This topic was the 1st result so posting here.
In the same boat with my RB1100AHx4 Dude using PPPoE.
Randomly, after a clean reboot or firmware upgrade, the PPPoE connection will loop forever.
The only fix is to reboot again or disable/enable the interface connecting to the GPON.
I have never experienced such problems with any prior routers in this location. Plenty Asus routers and X86 PFSense/IPFire machines.
I let it for 10 minutes last time it happened. No luck.
I had to disable ether1 and enable it back. Instant PPPoE connection.
[admin@RB1100AHx4] > /log print
mar/02 00:11:50 system,info router rebooted
mar/02 00:11:54 pppoe,ppp,info RDS: initializing...
mar/02 00:11:54 pppoe,ppp,info RDS: connecting...
mar/02 00:12:01 pppoe,ppp,info RDS: terminating...
mar/02 00:12:02 pppoe,ppp,info RDS: disconnected
mar/02 00:12:02 pppoe,ppp,info RDS: initializing...
mar/02 00:12:02 pppoe,ppp,info RDS: connecting...
mar/02 00:12:02 interface,info ether1 link up (speed 1G, full duplex)
mar/02 00:12:02 interface,info ether2 link up (speed 1G, full duplex)
mar/02 00:12:02 interface,info ether4 link up (speed 1G, full duplex)
mar/02 00:12:02 interface,info ether6 link up (speed 100M, full duplex)
mar/02 00:12:02 script,info Main connection DOWN. Enabling eth12
mar/02 00:12:02 system,info device changed
mar/02 00:12:10 interface,info ether12 link up (speed 1G, full duplex)
mar/02 00:12:11 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:12:11 pppoe,ppp,info RDS: disconnected
mar/02 00:12:11 pppoe,ppp,info RDS: initializing...
mar/02 00:12:11 pppoe,ppp,info RDS: connecting...
mar/02 00:12:11 system,info device changed
mar/02 00:12:11 script,info Main connection DOWN. Enabling eth12
mar/02 00:12:47 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:12:47 pppoe,ppp,info RDS: disconnected
mar/02 00:12:47 system,info device changed
mar/02 00:12:47 script,info Main connection DOWN. Enabling eth12
mar/02 00:12:47 pppoe,ppp,info RDS: initializing...
mar/02 00:12:47 pppoe,ppp,info RDS: connecting...
mar/02 00:12:57 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:12:57 pppoe,ppp,info RDS: disconnected
mar/02 00:12:57 system,info device changed
mar/02 00:12:57 script,info Main connection DOWN. Enabling eth12
mar/02 00:12:58 pppoe,ppp,info RDS: initializing...
mar/02 00:12:58 pppoe,ppp,info RDS: connecting...
mar/02 00:13:08 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:13:08 pppoe,ppp,info RDS: disconnected
mar/02 00:13:08 system,info device changed
mar/02 00:13:08 script,info Main connection DOWN. Enabling eth12
mar/02 00:13:10 pppoe,ppp,info RDS: initializing...
mar/02 00:13:10 pppoe,ppp,info RDS: connecting...
mar/02 00:13:20 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:13:20 pppoe,ppp,info RDS: disconnected
mar/02 00:13:20 system,info device changed
mar/02 00:13:20 script,info Main connection DOWN. Enabling eth12
mar/02 00:13:23 pppoe,ppp,info RDS: initializing...
mar/02 00:13:23 pppoe,ppp,info RDS: connecting...
mar/02 00:13:33 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:13:33 pppoe,ppp,info RDS: disconnected
mar/02 00:13:33 system,info device changed
mar/02 00:13:33 script,info Main connection DOWN. Enabling eth12
mar/02 00:13:40 pppoe,ppp,info RDS: initializing...
mar/02 00:13:40 pppoe,ppp,info RDS: connecting...
mar/02 00:13:50 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:13:50 pppoe,ppp,info RDS: disconnected
mar/02 00:13:50 system,info device changed
mar/02 00:13:50 script,info Main connection DOWN. Enabling eth12
mar/02 00:14:00 pppoe,ppp,info RDS: initializing...
