TP-Link Archer C6U - impressions: test / configuration / stability / functionality feedback

Hi,

I like to share my observations and experiences with this router TP-Link Archer C6U v1 EU after a few weeks of testing and trying to get certain functionality to work. What I did to get to this point and hopefully be useful so other don't waste so much time figuring this out. I will try an unbiased balanced report, whenever I mention something is not working well is just stating facts from experience, it is not meant as criticism but meant to help developers and users to achieve success and improvements. I will also report on the good things I've noticed next to the bad things, will refer to issues and problems that are also reported here in the forums.

In general this little router has good potential, is very cheap at the moment and was acquired specifically by me in order to experiment and test mesh, wds , guest networking , interconnect stability with more than 1 unit. The only 'downside' for this router is the small flash size (16Mb) which limits the packages you can install. But fortunately , the USB port functions fine, so the option to add an external flash drive and overlay it would work around this. I do not need Samba but after all the packages I really needed/wanted I could not add this one. Samba is quite a huge packages compared to the rest though. I've had iscsi (server), SQM , openvpn working properly. I chosen to experiment with this router specifically to have a platform that uses Mediatek hardware/wifi chipset.

What I did not test/analysed is throughput performance. From using it daily it seems to do OK, but given the specs of this router it's needless to state that this will not be up to par with more beefy routers, but nevertheless seems to be handling itself quite well.

Setup conditions:

Three units, all named caretaker 1 to 3

  • caretaker1 - WAN gateway - WDS gateway - floor 0 - TV connected by wire
  • caretaker2 - WDS client station - floor 1 ( concrete floor )
  • caretaker3 - WDS client station - floor 0 ( 12 meters from caretaker1 )

Client stations

  • Ubuntu 20.04 - Asus Zenbook - very recent hardware
  • Ubuntu 20.04 - Asus Zenbook - old machine
  • Windows 10 - Asus Vivobook - a few years old
  • Windows 10 - Asus ROG - also aged few years
  • Oneplus 6T
  • Samsung S10 (*2)
  • Samsung Tablets ( *3)
  • Naim / Samsung TV (cabled connection, less relevant )

Placement: 3 floor apartment, reinforced concrete walls and floors. vertical coverage is the challenge

Setup/ configuration

General observations - stable release

Installing / configuring the routers is trivial and pretty much vanilla OpenWrt installation, Some specific things to know when doing this from the OEM firmware I have documented on the device page. Nothing really earth shattering there. During this process I've also create a device page to record my findings. I would like to invite users to contribute to completing this.

Stability however was not ok. specifically the WIFI part. I could watch hours of netflix through this router without any issues at all, but the WDS connections between stations and also the wifi clients were lost regularly, to the point that it is unworkable.

Setting up a mesh network seems to work initially but after some time the mesh setup gets broken and a kernel WARN is thrown. This doesn't seem to happen when using WDS to interconnect the routers.

But with the stable release, WDS had issues that caretaker2 and caretaker3 often stopped responding and the association of those client stations was lost to caretaker1.

IRQ issues : Users have reported and I could confirm this with 1 router that this was happening. The IRQ problem comes in 2 shapes: You have a ksoftirqd/3 process/thread that is eating up about 25% of the CPU load , and there seems to be an excessive IRQ error counter. But for me it didn't happen on all 3 at the same time.
long lived ssh sessions to three routers become very unresponsive, often just blocking only to recover minutes later, the console 'felt' quite slugish, experiencing latency and unresponsiveness

A forum search will show that users in the past (before the current stable release) have been reporting a number of issues that I will still have to test more . Specifically performance , vlan would be on my list

As a conclusion, I would expect everybody using the stable release to experience these issues and probably be disappointed . But now the good news.

General observations - snapshot release

  • OpenWrt SNAPSHOT, r18942-cbfce92367

I decided to install the same snapshot on all three, reconstructed the routers from the package list from stable release. The only package that refused to install was wpad-openssl due to a dependency to hostapd , however making it ignore and force the installation made the WiFi radio work... and work good! Keeping in mind this is still a snapshot.

