[Upgrade Roadmap] OpenWrt 19.07.3 -> newest release for TP-Link Archer v5 EU

Hello guys,

I had my TP-Link Archer C7 AC1750 v5 (EU) laying around for some time now and I would like to update while keeping most of the settings.

I have these custom settings:
Custom firewall rules
Disabled IPv6, in the new firmware I would like to enable it since I have native dual stack now.
Some settings are changed, can't remember which ones specifically.

My hardware and software is:
TP-Link Archer C7 v5 (EU)
OpenWrt 19.07.3 r11063-85e04e9f46 / LuCI openwrt-19.07 branch git-20.136.49537-fb2f363

My questions would be:

  1. Can I just use the sysupgrade update safely to update and keep all my settings? Or do I need to take a specific path to achieve this?
  2. Can I directly update from this version to 21.02.1?
  3. Is there any possible trouble with the EU version?
  4. Is there still a hard limit of WAN->LAN bandwidth over Ethernet for the C7 v5 EU? My internet is apparently faster than 300Mbit and I would like to make full use of it. Yes, I've read the wiki back then and now.


  1. no, you should reset your settings going to 21.02, sysupgrade is however the right way to go.
  2. yes
  3. haven't seen any post about it.
  4. there's always a hard limit

Thank you for your answers.
With the first point you're meaning that I have to manually reset my settings before going for the upgrade?

When you upgrade via LuCI web interface, the system will give you the option to keep settings. Make sure that the box is unchecked (this will reset the router to the default settings during the upgrade process).

1 Like

The Archer c7 is not fast enough for this WAN speed (probably up to ~180-220 MBit/s, depending on your tolerance for lags; around (below-) 100 MBit/s with SQM enabled), you'd need to enabled software flow-offloading to extend that further (which comes with its own quirks).

I used dslreports.com to measure my Bufferbloat and I got less than 5ms avg, is there any use of enabling SQM?
I use the connection for gaming sometimes, so lower latency might be advantageous.

Does enabling software flow-offloading have any security disadvantages?

P.S. I'm usually the only one hoarding the connection, so there's no use for SQM, right? I tried it out and I got A+ score but 33Mbit download speed.

There's only one way to find out…
…test it.

No, not every ISP connection needs SQM - nor does every usage profile profit from it. Especially towards the lower throughput spectrum the loss of total throughput with SQM might be worse than reasonable lags.
The situation for avid online gamers is different again, I won't even try to qualify these usage patterns, as I've never been a gamer to begin with.

I tried it out, the latency dropped down by quite a bit, but the download speed became 33Mbit max. Enabling/disabling it is too much trouble imho.

Any clue whether software flow-offloading has any security disadvantages btw? I tried googling but found nothing about it... Does it bypass my Firewall rules somehow?

SQM needs a considerably fast router, to cope with modern WAN speeds and still remain effective and on top of the connection. The archer c7 should still be faster than 33 MBit/s though (but it won't pass the 3 figure range either).

In terms of security exposure, SQM wouldn't be my first concern.