artnet delay reply

Hi all,
i need help!
i'm using 2 gMA , main and spare for controlling in artnet 4 macpro catalyst
2 main and 2 spare,
im using 2 simple switch lan netgear, one for the 2 consolle FOH
and the other one for the 4 macpro under stage

sometimes the catalyst give a reply with some second of delay !
for exemple if i increase a fader after 3 or 4 second something change in my catalyst
and sometimes all the communication slowdown,
it depends for an incorrect network setup?
im using 150mt. cat5 cable, is too much?
can i find some specific guide?

and
if i connect another lan cable for file transfer and remote desktop
the communication slow down and sometimes crash
can someone help me please
thank you very much

regards
Nicholas

There are a number of factors that could affect this:

- network switch
- network data
- cable length

Network switch
Ensure that the switches can support broadcast data.
Unmanaged switches are the best to use - cheap netgear / linksys / tplink are usually ok. managed switches can filter broadcast packages and may not work well

Network Data -
best to use a separate network for Remote desktop and file transfer - as this WILL slow artnet down if on the same network.
Do you have other artnet devices on the same network?

Cable Length
This might be a factor - but test the other 2 options first.
The only way to test is to use a shorter cable with the same network setup and and see if it makes a difference - this may mean temporarily moving the desk nearer the servers if possible...
You could also look at getting a fibre link between your locations. there are a number of switched that have a fibre port and thus avoiding any cable length issues.
however - I've run 100m cat5e networks with no issues... so do check the other possibilities first. (cat 6 may help?)

Also try UNICAST artnet from the MA2 rather than broadcast, as this will reduce the amount of data... although, this may not work for your main/backup scenario...

Best to remove all other devices from artnet networks and use a separate network for remote desktop and file transfer.

Simon

Simon has pretty much covered all the bases.

Although I would add that, I have seen this situation quite a few times before and it tends to be the switch, particularly when there are more than 1 in the system. 20 minutes of A/B testing will soon show if that is the fault(which I suspect would be the case). Dell switches are particularly troublesome.

Yes using Apple Remote desktop is very useful during rehearsals, but always have it running on the secondary network, and always turn any form of sharing off during the show. I would also mention that the web browser control is very good for a lot of catalyst remote duties(just not file transfers) and I use it pretty much every day.

And the ethernet side of things Cat5 and 6 technically are only good for upto 90m, without the signal needing refreshing. And anything over 100m I try and always use Fibre as it makes life so much more reliable.

Phil
Philip G Haynes
Live Visual Design and Direction

Nicholas,

150 mt Cat5 will cause network instability, If you move the switch for the understage machines to the 100 mt mark, and then extend 50 mt to each machine, your issues will likely go away.

The fiber method mentioned by Phil is an excellent option.

http://en.wikipedia.org/wiki/Category_5_cable is the Wiki on Max Cable Length.

Hope this helps.

I agree with the other chaps. 150m really is too long. Sometimes on a good day with the wind on in your sails and God on your side you can get a bit longer than the 100m limit, but I wouldn't risk a show on this. As Phil points out, in practice it is wise never to make your cables longer than 90m.

Fibre optic is never a cheap option mind you, and there are scenarios where fibre just isn't appropriate.
I tend specify and use Cisco switches and GIBCs out of force of habit. A fibre capable Cisco SG-300 series switch is good value, and you can get POE variants. You can buy made up LC-LC fibre pretty cheaply. I have tended to use 4 way fibre with Stratos connectors which allows 2 gigabit networks (Artnet and Catnet). On shows I've done recently I've added an extra 4 way fibre using LACP between the switches for a bit of redundancy. Nothing like a fork lift running over your fibre line to ruin your day...

Hugh