Although the snapshot hasn't been running quite as long as the time I spent with the stable release to discover problems. It made a huge difference already. Monitoring all three routers for issues overnight showed the disassociation only happened once on caretaker3, it recovered in the same second and was not the farthest router. caretaker2 didn't have any loss of the WDS sid at all. This is a huge contrast with the stable release. all the WIFI sid's work a lot better, the guest network, the WDS network and a third network all keep working fine.

The ksoftirqd load problem seems gone. I do not see it anymore, usually before this change after a bit of uptime, I see it in 1 router atleast. So far, nothing. The IRQ error counters do seem to rise, it rises the most on the gateway (caretaker1), almost none on caretaker2 and caretaker3 has a few 100 (but caretaker2 has been rebooted due to placing it on another floor to test coverage)

uptime 1 and 3 : 13hrs
uptime 2 : 2 hrs at the time I wrote this

root@caretaker1:~# cat /proc/interrupts 
           CPU0       CPU1       CPU2       CPU3       
  7:          0          0          0          0      MIPS   7  timer
  8:    4597167    4597149    4597142    4597134  MIPS GIC Local   1  timer
  9:    5975055          0          0          0  MIPS GIC  63  IPI call
 10:          0   16317548          0          0  MIPS GIC  64  IPI call
 11:          0          0   14134460          0  MIPS GIC  65  IPI call
 12:          0          0          0   11712736  MIPS GIC  66  IPI call
 13:     110962          0          0          0  MIPS GIC  67  IPI resched
 14:          0     443040          0          0  MIPS GIC  68  IPI resched
 15:          0          0    3499400          0  MIPS GIC  69  IPI resched
 16:          0          0          0    1365750  MIPS GIC  70  IPI resched
 17:          0          0          0          0  MIPS GIC  19  1e000600.gpio-bank0, 1e000600.gpio-bank1, 1e000600.gpio-bank2
 19:         12          0          0          0  MIPS GIC  33  ttyS0
 20:          0          0          0          0  MIPS GIC  29  xhci-hcd:usb1
 21:   11140976          0          0          0  MIPS GIC  10  1e100000.ethernet
 22:         22          0          0          0  MIPS GIC  11  mt7603e
 23:         18          0          0    5298546  MIPS GIC  31  mt7615e
 25:         78          0          0          0  MIPS GIC  30  mt7530
 26:          5          0          0          0    mt7530   0  mt7530-0:00
 27:         21          0          0          0    mt7530   1  mt7530-0:01
 28:         43          0          0          0    mt7530   2  mt7530-0:02
 29:          9          0          0          0    mt7530   3  mt7530-0:03
 30:          0          0          0          0    mt7530   4  mt7530-0:04
 31:          0          0          0          0  1e000600.gpio   8  keys
 32:          0          0          0          0  1e000600.gpio  10  keys
ERR:       1811

root@caretaker2:~# cat /proc/interrupts 
           CPU0       CPU1       CPU2       CPU3       
  7:          0          0          0          0      MIPS   7  timer
  8:     525806     525788     525780     525773  MIPS GIC Local   1  timer
  9:     749269          0          0          0  MIPS GIC  63  IPI call
 10:          0    1172857          0          0  MIPS GIC  64  IPI call
 11:          0          0    1227527          0  MIPS GIC  65  IPI call
 12:          0          0          0     773102  MIPS GIC  66  IPI call
 13:      95500          0          0          0  MIPS GIC  67  IPI resched
 14:          0      66629          0          0  MIPS GIC  68  IPI resched
 15:          0          0     161719          0  MIPS GIC  69  IPI resched
 16:          0          0          0     101853  MIPS GIC  70  IPI resched
 17:          0          0          0          0  MIPS GIC  19  1e000600.gpio-bank0, 1e000600.gpio-bank1, 1e000600.gpio-bank2
 19:         12          0          0          0  MIPS GIC  33  ttyS0
 20:          0          0          0          0  MIPS GIC  29  xhci-hcd:usb1
 21:         16          0          0          0  MIPS GIC  10  1e100000.ethernet
 22:         23          0          0          0  MIPS GIC  11  mt7603e
 23:         18          0          0     318070  MIPS GIC  31  mt7615e
 25:          0          0          0          0  MIPS GIC  30  mt7530
 26:          0          0          0          0    mt7530   0  mt7530-0:00
 27:          0          0          0          0    mt7530   1  mt7530-0:01
 28:          0          0          0          0    mt7530   2  mt7530-0:02
 29:          0          0          0          0    mt7530   3  mt7530-0:03
 30:          0          0          0          0    mt7530   4  mt7530-0:04
 31:          0          0          0          0  1e000600.gpio   8  keys
 32:          0          0          0          0  1e000600.gpio  10  keys
ERR:          5

