topic Re: Slow internet performance behind PA-500 in General Topics

Slow internet performance behind PA-500

skiffsumner — Wed, 30 Aug 2017 05:27:42 GMT

I recently upgraded to a 250Mbps internet speed.

When I plug my laptop directly into the ISP router I am getting close to 300Mbps.

But behind the PA-500 firewall, I am getting around 80-90Mbps.

Firmware is 7.1.10 running in HA

What would cause this?

Re: Slow internet performance behind PA-500

Remo — Wed, 30 Aug 2017 06:33:07 GMT

Do you have threat prevwntion enabled?

Re: Slow internet performance behind PA-500

kiwi — Wed, 30 Aug 2017 06:44:07 GMT

Hi @skiffsumner

What debugging have you done so far ? This can be related to a bunch of things ...

What features are enabled on the device ? (see @Remo's previous reply).

Is the link status negotiated correctly with your ISP ?

Are you seeing lots of errors or drops in the global counters ?

Here are some links that can help you start debugging or some discussions that experienced slow internet :

https://live.paloaltonetworks.com/t5/Management-Articles/Troubleshooting-Slowness-with-Traffic-Management/ta-p/61805

https://live.paloaltonetworks.com/t5/Management-Articles/DHCP-ARP-and-Slow-Internet-Packets-Dropped-No-ARP/ta-p/60241

https://live.paloaltonetworks.com/t5/General-Topics/SLOW-INTERNET/m-p/41527#M30530

Cheers !

-Kiwi

Re: Slow internet performance behind PA-500

fjwcash — Wed, 30 Aug 2017 21:04:28 GMT

@Remo wrote:
Do you have threat prevwntion enabled?

This is most likely the issue. We ran into the same thing for our sites that have either gigabit fibre links or 120+ Mbps point-to-point wireless links. All our LibreNMS traffic monitoring graphs were showing almost flatlines at 100 Mbps throughout the day, and we could not figure out why.

Until we looked at the product details page for the PA-500. It's listed right there that Threat Protection is limited to 100 Mbps throughput. Any rule that has that enabled will limit traffic to 100 Mbps.

There's a few other limits listed as well (250 Mbps for application filtering, or something like that). The more in-depth the filtering, the slower the throughput. You'll only get line-speed filtering on the most basic of rules (port and protocol, basically).