I was the headquarters of the environment, there are two lines can access and back up each other. My micro-channel network can not suddenly prompted me, and I was scared Ji Ling, do off the net.
Then I turn on the computer, it has been open a web page, domain name PING a public network, I go, unable to visit the. Then that is a bunch of people came over and asked not to be off the network, and feedback on this information to the entire company and hung up.
At that time, my mind wanted to think of a lot of possibilities, I could not even wireless WLC died, and WLC switch connected died, DNS server is dead, dead router, firewall dead, broken line . In this N number of possible conditions, if you want to debug, will make you too busy.
Fortunately, I have SolarWinds monitoring system, the first time to log on and see the firewall's external interface died. Although we set up a floating routing, firewall to hang up if the monitor will automatically go to another line, but still does not work, when the ball dropped the key, in my heart meditation many times N (omitting it)
Burst into the room immediately, restart the firewall, the problem is solved.
Experience: Problems occur, there must be monitoring tools, troubleshooting otherwise be too painful. Even the best design also does not work when the key or by restarting it.