Please join us on Sept 21 for our free monthly webcast! We will be talking about wireless network analysis.
BEWARE OF UNEXPECTED ROADBLOCK!! Server Backup over Gigabit – Why is it taking SO LONG?
Using Wireshark to expose delay issues!
Here is a quick little command line that you can use to capture all the DNS traffic seen by the analyzer:
tshark -n -i 5 -R ” dns.flags.response == 0″
Just replace the “-i 5″ with the appropriate interface for your analyzer. You can find out the interface numbers by using the following command:
If you want to get fancy, pipe this to a text file, or use a program such as klog.exe to send it to syslog. We have used this this in combination with Splunk to keep track of all the DNS queries. Splunk allows us to search the queries for specific data patterns. Great way to see when people are going, without a fancy proxy server.
Sometimes the most difficult part of isolating a network problem is getting a good capture. With Fluke Networks new Series III OptiView, we can capture at full line rate Gig and setup free string filters. However, none of this does us any good if we can’t stop the trace before the problem packets roll out of the buffer.
We have created a short video showing how to use the new Series III to allow the person experiencing the problem to stop the trace. Check out this video and see how to configure the OptiView to implement triggers. Even if you don’t have a Series III, it is worth seeing what this instrument can do.