topic Re: Web Application intermittently having a performance issue in General Topics

Web Application intermittently having a performance issue

afifdin — Tue, 20 Apr 2021 16:31:23 GMT

From the tcp dump at the server end, I am seeing a lot of traces on TCP Dup ACK, retransmission and out of order being flag out at the pcap file

The connection made is via VPN client to the Web Application server. Tried few scenario where we access directly bypass the PaloAlto firewall and we don't see this traces on tcp dups and retransmission. For now the asymmetric routing is not the case. I'm suspecting something need to be tweak at the firewall either adjusting the MSS or disable server response inspection (DSRI)

Is there any other useful tips on how to ensure less tcp dups and retransmission would occurs if the request made by the client need to pass through Palo Alto firewall?

Re: Web Application intermittently having a performance issue

reaper — Thu, 22 Apr 2021 08:11:27 GMT

were you able to capture ngress and egress on the firewall, and trace the global counters at the same time? that may shed some light on what's going on

some of those Lenghts seem very large, are you allowing jumbo frames ? You could set TCP MSS to lower the payload

you mention asymmetric routing, how are you sure that is not the issue?

Re: Web Application intermittently having a performance issue

nikoolayy1 — Thu, 22 Apr 2021 14:25:37 GMT

You may check globalprotect logs for keepalive issues:

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000PPgZCAW

The other thing is check for MTU issues:

https://live.paloaltonetworks.com/t5/globalprotect-articles/troubleshooting-globalprotect-mtu-issues/ta-p/384894

If you have a newer version of the firewall 9.1 or newer or newer you can see the latency from the firewall:

https://docs-new.paloaltonetworks.com/globalprotect/5-1/globalprotect-app-new-features/new-features-released-in-gp-app/globalprotect-gateway-latency-reporting

Re: Web Application intermittently having a performance issue

ThomasNevil — Mon, 07 Mar 2022 19:18:04 GMT

Hello! I would like to say.... I am a student. First year... Learning all the disciplines and communication. Now Truth has recently started having difficulty with writing assignments in college. But already now I'm thinking about searching for a phd dissertation writing service. So far, the best thing to do is EduGeeks service. The writers are very cool and always come to the rescue despite the difficulties.