goes offline) and the respective IP addresses depend on your provider.

many routers and network settings allow to assign these DNS entries automatically but you might need to set them manually when using static IP addresses for your computers.

 

 

now back to the 2-NIC setup .... we already know both need to reside in a seperate segment (otherwise traffic wouldn't *know* which of them is the *door* to the world and which to the SLAVE)

example:

NIC #1: IP 192.168.1.2 mask 255.255.255.0 gateway: 192.168.1.1 DNS according to your provider, cable connected to the router

NIC #2: IP 192.168.2.2 mask 255.255.255.0 no gateway, no DNS needed, cable connected to your SLAVE computer

 

NIC #3 (on the SLAVE computer): IP 192.168.2.3 mask 255.255.255.0 no gateway, no DNS needed, cable connected to your MASTER computer

of course the cable can be either connected directly or via a switch, but do not *cascade* switches

 

on the MASTER connect VE 3 now to the SLAVE (192.168.2.3) after having started VE 3 service on the SLAVE ...

each network packet on the MASTER now knows where to go - to the slave it is using NIC #2, to vsl.co.at it is using NIC #1

the most complicated part of the job is to find out which jack on your computer is NIC #1 and which NIC #2 ;-)

 

hth, christian

[benbartlett]

Hi Christain,

Thanks for that comprehensive information.

However, could you explain this in simple terms?

Are you saying that if I have the following configuration:

Master Mac (DAW) has Ethernet Port 1 connected to a router, to access the internet and other (non VE) macs on my main network.

Same Master Mac has Ethernet Port 2 connected DIRECTLY to Ethernet Port 2 of Slave Mac (or optionally, via a Gb switch to allow further slaves on this LAN).

Slave Mac (optionally) also has it's Port 1 connected to the same router (ie network) as that of Master Mac's Ethernet Port 1. This is mainly to allow software udates and library pool operations to be carried out on that Slave. Indeed it would also allow Apple Remote Desktop to fuinction too.

Now, this is the PHYSICALL configuration I was assuming would work (which I have not tested yet). My thinking was that both Macs would have Appletalk enabled on their respective Ports 1. This would allow my current netwrok requirements to still be met. My thinking continued, that Ports 2 of these two Macs would not require Appletalk (as VE does not require it) and therefore the Vienna Service instantiated on the Slave would be detected by the Vienna Server Plugin on the Master Mac, and would be detected it automatically via the Ehternet Port 2.

I get the feeling you are saying that this is not the case?

Do I undertstand you right? 

Thanks,

Ben Bartlett. 

[cm]

@benbartlett said:

However, could you explain this in simple terms?

this have been the simple terms ... 😉

if i understand your configuration right it works. example:

Mac #1 NIC #1 (network #1) [192.168.1.2] -> to router

Mac #1 NIC #2 (network #2) [192.168.2.2] -> cable to Mac #2 NIC #4

Mac #2 NIC #3 (network #1) [192.168.1.3] -> to router

Mac #2 NIC #4 (network #2) [192.168.2.3] -> cable to Mac #1 NIC #2

all NICs have netmask 255.255.255.0, only NIC #1 and NIC #3 have a gateway [eg. 192.168.1.1] and DNS server entries

what we noticed in such a config is, that not always the SLAVE's announcement is automatically seen by the MASTER and connecting to the SLAVE needs the IP entered manually (this behaviour seems to depend on which network the SLAVE assumes to be the primary)

appletalk and sharing not needed to be bound to NIC #2 and NIC #4 - works using TCP/IP only

christian

[benbartlett]

Hey thanks again. It's Sunday isn't it? I see the problem - the situation is not as simple as immediately apparent. In a nutshell, the VE Service is NOT automatically detected. One question: why do the two NICs on my "Port 2" network need to be the same model? They probably are as in my case, luckily, I have two Mac Pros that are within 3 weeks age of each other. However, I may also introduce a PC. This would be a problem in that case. I am going to actually test this and see what happens, at least between my two MPros. Sorry to keep probing you for knowledge. I understand a little about networks (I have set up 6 Macs together using 10.0.0.0 addressing, with an Airport Extreme distributing the addresses, whilst IT is given another address by my internet router - technically illegal) but am no wondering this: To follow your "rules", I should manually set up IP addresses and subnet masks for the Port 2 side of things. Is this right? Thanks. I am going to give it a go.... gulp.