root@caretaker3:~# cat /proc/interrupts 
           CPU0       CPU1       CPU2       CPU3       
  7:          0          0          0          0      MIPS   7  timer
  8:    4368682    4368666    4368658    4368650  MIPS GIC Local   1  timer
  9:    6773173          0          0          0  MIPS GIC  63  IPI call
 10:          0   10724448          0          0  MIPS GIC  64  IPI call
 11:          0          0   10729279          0  MIPS GIC  65  IPI call
 12:          0          0          0    6599757  MIPS GIC  66  IPI call
 13:    1044898          0          0          0  MIPS GIC  67  IPI resched
 14:          0     638509          0          0  MIPS GIC  68  IPI resched
 15:          0          0    1788548          0  MIPS GIC  69  IPI resched
 16:          0          0          0     919647  MIPS GIC  70  IPI resched
 17:          0          0          0          0  MIPS GIC  19  1e000600.gpio-bank0, 1e000600.gpio-bank1, 1e000600.gpio-bank2
 19:         12          0          0          0  MIPS GIC  33  ttyS0
 20:          0          0          0          0  MIPS GIC  29  xhci-hcd:usb1
 21:     249297          0          0          0  MIPS GIC  10  1e100000.ethernet
 22:         21          0          0          0  MIPS GIC  11  mt7603e
 23:         16          0          0    3448283  MIPS GIC  31  mt7615e
 25:          5          0          0          0  MIPS GIC  30  mt7530
 26:          0          0          0          0    mt7530   0  mt7530-0:00
 27:          0          0          0          0    mt7530   1  mt7530-0:01
 28:          0          0          0          0    mt7530   2  mt7530-0:02
 29:          5          0          0          0    mt7530   3  mt7530-0:03
 30:          0          0          0          0    mt7530   4  mt7530-0:04
 31:          0          0          0          0  1e000600.gpio   8  keys
 32:          0          0          0          0  1e000600.gpio  10  keys
ERR:        212

on the point of ssh, all the shells I keep open on the 'old' zenbook (logread -f ) are left open, their response is perfect and I don't experience anymore what I've experienced using the stable release at all.

None of the clients (Oneplus6t in particular as it's my main phone) lost connectivity while walking around the house playing some online poker :slight_smile: . Which seems to be about the best test I could figure out since this application seems very sensitive to even the smallest hiccup.

Coverage is also a lot better, a room where when I placed one of the routers and where it didn't work before, now associates fine where before I could not get it to connect to the WDS gateway.

My preliminary conclusion would be at the moment that the snapshot of that day works a lot better, it's remarkably more stable and leaves the impression that a lot of the issues users reported in the past have been taken care of by the development efforts so far. Pretty awesome and much appreciated.

general - non firmware version related issues

  • SQM seems to not auto-start at boot or restart of the wifi/interface. After some digging , the solution to this issue can be resolved by following instructions here SQM-scripts . I'm not 100% but that seems to be the origin of those scripts and the make openwrt option is tailored to fixing any issues with auto-starting this functionality. It's my educated guess that this issue is not really related to the router this subject covers.

