Guidelines for Slow Site Connection

Hypothesis

One or several end users complain about a slow access to all applications (both in and out the LAN).

Diagnosis

You will find in this section the classical information to grab in order to diagnose the issue:

• Is the application really slower for this site? You can get this information from the Application Performance Dashboard.
• Does the slowdown occur for a specific application? If so, check Slow application.
• Does the slowdown occur for a specific server? If so, check Slow server.
• Did you upgrade the clients workstations recently? If so, it’s a specific system issue. You may ask the System Administrator for more details.
• Did you upgrade your network equipment? If so, the router/switch configuration is probably involved.
• We may do an in-depth inspection of the PV dashboards. Check the Monitoring -> Performance Over Time Chart
• Do the Retransmission Rate and Retransmission Delay vary? If so, we might face a congestion issue. Take a look at the router’s load, etc.
• The general slowdown for a client zone may also be the consequence of a crucial service: the DNS. Check out DNS Response Time.
• Look at the Monitoring -> Bandwidth Chart to inspect the bandwidth variation, and the number of TCP/UDP flows as well.

They might have overcome a QoS threshold, such that all new application requests are blocked. A hint would be the increasing number of TCP RST packets. To be sure, you may dive into the Analysis -> TCP Errors menu.