Seeing some random packet loss 3-12 hours at a time

PeterUK

FLEX 700H
V1.38(ABZI.0)ITS-26WK16-m11228

I'm thinking its linked to this
https://community.zyxel.com/en/discussion/31245/random-latency-handling-delays-on-flex-h-at-low-bandwidth

due to how many FQDN I have which can easily be trigged when in use by policy control but this time I have disable them policy control rules for them FQDN but I think the FLEX H still spoofs DNS queries and that this might be some background clearup running that causes this?

As the other issue is being looked into it might fix this issue

Zyxel_Melen

Hi @PeterUK

https://community.zyxel.com/en/discussion/31245/random-latency-handling-delays-on-flex-h-at-low-bandwidth

The discussion you mentioned will be enhanced in the future firmware release.

About the new case, may you share more details? We now are not sure what you mean on this part "I think the FLEX H still spoofs DNS queries". And what's the symptom about this issue?

PeterUK

hi Melen

So like all them policy control rules that would be used with all them FQDN I have are disabled but every now and then packet loss happens but its very random and long hours apart when it happens I can tell normally tell when its my connection or not.

When I say "I think the FLEX H still spoofs DNS queries" even without them policy control rules enabled for them FQDN the FLEX H still reads DNS queries and stores/updates FQDN objects but I think this time what might be happening is there is a TTL clean up process which might be causing the FLEX H to stall?

what I could do if needed is save my config remove many FQDN objects and see if it still happens?

Zyxel_Melen

Hi @PeterUK

Discuss with our team and we think you can keep the FQDN objects since we want to monitor this issue.

Just like previous case, please provide us a remote PC connects under the USG FLEX 700H with Teamviewer for us to access. We will monitor this issue.

Additionally, we need your help to confirm these questions:

1. Is the packet loss specific to a particular interface/VLAN, or does this happen on all interfaces?
2. "Seeing some random packet loss 3-12 hours at a time"⇒ Is the packet loss situation that when testing the destination IP with ICMP, it shows that packets are entering the LAN but not leaving the WAN? Do they disappear between the two firewall interfaces?
3. "Seeing some random packet loss 3-12 hours at a time" ⇒ When this happens, will it automatically recover without any action, or is manual intervention required?

I will send you a private message so you can share the Teamviewer access code and password in private.

PeterUK

ok Melen

I believe it happens on all interfaces its like the ingress buffer fill up and the FLEX H in not pulling packets out the ingress buffers to cause packet loss?

Yes it automatically recover without any action

I test PC with a running Ping to 1.0.0.1 and 192.168.168.1

PeterUK

So as you will not be checking till Monday I think I found something

so I was seeing packet loss over a bridge with my Main PC ( not test PC) the two 10Gb Ethernet I then connected the test PC to direct to P12 and this have SNAT out SFP P14 which connects to a XGS1250-12 then to the rest of the network to internet the XGS1250-12 is connected by smart plug to turn off when the internet gone down then up to trigger FLEX 700H to DHCP. And I was seeing more packet loss happen for the test PC Ping to 9.9.9.9 (I change this to 1.0.0.1 seem more stable) and 192.168.168.1 so I unplug the bridge ports and it was still doing it.

Sometime there will be packet loss to 1.0.0.1 and not 192.168.168.1 which just happens normally the problem is when both happen.

so to rule out problems with my test PC I have connect to Zywall 110 to test it can ping fine and stable before back to FLEX 700H for you to check Monday. update test PC is fine on Zywall 110

But could the problem be caused by the SPF for the Ethernets? So one test after you checked could be to unplug SFP and test?