sflow traffic denied from certain IPs even though rule allows it

[scott.jones]

I'm seeing an odd issue where I've got a rule allowing sflow traffic coming from a WAN zone into my server zone where my monitoring servers sit.  Most of the traffic passes as it should, but there are random subnets where the rule is being denied with it showing it is hitting the default deny policy.  The only filtering on the rule is for port 2055, coming from the WAN zone and into the server zone.  

Any ideas?  

[OtakarKlier · Accepted solution]

Hello,

Is the incoming sflow traffic on port 2055? The logs should show what is getting blocked, ie. source, destination, etc. Also I would change the policy to layer 7 by using the sflow application.

Cheers!

[BPry · Accepted solution]

@scott.jones,

Utilizing the 'test security-policy-match' command in the CLI with one of the denied flows should verify that the traffic should be matching your intended security entry. 

[scott.jones]

That ended up doing the trick.  Still not sure why some sites worked and others didn't, but when I switched to the app rule, it started passing traffic.

thanks again for the help!

[scott.jones]

This will come in handy for sure going forward.  ended up switching to the app rule for sflow and getting rid of the port-based config, and now it's allowing the traffic through.  

Thanks for the info!