topic Re: Understand App_overrride in General Topics

Understand App_overrride

BigPalo — Mon, 24 May 2021 06:57:32 GMT

Hi,

We did a change from another vendor to PA. We realise that backups (vmware) were transferring very slow. So we created a app_override in order to avoid L7 in this VMware traffic. After that the spped for backpus got better.

So i have several qestions:

-Why is this happening? whats wrong L7 inspection does in order to slowness?

-what kind of traffic app_override can improve?

Re: Understand App_overrride

Remo — Mon, 24 May 2021 08:07:21 GMT

Hi @BigPalo

What PAN-OS version do you have installed?

Prior to the app override do you have also secirity profiles configured or only a security policy with app-id? Did you check global counters when the traffic was slow?

Re: Understand App_overrride

BigPalo — Mon, 24 May 2021 08:51:18 GMT

9.0.9 version.

We have a security rule permitting backups VMWARE ports.

The idea is to know whats wrong in order to use app_override.

Re: Understand App_overrride

Remo — Mon, 24 May 2021 10:58:09 GMT

First I recommend to upgrade to 9.0.13 which is the preferred releasd of PAN-OS 9.0. (PAN-OS 9.0.9 is almost one year old).

The issue might be some bug in app-id processing that some buffers are full and because of that packets are dropped which results in poor performance. Something like that you may see when you check the global counters (with proper filters for your backup connection applied). As you no diabled layer 7 processing the buffers aren't used and the performance isn't degraded. Obviously this is only an assumption as I don't know this issue in detail, but again, I recommend to upgrade and check again then if it may be already solved the issue.

Re: Understand App_overrride

BigPalo — Mon, 24 May 2021 11:58:38 GMT

What global counter flag should i keep in mind for this?

Re: Understand App_overrride

Remo — Mon, 24 May 2021 12:21:57 GMT

Which one exactly I cannot say right now, but with filtering for severyity drop and/or errors you maybe see values which increase during such a connection and this might be an indicator for a problem like the one I was talking about.

Re: Understand App_overrride

OtakarKlier — Mon, 24 May 2021 22:20:50 GMT

Hello,

Another thing to remember about app override is that the PAN will not scan the traffic for any malicious payload. So I would say you really need to trust that traffic.

Regards,

Re: Understand App_overrride

BigPalo — Tue, 25 May 2021 10:48:46 GMT

Yes we know. We just wanted to know what PA produce this slowness,