SPAN and Ingress traffic on 3750

Not sure I understand the question. Ingress means that the span port will also receive regular frames for the access vlan that the span port is in I think. Generally, you don't connect to the sniffer via the same port that sniffs, its a receiving port only (or should be). You use a management interface or second NIC to control the sniffer. So even if the ingress did work that way, you would have to configure an IP on that NIC in that VLAN. Could work, but I've never heard of anyone using a sniffer that way.

linguafr,

Trendkill is right... allowing ingress will allow the switch to receive traffic from the attached "sniffer." However, it looks like you've spanned the whole VLAN onto an interface. (albeit a gigabit one) Traffic from your host may be making it onto the switch - but it may not have enough bandwidth to receive any responses. Try the same span, but span only one interface (not a trunk port) on the VLAN - see if your "sniffer" works. Also, check the port utilization while spanning the whole VLAN.

By the way, Trendkill - I've used that method in the past - when I absolutely had to. It works as long as you don't overwhelm the link. Good Luck.

-JC

I have used Ingress frequently however I have found that it does not seem to actually work on all platforms. More modern ones dont seem to work.

I think that I have found that it did not work on

May of course be software and other hardware dependent.

I have formed the view that it works on older stuff and not on newer stuff.

The documentation and command line say that it works. As far as I can recall.