Switch to switch performance issues?

crazyswede

crazyswede

crazyswede

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We are moving to a new office I just need some advice on networking. Apart from the normal cabling to the rooms we have a big room which is going to have an island of desks with about 16 to 20 people. Should I run a cable, for each computer, from the server room switches or should I run a few cable to other switches under the island and distribute the cables from there. Will there be a performance it running from one switch to another, i guess there is? The distance from the server room to the island of desks is not that great.

crazyswede
 
Depends on the bandwidth needed. If they are only light users, then having them on their own switch is would be okay but they will be sharing 100mbit (assuming you don't have gigabit switches), as oppose to getting that amount each if they were all directly connected to your main switch.
 
I would probably put a decent gigabit switch under there and hope they just check there emails and browse the news and not start trying to copy hi def movies off the server. Then again I'm lazy like that, routing and terminating 20 cables if I didnt have to is a job I'd rather not do. Especially as 20 cables is quite a sizeable bunch, routing might be a pain.
 
Good switches will come with a minimum of two uplink ports.
You can use LACP (Link Aggregation Control Protocol) to link those two lines together, for extra throughput to that switch.

It means running two wires from the core switch but that's much nicer than terminating 16 - 20. ;)

The 'clean' way of doing it would be to run the 16 - 20 but it's far less hassle to do it like that.
 
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I can get people to make/help me terminate the cables :) The files being transfered will be quite big. There will be a lot of data tranfered and that does not include movies and stuff. Maybe a mixture might be the way to go; desktops with straight connections with sockets on the desk for laptops servered from a local switch. The sockets need to be terminated anyway :rolleyes:

There is no wiring at all yet.... no power, telephone cables or network cables....
 
If there is no wiring in at all at the moment, then look at getting the sparkies to lay the cable in for you as they will need to route power cables out there. (obviously make sure are seperated from the power)

That way you only have to get the cables terminated which shouldn't be that much work.

By the sounds of it will be big transfers so if they are used to Gigabit now, will likely complain if start sharing even 2Gb between 16-20 of them.
 
11 are sharing a switch now with 2 cables going to another switch and yes they are complaining :)

Its all fresh and so yes putting all the cables in would be easy in theory. I think in one way by having seperate cables would make it easier to look after and more flexible. Yes, I will seperate the power cables from the network cables :D
 
crazyswede said:
11 are sharing a switch now with 2 cables going to another switch and yes they are complaining :)

Its all fresh and so yes putting all the cables in would be easy in theory. I think in one way by having seperate cables would make it easier to look after and more flexible. Yes, I will seperate the power cables from the network cables :D
Click to expand...

Umm, how are you aggregating those links? You do know if you just plug in two cables you'll actually be killing performance by creating a broadcast storm right?

To be honest I'm always dubious when people say they need multi gigabit uplinks, I design and build service provider networks running tens of thousands of servers and most of the time we're not even using 10Gig on our WAN links, that's with 15,000 servers, so do you really need 2Git for a dozen machines??
 
2 cables and each cable goes to a seperate 8 user switch, so no collisions.

We are a marine survey company and we process a lot of data. Depending on what sort of processing a project can involve 100,000s of small files or 100's of 250MB files and I sometimes process 60GB files which has 500million points which I can use to make a 3d image of the seabed (I don't work over the network with a file that big :D). What I am trying to say is that it is not just word documents being tranfered.

I am just trying to get it right the first time. Well sort of :)
 
crazyswede said:
2 cables and each cable goes to a seperate 8 user switch, so no collisions.
Click to expand...

collisions aren't the problem, looping broadcasts between two switches is the issue.

If you really need performance (and you don't have a lot of users - which it sounds like) forget separate switches, the backplane speed of a decent switch will thrash any uplink you can afford (a Cisco 3750 has a backplane speed of 35Gbit/s full duplex...).

If you're processing files with that sort of number of data points then I'd double check your IO chain and make sure you've got no bottlenecks there first, you're going to need a very serious workstation to process that sort of data at a speed which troubles a gigabit network.

If it truly is the network that's the bottleneck then I'd strongly recommend getting decent advice, I design high end networks for a living and my considered advice is not to rely too much on answers on a forum ;)
 
Yes, you have to take what is said in this forum with a pinch of salt. However you can also get pointed in the right direction or even good advice by people who know like you. I will be seeking more professional advice on switch side, I was really more questioning the wiring on this occasion. I have probably answered my question myself.

It's a new build and not too large, therefore I am going to get all the network points wired to the server room. What happens there will be a mystery...

Thanks for the advice I have got so far :)
 
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