Great point - a small note though, for those of us who don't like using other people's hosted services and have some of our own infrastructure to host - use Zabbix, Nagios, Cacti, Spiceworks, Munin, PRTG, etc. Lots of nice options. I know everyone loves cloud services these days, but I feel absolutely no temptation to put any of my business infrastructure in other people's hands when I don't absolutely have to.

I use a combinations of Zabbix and a very agressive Smokeping mesh deployed with docker (10 pings per minute from all separate DCs all other DCs) to monitor our worldwide nodes and be able to account for routing problems on the backbone rather than our nodes themselves. Very handy tool, particularly if you work with latency sensitive applications. I've been surprised some of the datacenters we use appear not to have access to similar...