I have an issue at a client site with several different problems. The customer chiefly complains about intermittent slowness on the network. The slowness appears to come at random times, including during the evening when there is supposedly little network traffic demands. Here is a brief outline of the environment.
There are six Dell Powerconnect 3348 switches (48 ports each) that are linked via 100GB connections.
The internal network is running a Windows 2000 server which also contains the Exchange Server. We have isolated a great deal of traffic going to this server as it provides internal DNS for the company, and of course all the Exchange related traffic.
The firewall, a Sonicwall PRO 200, has multiple VPNs setup to approximately 8 remote offices. It also is the router providing the company with external internet connectivity and email traffic with a 1.5MB DSL connection. Connected to the firewall in a DMZ are several other servers, primarily a LINUX box which runs a heavily used application accessed from both the inside and outside of the network.
VPNs have been setup for home users using inexpensive Linksys routers.
Due to the demands on the network, little troubleshooting can occur which will or might bring the network down.
Here are the problems observed and reported by the customer.
1. Intermittent slowness of the application running on the LINUX box from either inside or outside the network.
2. Intermittent slowness of the network in general getting from workstations to any other internal server.
3. Intermittent slowness to/from internet.
4. Possibly related, but the router provided by the ISP seems to go down more frequently requiring a reboot. A second router was provided by the ISP, but was misconfigured, and the company is waiting on a third router to be brought and installed.
5. Slowness with VPN connections; I havent observed this myself, but it has been reported.
I suspect that the problem seems to be centered on the PRO 200. As an experiment, I would like to try to remove the LINUX box from the DMZ, isolate it to another network behind another router (using one of the many available IP addresses) and allow it to be observed for several days. Im hoping to see if the next round of slowness effects access to this server.
Im hoping to get additional suggestions or advice as to how to best troubleshoot these problems. Because of the multiple nature of these issues and the amount of work which may be required to resolve the problems, I am assigning 500 points to this question.
Thanks
