4 Replies Latest reply: Jan 28, 2010 10:05 AM by tnewshott RSS

    Want to clarify switch uplink port question


      Say you have a switch with 12 100mb ports and 1 1gb uplink port. We have 11 hosts and 1 server all connected to the 12 100mb ports. Bandwidth begins to become an issue with too much server interaction (this is all hypothetical). Is there a possibility that the bandwidth bottleneck of the server could be eliminated by switching the server over to the gig uplink port assuming the server has a 1gb nic ? All PC's and server in the same subnet and vlan.


      If I need to clarify anything please let me know.

        • 1. Re: Want to clarify switch uplink port question

          What I meant to say is access to the server and server interaction slows to a crawl. This is not a web server, but a server used to share files and share one hotel check in/customer service application amongst the 11 hosts. Would this slow access performance to the server be eliminated by moving the server to the 1gb uplink port ?

          • 2. Re: Want to clarify switch uplink port question

            Maybe yes, maybe no.  In theory, it makes sense that increasing the bandwidth would improve performance, but that is only the case if the 100mb connection is indeed the bottle neck.


            Is the server and the switch negotiating 100/full connectivity?  Are you seeing errors on the server port?

            Do you see the slow responses from the server if only a few hosts are online, or does it require the majority to be online simultaneously?

            What do the counters and statistics look like on the server port?  Does it regulularly show over-utilization(anything over 65-70% average utilization IMO)?

            What does the CPU look like on the server during these periods of poor performance?



            If the switch is not uplinking to anything else, and just hosting these 10 devices and the server - then switching to the uplink is certainly a possible troubleshooting step.  However, if you have to break your uplink, it's not terribly useful, unless you do not send or receive much traffic on it.  At that point in time, you are just shifting your bottleneck.



            Is this a Cisco switch - or a consumer-grade type device?  What model, etc.

            • 3. Re: Want to clarify switch uplink port question

              I think you helped answer my question. Get a beefier switch. I'm still learning that all 100mb swich ports are not created equal. It was a consumer grade switch not a cisco switch. This also helped me understand that an uplink really should be mainly used as a trunk port.


              Thanks for the help

              • 4. Re: Want to clarify switch uplink port question

                Michael, glad I could help.


                Something to consider, is there is a reason that Cisco gear is expensive compared to consumer grade.  Better circuitry(and much more of it!), better performance, and more functionality.  You really do get what you pay for in some respects.


                For your needs, you could probably get away with an old 2950 or a 3550 and not be out much money, but still get a superior device over consumer gear.  Sure, you are lacking the warranty, but the price reflects that.  Another option would be a base model 2960, they are quite affordable as well, in the grand scheme of things.


                There is a grey area between enterprise gear and semi-managed consumer gear, and those are managed business-class devices built by Linksys and NetGear and other companies out there.  I do not mess with them very often, so I cannot speak to them, but they may be worth investigating if Cisco turns out to be outside of the current budget.