As the focus of my research was to try and create a router setup using 3 units to serve a small office (chiropractor) in a private house, where a WiFi network was needed for the guests that are waiting under SQM control, a separated network for the office computers, that was isolated from the WDS network so the private computers where also isolated from the 'main/management' network , it seems that this is starting to become a valid solution. Stability was the main focus, and I will still need to test the following again with the snapshot release : mesh , to see if the kernel warn is still happening, VLAN's seem to also have some issues reported so I'll throw that in as well to confirm/deny. Although the location where I started to design this solution for has cables running to most places, which would be much more superior to running WDS, I wanted to have WDS tested in case a cable wasn't available depending on the placement. It's my brothers house so I wanted this to be a better solution that he currently has using 4 different brands of devices, a repeater mess and a 5GHz network he only activates when he wants to make a copy to his NAS because the 5GHz network he has now is not good.

I only tested 5GHz due to this, but in my experience, 2.4GHz in OpenWrt hardly has issues in any of the routers I own/tested running openwrt. (WRT1200AC *2 , EA8300 , MR8300 )

I hope this helps other users find a working setup and also I hope this is somewhat useful for developers to both signal that they are doing good work and to help focus on the last few bits that could use some love in order to support this little gem of a router.

I like to express my sincere gratitude for all those efforts and I will try and send updates on further tests I perform keeping the feedback loop alive. I would also like to offer my help in testing these out, given the unique opportunity of owning 3 of these routers.

Glenn

4 Likes

Question: did you use the MT7613 radio for your WDS? I seem to remember the driver had WDS disabled at some point in more recent versions, specifically for the MT7613.

1 Like

Hi ,

I do indeed.

This is something that confused me when unpacking/installing. The card 5Ghz seems to be a MediaTek MT7613BE 802.11nac as reported in Openwrt. The drivers that are loaded are mt615e

root@caretaker2:~# lsmod | grep mt
cfg80211              299132  5 mt7615_common,mt7603e,mt76_connac_lib,mt76,mac80211
hwmon                   8742  1 mt7615_common
mac80211              555208  5 mt7615e,mt7615_common,mt7603e,mt76_connac_lib,mt76
mt76                   48100  4 mt7615e,mt7615_common,mt7603e,mt76_connac_lib
mt76_connac_lib        26833  2 mt7615e,mt7615_common
mt7603e                40284  0 
mt7615_common          68966  1 mt7615e
mt7615e                11469  0 
usbcore               154936  5 ledtrig_usbport,xhci_plat_hcd,xhci_pci,xhci_mtk,xhci_hcd
xhci_hcd              120157  3 xhci_plat_hcd,xhci_pci,xhci_mtk
xhci_mtk                4978  0 

WDS setup 'worked' on both stable and snapshot, but on the snapshot it's stable.

And so far, it's doing great tbh. I've typed all this over 'this driver' :wink:

Any more questions/ test request, please shoot. I would love to get these routers do great, I kinda like them, for a 35 euro router... they are awesome.

Thanks for clarifying. Well, MT7613BE is a sibling of the MT7615. Hence why the driver is the same. But the driver does not support DFS (yet?) e.g. for MT7613BE. Even with the OEM firmware I believe DFS is not supported.

There is one problem I forgot to mention.

In the stable release, I tested using a channel where DFS is required in my region. Any channel upwards from 52 needs DFS.

Tue Feb 22 14:02:11 2022 daemon.notice hostapd: wlan1: interface state UNINITIALIZED->COUNTRY_UPDATE
Tue Feb 22 14:02:11 2022 daemon.notice hostapd: wlan1: interface state COUNTRY_UPDATE->DFS
Tue Feb 22 14:02:11 2022 daemon.notice hostapd: wlan1: DFS-CAC-START freq=5260 chan=52 sec_chan=1, width=0, seg0=54, seg1=0, cac_time=60s
Tue Feb 22 14:02:11 2022 daemon.err hostapd: DFS start_dfs_cac() failed, -1
Tue Feb 22 14:02:11 2022 daemon.err hostapd: Interface initialization failed
Tue Feb 22 14:02:11 2022 daemon.notice hostapd: wlan1: interface state DFS->DISABLED
Tue Feb 22 14:02:11 2022 daemon.notice hostapd: wlan1: AP-DISABLED
Tue Feb 22 14:02:11 2022 daemon.err hostapd: wlan1: Unable to setup interface.