[cm]

ben, my note regarding the two network cards having to be the same is referring to the posting from MS above mentioning *teaming* (= connecting 2 network cards on the _same_ computer to the _same_ network to double speed from 1 Gbit to 2 Gbit) - this is independant from the situation i described below, which is called *multihomed* (= 2 network cards in the same computer are connected to seperate networks)

 

!! do not try to configure teaming if you are not very familiar with networking ... ask your network administrator for help !!

 

back to your situation: you're in the network range 10.0.0.0 - basically no problem, as long as you stay with network mask 255.255.255.0 - so splitting your private classA network into classC segments ... the problem would begin, if your airport is distributing IP addresses based on network mask 255.0.0.0 ... then every device is within the private classA network and no seperate routes can be defined (and you are not allowed to give your two NICs in a single mac an IP address within the range 10.0.0.0)

 

an example that works (a little bit advanced):

say your DHCP server (which is in your case the airport) distributes IP addresses between 10.0.0.0 and 10.0.255.255 with a network mask of 255.255.0.0 (note: the second group in the IP is always 0 and the second group of the mask is 255) - this means splitting a classA network into classB segments

Mac #1 NIC #1 (connected to network #1) - leave on DHCP and receive some IP, say 10.0.0.2, mask 255.255.0.0, DNS auto

Mac #1 NIC #2 (connected to another mac's second NIC) - manually set to 10.1.0.2, mask 255.255.0.0, no DNS

Mac #2 NIC #3 (connected to network #1) - leave on DHCP and receive some IP, say 10.0.0.3, mask 255.255.0.0, DNS auto

Mac #2 NIC #4 (connected toNIC #2 of the mac above) - manually set to 10.0.1.3, mask 255.255.0.0, no DNS

 

as mentioned above VE 3 on your Mac #2 (the SLAVE) might announce itself to the *wrong* network, but in any case you could connect from your MASTER (Mac #1) manuall to your slave (= 10.1.0.3) - given the cable is connected and firewall does not block.

 

make a little drawing for yourself to visualize the situation, use the network utility to double check the general connectivity (ping)

 

i'll provide some screenshots later, but unfortunately the last OS X update disabled my grafic card :-/ and i didn't find the time to repair it ...

christian

 

 

[cm]

@benbartlett said:

whilst IT is given another address by my internet router - technically illegal)

not neccessarily .. there are more possible options which oi didn't cover to keep confusion on the lowest possible level 😉

 

but: if you have an IT department ask them for help - again prepare a little drawing what connections you'd like to have to make your needs clear, i'm sure they can find a configuration which fits your needs ....

 

you could actually put your second NICs manually into the 192.168.0.0 range to avoid the *salad of numbers* from my previous post ...

christian

[benbartlett]

Hi There,

I have proudly created a screenshot of my achievement but don't know how to attach one in this forum.

My success in words:

On  Port 1 - my network settings have remained unchanged, and I can file share, stream video, browse internet etc etc accross about 6 macs, some of which are on wireless extensions of this Gb network as I could before.

On Port 2: Successful instantiation of VE3 (as slaves) on 2 separate MacPros, controlled from my G5 daw machine. All done via manually setting up IP addresses in the range 10.0.2.x, starting of course as per your advice, with 10.0.2.2 and working up from there. This is all via a Gb switch by the way. In effect, 3 Macs on a completely separate network from the one upon which they connect for other purposes.

I chose his range as it seemed "safer" as the Port 1 network range is of the same class (ie 10.0.1.x). However, I am sure you would tell me that it wouldn;t have mattered if it was 192 addressing. 

And it works! I have confirmed audio being received and midi sent. 

Many thanks for your advice. I may have been lucky of course, in that I am marrying 2 very late Macs and one slightly older G5.  I won't attempt a PC connection for now....

Ben Bartlett.