Ping loss is observed while performing iw scan in mesh network

Chipset : MT7620A
Mode: Mesh mode
Description: Mesh network is created by using two devices having same MT7620A chipset on 5Ghz interface.Ping loss is observed while pinging between the mesh nodes and in parallel performing "iw dev wlan0 scan" on any of the node.

Doesn't scanning involve hopping through all the channels, and thus losing connectivity?


Ya the channel will be switching, But the issue is not observed when I perform the same test between Third Party AP and this MT7620A device in STA Mode. Issue is observed only between Same chipset devices.

you kinda lost me there.

scanning involves channel hoping and therefore packet loss -period-

I mean if I perform the same test between MT7620 device and any other Home AP with different chipset there is no any issue

Issue is observed only when I connect MT7620 devices each other through mesh mode.

This is quite unusual... could you please describe both scenarios completely?

Scenario 1-While I am performing Ping between two mesh nodes having MT7620 chipset , At same time if I perform wifi scan there is ping loss(About 3 icmp packets) observed while scanning. Both Rx and Tx are blocked during scanning.

Scenario 2-If I connect one among these devices to Any Home AP(Ref: linksys EA6100) there is a bit ping delay if I perform wifi scan in parallel. But not A single packet is lost.

Perhaps the AP is buffering the packets while one node is scanning, while in the mesh network packets are simply dropped.

Can do the same in mesh network also??

The radio is down for communication. What would be the practical benefit of holding the ICMP packets whose purpose is to determine if the device answers at the moment?

You loose 3 packets...

It seems that the cause is how the MT7620 scans.

Have you reversed the scenario of client/AP with the EA6100 (e.g. make the Linksys the client during testing instead)?

Ya reverse way also I tried with Linksys EA6100 as client, No issue is observed

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