RT-AX88U : Tired of random PPPOe disconnects

[sanke1]

I am sick of PPPOe disconnects on my ASUS RT-AX88Us. FTTH ONU is in bridge mode and RT-AX88U does PPPOe dialing.

While people here will be smart enough to point out... duh it's your ISP.... but I replaced this router with $20 TP-Link and that thing held the PPPOe connection for 1 month straight without dropping a single time.
I am using the latest firmware 3.0.0.4.386.42095 at the time of writing.
I have even tried merlin as well. I replaced the CAT6 cable between ONU and Asus to rule out cable issues. I have reset the router countless times. I disabled IPV6 to see if that solves the issue but no.

Following is the same error everytime.

Apr 28 16:41:14 pppd[1775]: Serial link appears to be disconnected.
Apr 28 16:41:14 odhcp6c[26224]: Failed to send DHCPV6 message to ff02::1:2 (Network is unreachable)
Apr 28 16:41:14 rc_service: dhcp6c 29891:notify_rc restart_ddns
Apr 28 16:41:14 start_ddns: update WWW.NO-IP.COM noip, wan_unit 0
Apr 28 16:41:14 ddns update: ez-ipupdate: starting...
Apr 28 16:41:14 ddns update: could not resolve ip address for ppp0.
Apr 28 16:41:19 WAN Connection: Fail to connect with some issues.
Apr 28 16:41:20 pppd[1775]: Connection terminated.
Apr 28 16:41:20 pppd[1775]: Modem hangup
Apr 28 16:41:30 pppd[1775]: Connected to 00:23:3e:86:8b:95 via interface eth0
Apr 28 16:41:30 pppd[1775]: Connect: ppp0 <--> eth0
Apr 28 16:41:30 pppd[1775]: PAP authentication succeeded
Apr 28 16:41:30 pppd[1775]: peer from calling number 00:23:3E:86:8B:95 authorized
Apr 28 16:41:30 pppd[1775]: local  LL address fe80::f9eb:08db:9c43:fa64
Apr 28 16:41:30 pppd[1775]: remote LL address fe80::0223:3eff:fe86:8a50
Apr 28 16:41:30 pppd[1775]: local  IP address 182.56.999.999 (IP Address changed for security)
Apr 28 16:41:30 pppd[1775]: remote IP address 182.56.0.1
Apr 28 16:41:30 rc_service: ipv6-up 29959:notify_rc start_dhcp6c
Apr 28 16:41:30 modprobe: module ip6t_REJECT not found in modules.dep
Apr 28 16:41:30 modprobe: module ip6t_ROUTE not found in modules.dep
Apr 28 16:41:30 modprobe: module ip6t_LOG not found in modules.dep
Apr 28 16:41:31 wan: finish adding multi routes
Apr 28 16:41:31 miniupnpd[26278]: shutting down MiniUPnPd
Apr 28 16:41:31 miniupnpd: it is advised to use network interface name instead of 192.168.1.1/255.255.255.0
Apr 28 16:41:31 miniupnpd[30018]: HTTP listening on port 40382
Apr 28 16:41:31 miniupnpd[30018]: Listening for NAT-PMP/PCP traffic on port 5351
Apr 28 16:41:31 start_ddns: update WWW.NO-IP.COM noip, wan_unit 0
Apr 28 16:41:31 ddns update: ez-ipupdate: starting...
Apr 28 16:41:31 ddns update: connected to dynupdate.no-ip.com (158.247.7.204) on port 443.
Apr 28 16:41:32 ddns update: request successful
Apr 28 16:41:32 ddns update: asusddns_update: 0
Apr 28 16:41:32 ddns: ddns update ok
Apr 28 16:41:32 ddns update: exit_main
Apr 28 16:41:39 WAN Connection: WAN was restored.

Frequency of disconnects is random. Sometimes disconnects in 30 mins to sometimes 4 hrs. To be honest... I am sick of this expensive router.

@ASUSWRT_2020

 

[Hawk]

Not sure what to say, the only thing I can think of is probably the implementation of PPPOE, I have the same router and using FTTH with PPPoE setup, no disconnects on my side. Have you tried different firmware, not merlin, and see if it goes away. Also, try to do a factory reset.

 

[sanke1]

Not sure what to say, the only thing I can think of is probably the implementation of PPPOE, I have the same router and using FTTH with PPPoE setup, no disconnects on my side. Have you tried different firmware, not merlin, and see if it goes away. Also, try to do a factory reset.

Same problem with older firmwares. I have factory reset multiple times till now. I managed to return the earlier one and get a new one with A1.1 revision. Still the same issue with new piece as well.

 

[sputnikk]

Same problem on RT-AX56U. At least yours attempts to reconnect. I have to toggle WAN to bring it back.

 

[John8oy]

I’m getting this exact same issue on a RT-AX88U
This router was fine on Virgin media Cable. As soon as I switched providers to Vodafone Gigafast City Fibre connect using PPPOe I get regular WAN disconnections. The separate fibre modem remains solid with a Constance service light. To restore the connection I have to reboot the ASUS router and this resolves for a while. I’m also running an AIMesh node on same network connected by wire it’s a TUF-AX5400. I’ve seen something suggesting the TUF doesn’t support AIMesh over wire but seems to work, unsure if my disconnection issues could relate to this but I’d say unlikely.

 

[John8oy]

Worth noting. I’m using the latest Merlin firmware 386.4