Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

Slow Transfer using Fiber

I am having problems with my tranfer from a virtual server to clients. clients to server speed is exceptable. I am running Fiber from the virtual machine to the Catalyst 3560 port both set to gibit auto. see attachment for show run and show interface. I am thinking I am getting a bottleneck becuase everything else on my network is running 100 duplex. but the speeds I am getting coming out the virtual server is only like 30-50 mbs going in is 100 + mbs

Hall of Fame Super Silver

Re: Slow Transfer using Fiber

Your "show interface" command output seems to have gotten garbled in your attachment. It should read something like:

Switch# show interfaces gigabitethernet0/2

GigabitEthernet0/2 is down, line protocol is down

Hardware is Gigabit Ethernet, address is 0009.43a7.d085 (bia 0009.43a7.d085)

MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec,

reliability 255/255, txload 1/255, rxload 1/255

Encapsulation ARPA, loopback not set

Keepalive set (10 sec)

Auto-duplex, Auto-speed


A duplex mismatch is possible but unlikely with Gigabit Ethernet fiber interfaces. The duplex command is not supported on 3560 fiber interfaces. Can you set it to forced full-duplex on your server?

Given that it's a virtual server, it may be sharing network I/O with other server instances on the physical machine. Might they be preventing that one instance from achieving its potential? Can you isolate the operations and run a utility such a s ttcp to check the theoretical maximum? See the following link for tips on using ttcp:

Hope this helps.

CreatePlease login to create content