Always wanting to monitor more and more the things, I finally decided to get some sort of flow monitoring thingy going. The SolarWinds Real-time NetFlow Analyzer looked cool, and was pretty easy to get up and running. For our Juniper I followed these instructions
http://www.juniper.net/techpubs/en_US/junos13.3/topics/example/sflow-configuring-ex-series.html
Basically I used putty to SSH into the switch.
Type configure
[edit protocols]
set sflow collector 10.204.32.46 udp-port 5600set sflow interfaces ge-0/0/0
set sflow polling-interval 20
set sflow sample-rate egress 1000I also added
set sflow sample-rate ingress 1000
then type commit
Michael Ellerbeck 
What would you recommend to monitor crc, discard errors. We use solarwinds, just curious to know how users monitoring crc errors