Newbie Question

cpremo · ‎03-13-2007

I'm not very familiar with proper switch configuration or management, so please forgive me for asking the obvious.

We are experiencing a lot of network slowdown. We have 2924-XL and 2950 switches. All our PCs are hard coded with Class C IP address (XXX.XXX.24 and XXX.XXX.25 IPs with subnet mask of 255.255.254.0). All the Switches are addressed in the XXX.XXX.24 range with same subnet mask. No VLAN has been configured.

Should we set all ports to Auto-Auto and all PC NIC cards to Auto?

What problems will occur if some are set to Full-100 on both ends?

We have set all switch port connections to Full-100 on both ends. Further, the port connection to our Router is set to Full-100 with the router configured the same.

We are seeing utilization spikes.

Richard Burts · ‎03-13-2007

Chris

This is a good place to ask this kind of question, though without a bit more understanding of the environment we are not likely to come up with the ultimate answer to your situation.

But part of it we can certainly address already. If switch ports are configured for auto-auto and NICs are auto then things should work. As a general rule both sides of a connection should be configured simimlarly: if one is auto then both should be auto and if one is hard coded then both should be hard coded. If both sides are Full-100 then it should be ok.

You ask a good question about whether it would be beneficial if you configure VLANs. With a subnet mask of 255.255.254.0 then you have address space for 500 devices. But we do not know how many devices you really have and that could make a difference. In general I would say that as a network grows it is beneficial to configure VLANs, especially if some care is given to arranging what devices go into which VLANs. If your usage spikes are the result of a small number of PCs on the network and those PCs were put into their own VLAN then the rest of the network would be somewhat sheltered from those spikes. But it would take some analysis to determine what is causing the spikes that you talk about.

HTH

Rick

HTH

Rick

cpremo · ‎03-13-2007

There in lies the main problem. I'm not sure where to go. But to start, we have:

1. Approximately 200+ PCs at our HQ location (Win XP and 2k), about 30 printers, and 18 servers (12 Novell NW6.5, 2 Novell NW 5.5 and 4 Windows 2000 and 2003 servers). There are 23 switches (2 in one subcloset, 8 in another subcloset and 13 in the master closet - the subcloset are connected via fiber).

2. Approximately 200 PC distributed through 12 field offices (Patial T-1 connected to main router. Comming through main port onto network. (Each field office has one or two switches)

All users access files on four of the servers, E-Mail on another server, and printers (we use Novell iPrint) on another.

Richard Burts · ‎03-13-2007

Chris

Are the PCs in the field offices in different IP address spaces or are they in the same /254 set of addresses? If they are in the same address space, it implies that you are bridging them in, and the first thing that I would suggest is to give them different address space and to route for them.

Given your description of the network I would think that it was probably good to configure VLANs. At a minimum I would suggest a VLAN for the servers, at least one VLAN for users, and a VLAN for device management traffic. It might be helpful to think about subdividing the users into several VLANs - perhaps one for each subcloset and one (or more) for the main closet. Configuring several VLANs would reduce the size of the broadcast domain. There is possible benefit if the servers are isolated from the broadcast traffic of the users and potentially benefit if users in one closet are isolated from the broadcast of users in other parts of the building.

Getting into more detail of how to assign VLANs may require more knowledge of the environment than we are likely to achieve on the forum.

HTH

Rick

HTH

Rick

cpremo · ‎03-13-2007

Can you point me towards any documents that will help me understand VLANs and how to configure them?