Wireshark-users: [Wireshark-users] TCP retransmissions from Windows file server

From: "Hans van Staveren" <sater@xxxxxxxxx>
Date: Thu, 19 Feb 2009 15:50:29 +0100
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.

Any help appreciated.

Hans