This doesn't seem to be how it should work imho, for BE it should listen for 60 seconds to spot radars but it immediately bails out with : DFS start_dfs_cac() failed, -1

I assume this to be an upstream driver issue, channel 52 is a valid option for regulatory domain BE. When I change this to IN (india) where the DFS requirement is not need, the channel works fine.

I forgot to mention that in my initial post. this one also made me go through the driver code for a few hours. I just reproduced this in the snapshot version, but I noticed this first with the stable release, so it's still the case now.

You beat me to it, I can confirm, DFS cac is not working which limits to either take the chance to change the region, or to use a lower channel.

Nope, check this topic for the nitty gritty:

1 Like

Could you share how you got the USB port to work? I just got an Archer C6U and flashed OpenWrt 21.02.2; and I'm unable to get any devices to be recognized. I followed the Quickstart in the wiki. Thanks!

opkg update && opkg install kmod-usb-core kmod-usb-xhci-mtk kmod-usb3 kmod-usb-storage kmod-usb-ohci kmod-usb2 kmod-usb3 kmod-usb-storage-uas usbutils block-mount e2fsprogs kmod-fs-ext4 libblkid kmod-fs-f2fs f2fs-tools

Insert USB drive:

dmesg:

[ 7217.886674] usb 1-2: new high-speed USB device number 2 using xhci-mtk
[ 7250.175250] usb 1-2: USB disconnect, device number 2
[ 7285.068505] kmodloader: loading kernel modules from /etc/modules.d/*
[ 7285.081468] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
[ 7285.090290] ehci-fsl: Freescale EHCI Host controller driver
[ 7285.098731] ehci-platform: EHCI generic platform driver
[ 7285.109972] ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver
[ 7285.118456] ohci-platform: OHCI generic platform driver
[ 7285.135538] usbcore: registered new interface driver usb-storage
[ 7285.145448] usbcore: registered new interface driver uas
[ 7285.151692] kmodloader: done loading kernel modules from /etc/modules.d/*
[ 7285.239811] kmodloader: loading kernel modules from /etc/modules.d/*
[ 7285.255968] kmodloader: done loading kernel modules from /etc/modules.d/*
[ 7285.343542] kmodloader: loading kernel modules from /etc/modules.d/*
[ 7285.359494] kmodloader: done loading kernel modules from /etc/modules.d/*
[ 7285.447269] kmodloader: loading kernel modules from /etc/modules.d/*
[ 7285.463230] kmodloader: done loading kernel modules from /etc/modules.d/*
[ 7285.551003] kmodloader: loading kernel modules from /etc/modules.d/*
[ 7285.567151] kmodloader: done loading kernel modules from /etc/modules.d/*
[ 7293.215619] usb 1-2: new high-speed USB device number 3 using xhci-mtk
[ 7293.416634] scsi host0: uas
[ 7294.284999] scsi 0:0:0:0: Direct-Access     ROG      ESD-S1C          0    PQ: 0 ANSI: 6
[ 7294.728704] sd 0:0:0:0: [sda] 1953525168 512-byte logical blocks: (1.00 TB/932 GiB)
[ 7294.736667] sd 0:0:0:0: [sda] Write Protect is off
[ 7294.741454] sd 0:0:0:0: [sda] Mode Sense: 43 00 00 00
[ 7294.747178] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[ 7294.761152]  sda: sda1
[ 7294.767366] sd 0:0:0:0: [sda] Attached SCSI disk

root@caretaker3:~# lsusb 
Bus 001 Device 003: ID 0b05:1932 ASUS ROG STRIX Arion
Bus 002 Device 001: ID 1d6b:0003 Linux 5.10.100 xhci-hcd xHCI Host Controller
Bus 001 Device 001: ID 1d6b:0002 Linux 5.10.100 xhci-hcd xHCI Host Controller
root@caretaker3:~# lsusb -t
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci-mtk/1p, 5000M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci-mtk/2p, 480M
    |__ Port 2: Dev 3, If 0, Class=, Driver=uas, 480M

