Download slow passing through PA


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L3 Networker

Download slow passing through PA

Hi All!


i have this problem: when customer downloads, it is very slow, with isp he bypassed the PA device and it was faster.

I created a new rule without any security profile to verify if it was caused by them, but customer says it is the same (and it could be slower).


QoS is not enabled.


Do you have any suggestion about this problem? Some function to check?




L7 Applicator

Hi Daniele


you could check if there's possibly any fragmentation or MTU issues, you may need to enable TCP MSS if that's the case


if you set up a packet-diag filter (debug dtaplane packet-diag set filter ...)  and trace the global counters (show counter global filter packet-diag yes delta yes), you should be able to determine if packets are getting discarded or there are other issues (maybe packets are being received in an incorrect order, or fragmentation is being applied incorrectly,...)

Tom Piens -
New to PAN-OS or getting ready to take the PCNSE? check out
L2 Linker

Hi Daniele,


Another suggestion: check the stats of interfaces. Maybe you have a duplex problem which can lead to slowness... 

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