Advice on troubleshooting high TCP retransmissions datasource

[Simon O'Sullivan 2]

Hi all,

This is not really a LogicMonitor question, more a general troubleshooting question.

I have a couple of windows servers we monitor that have suddenly started having about 30% TCP retransmissions.

It looks like the datasource is monitoring retransmissions that are TCP segments retransmitted \'\'to\'\' the server that is being monitored.

We have a couple of servers in different sites with the same issue. The servers are not under any particular load.

They happen to be all virtual servers running on ESX5 hosts, with Cisco switches.

We ran a packet sniff with wireshark and the retransmits seem to be coming from a range of servers on different ESX hosts, so unlikely to be an individual faulty switch or network cable.

Anyone looked at this before and have any ideas?

Simon