At 10:50 AM 2/19/2009, Hans van Staveren wrote:
>While figuring out the (slightly disappointing) performance from some
>Windows file servers in a corporate environment I found some TCP
>retransmissons using wireshark. Looking at the 'netstat -s -p tcp' output
>from the servers themselves I found a TCP segment retransmission rate of
>about 1%. My feeling is that this is a lot, given the fact that the whole
>network consists of three Cisco switches and two pieces of fiber.
>
>1) Is my gut feeling right about 1% retransmissions being a lot in this
>environment?
>2) The server guys told me they were using the HP teams driver on the
>servers, and that they heard that this would be a problem with Cisco
>switches. This does not ring any bell with me.
Others might have already chimed in, but 1% packet loss on a three switch network is pretty high.
Are you sure you don't have a duplex mismatch? Rule that out first.
hsb