Packet drops happening again

Just got the news about the 5/8 rolling release fixing a bunch of issues, but it did not fix this TX drop issue. Still occuring on 1.3-rolling-202005082150

3.75% packetloss of packets under 214 bytes thru vyos router on xen hypervisor

Just tested on 1.2.5 and cannot reproduce

I can reproduce with the steps mentioned by sonicbx on xcp-ng 8.x and recent rolling versions. I am happy to provide access to some VMs in order to help solving the issue.

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Glad to hear it’s not just me!

I created my first phabricator task!

https://phabricator.vyos.net/T2505

Hi @sonicbx, Can you check this behavior behind on Debian or similar distributives on this hypervisor?

I did try making a Debian 10 VM and enabled up forwarding and it doesn’t have any problem.

It´s happens in HVM mode or in PV or both?

Both HVM and PV …

Worth noting that as HVM it still uses PV NIC drivers because they’re preinstalled.

I don’t know how to force it to use HVM drivers.

I confirm TX-DROP on rolling.
R1 and R3 - LTS
R2 - rolling

R1_eth1 == eth1_R2_eth2 == eth1_R3

Ping:
R1= R2_eth1 without problems
R1 = R2_eth2 without problems
R1 = R3 - 7% loss

I’ll try to figure it out.

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Thank you for trying to resolve this!

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Presumably, this problem can be solved by this patch. ref. [net-next] xen-netfront: avoid packet loss when ethernet header crosses page boundary - Patchwork
Need to check it out.

I would be happy to do some tests with this patch. Is there any easy way to cross-compile the vyos kernel?

Hi,
Did anyone find a working fix? Am currently running 1.4-rolling-202101300218 on XCP-NG with around 1-2% packets dropped on TX.

Iface      MTU    RX-OK RX-ERR RX-DRP RX-OVR    TX-OK TX-ERR TX-DRP TX-OVR Flg
eth0      1500 55393733      0     71 0      93398166      0 1094371      0 BMRU
eth1      1500 94974007      0      0 0      98273116      0 885979      0 BMRU
eth2      1500 22236780      0      0 0      60714591      0 212657      0 BMRU
eth3      1500        0      0      0 0             7      0      0      0 BMRU
eth4      1500 17282995      0      0 0      43214192      0 262450      0 BMRU
eth5      1500        3      0      0 0           220      0      0      0 BMRU
eth6      1500  6829409      0      0 0       4785681      0 184062      0 BMRU