I have 2 sites connected via FO link. Some servers locates in one site, the others in 2nd site.
Sometimes i have network corruption (like mail client can't reach mail server during synchronization, and after 2-3 seconds it can).Lost ping echo-replies packets 20% from some servers. How can i monitor, tests, diagnose the network links ? At first i am interested how can it be checked on Cisco equipment without additional softs(sniffers), tools? What is the general practice in the worldwide?