SG 300-10's not performing as well as generic 10/100 switches over long cable run

[lbroering]

We have recently replaced three  - 10/100 Netgear or DLink switches at a customers site with three - SG 300-10 Gb switches. We are having a bandwidth problem with the connection between two of the switches. The customers says that the connection is slower than it was when we were using just the 10/100 switches. Here are the connection details -

The cat5 cable length is approx 374 feet (tested with cable tester and all wires are connected)

I have one end of network cable plugged in to port 10 on one SG300 and the other end plugged in to port 10 on another SG300. When I have the port settings set to "Automatic", I do not get any link light at all. When I set the one end to "100m Full Duplex", the switch at the other end shows that it sets itself to "100 Half Duplex", I get a link light and the switches pass network traffic between one another. Since 100 M seems to work, I tried to set both ends at 100 M full and 100 M half but have had no luck getting any better bandwidth than when one switch is set to 100M Full and the other is set to Auto.

The issue is that they were getting better bandwidth with the old switches.

Are there port settings that I can change so that these two switches will work better with one another at the 10/100 speed? I would think I could at least duplicate the speed they were getting with the cheaper switches.

[Sivaprasam Subramani]

Hello Ibroering,

First, Cat5 cable maximum recommended length is 100m (328feet). I see you site has 374 feet. To diagnose more on this issue - kindly provide the following information.

1.  Get me the speed and duplex settings on both interface (show interface G1/1/1).

2.  Kindly perform copper test and provide me the result (administration -> Diagnostic -> copper test).

3.  Kindly use ping utility to verifyt  reachability and latency.

Please feel free to contact me if you have any queries.

Thanks and regards,

Siva

[lbroering]

                   Thanks Siva

My results are attached in 2 text files. The remote switch is the one at the far end of the long cable run. The Middle switch is in the "Middle" of the network and is connected to another SG300 switch in the server room.

In addition to the attached files. I received this message during my telnet session to both switches -

switcha5eedb#09-May-2013 09:05:49 %CDP-W-DUPLEX_MISMATCH: Duplex mismatch detected on interface gi10.

Message was edited by: Larry Broering

Message was edited by: Larry Broering

[lbroering]

Update

After seeing that the Remote switch status was 10 M Half, I changed the setting on the Middle switch from 100m Full to 100M Half.

The Status of the Remote switch changed to 100M Half after I did this. I called the owner so that he can give me feedback as to whether this helped.

Would you expect that this would help?

[Sivaprasam Subramani]

Hello Ibroering,

Duplex mismatch might be the cause. Please update me the status.

Thanks and regards,

Siva

Please mark answered for helpful posts

[lbroering]

Sivaprakasam

I talked to the owner on Friday and he says that the bandwidth was faster with the old switches then what it is after I made the change so that the SG100's are working at 100M half duplex at both ends. 1 end is hard coded and the other end is set to auto. Are there any other ideas out there?

[lbroering]

                   I attached the configuration for both switches and other status, as of this morning.

When I ping a computer across the connection the latency is <1ms