They are probably not all needed, depending on the type of usb storage you insert, but this just worked for me (snapshot kernel)

This USB drive is a Asus ROG Strix Arion - M.2 NVMe SSD Enclosure

root@caretaker3:~# block detect 
config 'global'
	option	anon_swap	'0'
	option	anon_mount	'0'
	option	auto_swap	'1'
	option	auto_mount	'1'
	option	delay_root	'5'
	option	check_fs	'0'

config 'mount'
	option	target	'/mnt/sda1'
	option	uuid	'80061c90-4352-4084-aad6-7a1665a0b5ae'
	option	enabled	'0'

test:

mkdir /mnt/flash
mount -t ext4 /dev/sda1 /mnt/flash
[  235.310304] EXT4-fs (sda1): mounted filesystem with ordered data mode. Opts: (null)

I had a OOM error when mounting the same drive (I have 2, one with ext4 and 1 with f2fs) with f2fs filesystem , not with ext4 strangly enough. I didn't notice that until now testing this again I took the f2fs one first.

You might want to cherry pick the mentioned packages to preserve memory as 16MB flash is pushing it.

[  125.678907] netifd invoked oom-killer: gfp_mask=0x100cca(GFP_HIGHUSER_MOVABLE), order=0, oom_score_adj=0
[  125.688404] CPU: 1 PID: 1584 Comm: netifd Not tainted 5.10.100 #0
[  125.694472] Stack : 80a30000 8084a40c 00000000 80083400 808c0000 807b0270 00000000 00000000
[  125.702826]         82c85bd4 80a10000 8077e390 818167a8 8084ce87 00000001 82c85b78 448237ff
[  125.711174]         00000000 00000000 8077e390 82c85a18 ffffefff 00000000 ffffffea 00000000
[  125.719518]         82c85a24 00000189 80852858 ffffffff 80000000 00000001 00000000 80780000
[  125.727885]         808d3448 00000009 00001000 8084a40c 00000018 80403f20 00000004 80a10004
[  125.736232]         ...
[  125.738674] Call Trace:
[  125.741136] [<800080e0>] show_stack+0x30/0x100
[  125.745579] [<8037e9d8>] dump_stack+0x9c/0xcc
[  125.749940] [<80138640>] dump_header+0x58/0x1d4
[  125.754451] [<80138ea0>] oom_kill_process+0x1fc/0x204
[  125.759479] [<8013989c>] out_of_memory+0x210/0x394
[  125.764255] [<80182324>] __alloc_pages_nodemask+0x6fc/0xe88
[  125.769809] [<8013501c>] pagecache_get_page+0x148/0x440
[  125.775013] [<80136ef0>] filemap_fault+0x7f0/0x9cc
[  125.779806] [<801657f4>] __do_fault+0x40/0x120
[  125.784231] [<8016b04c>] handle_mm_fault+0x9ac/0xe38
[  125.789185] [<800189c4>] do_page_fault+0x104/0x4bc
[  125.793981] [<8001dfe8>] tlb_do_page_fault_0+0x118/0x120
[  125.799274] 
[  125.801014] Mem-Info:
[  125.803308] active_anon:27 inactive_anon:567 isolated_anon:0
[  125.803308]  active_file:0 inactive_file:2 isolated_file:0
[  125.803308]  unevictable:0 dirty:0 writeback:0
[  125.803308]  slab_reclaimable:536 slab_unreclaimable:3236
[  125.803308]  mapped:10 shmem:16 pagetables:94 bounce:0
[  125.803308]  free:3986 free_pcp:0 free_cma:0
[  125.833542] Node 0 active_anon:108kB inactive_anon:2268kB active_file:0kB inactive_file:8kB unevictable:0kB isolated(anon):0kB isolated(file):0kB mapped:40kB dirty:0kB writeback:0kB shmem:64kB writeback_tmp:0kB kernel_stack:840kB all_unreclaimable? yes
[  125.855829] Normal free:15944kB min:16384kB low:20480kB high:24576kB reserved_highatomic:0KB active_anon:108kB inactive_anon:2240kB active_file:392kB inactive_file:404kB unevictable:0kB writepending:0kB present:131072kB managed:120224kB mlocked:0kB pagetables:376kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB
[  125.883634] lowmem_reserve[]: 0 0 0
[  125.887130] Normal: 429*4kB (UME) 280*8kB (UME) 190*16kB (UM) 79*32kB (UM) 24*64kB (UM) 15*128kB (M) 3*256kB (M) 5*512kB (UM) 0*1024kB 0*2048kB 0*4096kB = 16308kB
[  125.901700] 31 total pagecache pages
[  125.905261] 0 pages in swap cache
[  125.908557] Swap cache stats: add 0, delete 0, find 0/0
[  125.913780] Free swap  = 0kB
[  125.916646] Total swap = 0kB
[  125.919508] 32768 pages RAM
[  125.922316] 0 pages HighMem/MovableOnly
[  125.926131] 2712 pages reserved
[  125.929252] Tasks state (memory values in pages):
[  125.933959] [  pid  ]   uid  tgid total_vm      rss pgtables_bytes swapents oom_score_adj name
[  125.942614] [    721]    81   721      335       24    16384        0             0 ubusd
[  125.950921] [    727]     0   727      250        8    16384        0             0 askfirst
[  125.959334] [    766]     0   766      279       14    20480        0             0 urngd
[  125.967517] [   1224]   514  1224      338       16    16384        0             0 logd
[  125.975627] [   1288]     0  1288      534       38    20480        0             0 rpcd
[  125.983713] [   1422]     0  1422      303       12    20480        0             0 dropbear
[  125.992153] [   1521]     0  1521      666       14    20480        0             0 hostapd
[  126.000524] [   1522]     0  1522      666       14    16384        0             0 wpa_supplicant
[  126.009449] [   1549]   101  1549     1265       95    20480        0             0 wpa_supplicant
[  126.018396] [   1550]   101  1550     1246       70    20480        0             0 hostapd
[  126.026746] [   1584]     0  1584      453       39    16384        0             0 netifd
[  126.035016] [   1638]     0  1638      383       25    20480        0             0 odhcpd
[  126.043285] [   2205]     0  2205     1023       32    24576        0             0 uhttpd
[  126.051545] [   2913]     0  2913      337       18    20480        0         -1000 tgtd
[  126.059644] [   3064]     0  3064      666       26    20480        0             0 ntpd
[  126.067702] [   3067]   123  3067      328        8    16384        0             0 ntpd
[  126.075792] [   3921]     0  3921      308       15    20480        0             0 dropbear
[  126.084226] [   3922]     0  3922      331       14    20480        0             0 ash
[  126.092226] [   3934]     0  3934      328        8    16384        0             0 mount
1 Like

