Whats the best network setup with this hardware

[handyman]

Hi Guys,

Sorry I've not been on much lately but work and play have been pretty full on this year.

Having a few issues with our work network and I figured I would see if a reconfig of the network layout might help things.

We have a Microwave broadband connection that is 10mb down/2mb up. This comes into a netgear firewall router with 4x 1gb ports.

We have a 24 port switch that also has 2x gb ports.

Plugged into the switch (100 port) is a linksys adsl router that handles our voip calls (thru qos).

The switch goes into a patch panel and round the office to ethernet sockets.

We have a sbs 2011 server (dhcp, exchange) plugged into a 1gb port on the main switch and the other 1gb port on this connects to the netgear firewall. We also have a wireless access point plugged into a 100 port on the switch.

The problem I think we have and I'm trying to eliminate is a user that prints very large ppt files over the network killing our bandwidth. Previously I had him connected from the patch to the netgear and had set up a print server sharing the printer (connected on usb) so that it came out of the patch and into the netgear.

I removed that as was told it was a loop. (seemed to be working fine though).

So Finally to my question. Which way would be optimal to connect things up?

Cheers
Mark

[Uncle Peter]

Don't think there's anything too shabby about the way you have it setup at the moment. I'm wondering if you have some kind of aggressive re-transmission issue when someone tries to offload a large file onto that print server either due to a problem with the print server itself dropping traffic or a physical cable fault. Also, PDF files, particularly large ones can be particularly troublesome on certain types of printer.

I would check your print user's NIC stats for retrans/errors or maybe run Wireshark for a wee while, also look through your print server logs if they are supported. Might be worth popping your trunk cables onto a fluke if you have one or swapping them completely if it's not too much hassle.

...forgot to ask, is your switch managed and does it support snmp so you can pull some stats off?

[MovedGoalPosts]

Is it the network bandwidth or actually the print server function causing the issue? I'd be looking at the print server, especially if the files are very large. Is the USB server capable of properly buffering the data and note it may only be operating at 10meg speed?

We run a SBS2003 network with some 19 users. Only in the last few months have I upgraded our switches to gigabit, before then everything was at 100meg speeds. I never saw a bandwidth issue. In fact our real slowdown was due to a database system that the workstations can't really handle. Even so we have 7 or so printers, all of which are ethernet connected with the server doing all the active directory stuff for those. Only one printer is USB and that is hung directly off a workstation so the workstation would act as the print server even though that printer is then shared across the network.

Can you try hanging the printer directly off a workstation, or even the server itself and get rid of the USB print server? If that proves to be the issue then look at getting a printer with an integrated network card.

---------- Post added at 14:36 ---------- Previous post was at 14:25 ----------

How do you ensure the data traffic is going through to the correct router i.e. netgear firewall or the VOIP thingy. Is there a chance that stuff is bouncing though one before it hits the correct one? What is actually controlling the QoS / load balancing routing rules?

I'm not sure from your diagram. Is the top row of connectors a patch panel as I can't see why you would have a connector to that as well as the switch

SBS2011 is different to my SBS2003 setup as our server has two network connector, one to the Internet, the other to the office network switch, so our server does the routing, DHCP and firewall stuff for the workstations. Perhaps with the data flowing around your network, especially the added VOIP traffic, an upgrade of you swithc to gigabit might add extra capacity?

[Welshchris]

I have a microwave broadband setup to. I can cook my chips from the bedroom now :-D

[Dai]

Wouldn't the quickest and easiest fix be to give him his own printer?

It's got to be more cost-effective than rebuilding your whole LAN.

[MovedGoalPosts]

Originally Posted by DaiNasty

Wouldn't the quickest and easiest fix be to give him his own printer?

It's got to be more cost-effective than rebuilding your whole LAN.

which is why first thing I'd plug the USB into a work station (probably that users) and see what changes that makes.

Longer term would be to look at the general bandwidth i.e. gigabit switching, as well as true network printers (if you are buying / replacing), but also to understand that the routing is working efficiently without duplicating bouncing traffic.

[handyman]

Originally Posted by Rob

Is it the network bandwidth or actually the print server function causing the issue? I'd be looking at the print server, especially if the files are very large. Is the USB server capable of properly buffering the data and note it may only be operating at 10meg speed?

I've tried printing over the network direct to the printer (It's a large Kyocera - think photocopier size).

Can you try hanging the printer directly off a workstation, or even the server itself and get rid of the USB print server? If that proves to be the issue then look at getting a printer with an integrated network card.

I've tried setting up a slave machine connected via usb to the printer and getting the user to vpn so no print data hits the network. The ppt files seem to spool to 1.5gb

How do you ensure the data traffic is going through to the correct router i.e. netgear firewall or the VOIP thingy. Is there a chance that stuff is bouncing though one before it hits the correct one? What is actually controlling the QoS / load balancing routing rules?

Erm Pass, not sure how that all works.

I'm not sure from your diagram. Is the top row of connectors a patch panel as I can't see why you would have a connector to that as well as the switch

Correct it is a patch panel.

