SFT1200 VPN DNS issue on the v4.7.2

Lets call it 7.4.2.1
Opened the box again, and installed it.
Just that little convenient test stream: https://www.waveform.com/tools/bufferbloat

A very quick test learns ...

  • TX power is OK now (-30dBm received on short distance). TXPower setting in GUI is responsive.
  • 40MHz bandwidth is correct (but his might come from my earlier LUCI settings)
  • no scan/connection to DFS channels
  • AMPDU still breaks. This is not a wifi 802.11 n or ac device. It cannot handle that mode, as those wifi modes have up to 64 MPDU in one A-MPDU transmission.

Log claims MSDU not MPDU (typo ?)

Tue Mar 11 19:57:03 2025 kern.warn kernel: [ 585.975126] lmac[1] Error, msdu index reach maximum limit, 31
Tue Mar 11 19:57:03 2025 kern.warn kernel: [ 585.980967] lmac[1] Error, buffer is not uploaded to host buffer completely

Back in the box, this is not a good travel router for now, with that wifi driver. (only 31 MPDU are accepted, hopefully there is at least retransmit of the rest of the A-MPDU?)

Maybe I'll do some more tests, like with previous versions (eg country code), and see how bad the performance drops while using repeater. It may be sub-optimal but repeating the missed part of an A-MPDU might eventually give enough performance for a travelrouter. Have to find the config file with the "ampdu_max_cnt" configuration in this version. SFT1200 2.4 GHz Repeater Disconnects - #61 by bpwl1

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