Hi, can you please write an easy guide on getting back to stock firmware as there are none & i don't want a brick. Any help would be much appreciated thanks.

The PR that merged support for TP-Link Archer C6U should help you. I have personally done it in order to revert to stock firmware once.: https://github.com/openwrt/openwrt/pull/3757

2 Likes

Update, since I forgot to do it sooner: the unit I initially received was confirmed to be faulty by the seller. The USB port was found to be dead. I soon received a replacement and I've been using extroot and smb without any problems. :)

Since you've done it. Can you please write down the steps. It would be really helpful

Be very careful during this process. It involves intentionally soft-bricking the router and then recovering from it. If something goes wrong, you will most likely be left with a bricked router.

What you're going to need:

  • the router itself
  • a PC with an ethernet port
  • the official firmware file
  • lots of courage

The procedure:

  1. ssh into your router. For example, ssh 192.168.1.1
  2. Execute the command (this will erase the firmware and force fallback onto the web recovery): mtd erase firmware
  3. Execute the command (this will attempt a reboot and fail because there is no longer a bootable kernel): reboot
  4. Follow method 1 on this page to install the official firmware: How to recover the router when it bricked | TP-Link

If everything went according to plan, your router will reboot into the official firmware.

1 Like

Thanks man you're a saviour.

@gplv2 Is still viable your opinion on this router with OpenWrt's current release 22.03.0 ?