SBS2011 is different to my SBS2003 setup as our server has two network connector, one to the Internet, the other to the office network switch, so our server does the routing, DHCP and firewall stuff for the workstations. Perhaps with the data flowing around your network, especially the added VOIP traffic, an upgrade of you swithc to gigabit might add extra capacity?

We have just migrated from an older 2003 server to a brand new 2011 server, this has had zero impact on the issue. We used to have dual network points in the old server at one stage and ran ISA I think.

Originally Posted by Uncle Peter

...forgot to ask, is your switch managed and does it support snmp so you can pull some stats off?

The netgear supports snmp but I have been unsuccessful in configuring software to get stats from this.

---------- Post added at 15:07 ---------- Previous post was at 15:05 ----------

Originally Posted by Rob

which is why first thing I'd plug the USB into a work station (probably that users) and see what changes that makes.

Longer term would be to look at the general bandwidth i.e. gigabit switching, as well as true network printers (if you are buying / replacing), but also to understand that the routing is working efficiently without duplicating bouncing traffic.

Printer is too large/noisy to have in the same office as the user.

The network traffic is what I supspect. A few times during the day it will stall and our bb provider have been very helpful in stating that the problem is being caused internally. I actually believe them with this as they are a smallish firm and I have been able to speak to proper techs that configure their whole service.

[MovedGoalPosts]

1.5GB is a very big file. In turn that will take a lot of processing. Either the printer itself or it's print server will need a lot of memory to be able to handle that sort of size or it needs to be run through a robust computer that can do the buffering job. With that sort of file size regularly occuring I'd want the user to be able to dump his print data to whatever serves the kyocera quite quickly and for that data not to be coming back out again into the network. That means the kyocera being directly connected to the print spooler. I'd be speaking to the printer supplier to ensure the printer itself is configured optimally for that sort of file size. At 10Mb for tha average printer connection it's going to be shifting a 1.5GB file for some time. Although at 10MB that should still leave room for loads of other traffic.

Unless the printer is connected direct to the user's computer so he can print direct, traffic will be hitting your network with every print operation. That will be whether the printer is connected direct by ethernet to the network (and thus uses one of the computers or server as it's spooler service), or to a print server (specific networking device for the printer only). VPN is just a data connection method, it still passes over the same wires in your network to connect the workstation to the print server/spooler.

[Dai]

That's an interesting though. Presumably an image of the print job has to be built up somewhere before printing can begin. Where does that happen?

Is it in the printer's memory, the printer server or the spooler process in the server?

I'd like to understand how it works, and that could have a bearing on why it hits on the system so hard.

[Uncle Peter]

Originally Posted by DaiNasty

That's an interesting though. Presumably an image of the print job has to be built up somewhere before printing can begin. Where does that happen?

Is it in the printer's memory, the printer server or the spooler process in the server?

I'd like to understand how it works, and that could have a bearing on why it hits on the system so hard.

On disk and in memory on the client pc via the client spooler service to the print server's memory which will in turn perform a similar process to the client pc and stream the job via it's own memory and spooler service to the printer's memory buffer.

When the spooling job becomes larger than the print server's memory may well be where the problems start to occur and as Rob mentions above the OP would probably be best served depolying a server based print server with a suitable amount of memory. Whatever the OP's print server is doing to deal with an amount of data it can't buffer may be having unpredictable consequences on the LAN.

Also, when the job is translated into something the printer can understand (PCL, PostScript etc) the actual raw amount of data sent to the printer can be very large indeed, much larger than the actual size of the file on disk storage.

[haileris]

The absolute easiest way would probably be to buy another switch, plug that user / printer into that switch and multi-home the data server into that switch assuming he needs access to that. So that user's access to that server is via a dedicated line in effect.

Otherwise, use VLANs to segment the traffic and either set his subnets QOS lower?

[handyman]

At present the printer is shared via our main server (which is brand new 2,8 quad xeon with 8gb top draw server memory and boat loads of super fast hd space). When I say shared I mean it is on the network but the driver sharing is done thru the server.

Kyocera in all their helpfulness could not help with the setup over the network as they don't support that (go figure). Our printer supplier also was no help. There are 4 drivers available for the printer but nothing to say which one is the best to use..

[MovedGoalPosts]

In which case you are probably compounding the traffic on your network.

Workstation creates print file. That gets sent to your main server which spools and queues it. That then gets sent to the print server before it gets to the USB connection. It's very unlikely that your brand spanking new server is the problem.

What is the print server hard ware? Can you connect the printer direct to the server without the print server thing or alternatively direct to the the user's workstation. If you can't do that then I'd be looking at getting an older computer networking that and connecting the printer to that computer, sharing the printer from the computer rather than the server.

But for a couple of hundred quid look at upgrading your main switch to gigabit. Even without a change to your network cables assuming they are cat5e, most of your workstations will be able to pass other data to the server faster, thus giving you more bandwith.

[Matth]

The odd thing, a switch with gigabit backbone connections, should be able to handle several 100 megabit streams going port to port without interference, and 100 Mbit stream contending for the backbone should not be a great problem either.

[Matthew]

Does the printer have a network interface on it?