mar/02 00:14:00 pppoe,ppp,info RDS: connecting...
mar/02 00:14:06 interface,info ether4 link down
mar/02 00:14:10 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:14:10 pppoe,ppp,info RDS: disconnected
mar/02 00:14:10 system,info device changed
mar/02 00:14:10 script,info Main connection DOWN. Enabling eth12
mar/02 00:14:20 pppoe,ppp,info RDS: initializing...
mar/02 00:14:20 pppoe,ppp,info RDS: connecting...
mar/02 00:14:26 interface,info ether4 link down
mar/02 00:14:30 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:14:30 pppoe,ppp,info RDS: disconnected
mar/02 00:14:30 system,info device changed
mar/02 00:14:30 script,info Main connection DOWN. Enabling eth12
mar/02 00:14:40 pppoe,ppp,info RDS: initializing...
mar/02 00:14:40 pppoe,ppp,info RDS: connecting...
mar/02 00:14:50 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:14:50 pppoe,ppp,info RDS: disconnected
mar/02 00:14:50 system,info device changed
mar/02 00:14:50 script,info Main connection DOWN. Enabling eth12
mar/02 00:15:00 pppoe,ppp,info RDS: initializing...
mar/02 00:15:00 pppoe,ppp,info RDS: connecting...
mar/02 00:15:10 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:15:10 pppoe,ppp,info RDS: disconnected
mar/02 00:15:10 system,info device changed
mar/02 00:15:10 script,info Main connection DOWN. Enabling eth12
mar/02 00:15:20 pppoe,ppp,info RDS: initializing...
mar/02 00:15:20 pppoe,ppp,info RDS: connecting...
mar/02 00:15:30 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:15:30 pppoe,ppp,info RDS: disconnected
mar/02 00:15:30 system,info device changed
mar/02 00:15:30 script,info Main connection DOWN. Enabling eth12
mar/02 00:15:40 pppoe,ppp,info RDS: initializing...
mar/02 00:15:40 pppoe,ppp,info RDS: connecting...
mar/02 00:15:50 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:15:50 pppoe,ppp,info RDS: disconnected
mar/02 00:15:50 script,info Main connection DOWN. Enabling eth12
mar/02 00:15:50 system,info device changed
mar/02 00:16:00 pppoe,ppp,info RDS: initializing...
mar/02 00:16:00 pppoe,ppp,info RDS: connecting...
mar/02 00:16:10 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:16:10 pppoe,ppp,info RDS: disconnected
mar/02 00:16:10 system,info device changed
mar/02 00:16:10 script,info Main connection DOWN. Enabling eth12
mar/02 00:16:20 pppoe,ppp,info RDS: initializing...
mar/02 00:16:20 pppoe,ppp,info RDS: connecting...
mar/02 00:16:30 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:16:30 pppoe,ppp,info RDS: disconnected
mar/02 00:16:30 system,info device changed
mar/02 00:16:30 script,info Main connection DOWN. Enabling eth12
mar/02 00:16:40 pppoe,ppp,info RDS: initializing...
mar/02 00:16:40 pppoe,ppp,info RDS: connecting...
mar/02 00:16:50 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:16:50 pppoe,ppp,info RDS: disconnected
mar/02 00:16:50 system,info device changed
mar/02 00:16:50 script,info Main connection DOWN. Enabling eth12
mar/02 00:17:00 pppoe,ppp,info RDS: initializing...
mar/02 00:17:00 pppoe,ppp,info RDS: connecting...
mar/02 00:17:10 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:17:10 pppoe,ppp,info RDS: disconnected
mar/02 00:17:10 system,info device changed
mar/02 00:17:10 script,info Main connection DOWN. Enabling eth12
mar/02 00:17:20 pppoe,ppp,info RDS: initializing...
mar/02 00:17:20 pppoe,ppp,info RDS: connecting...
mar/02 00:17:30 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:17:30 pppoe,ppp,info RDS: disconnected
mar/02 00:17:30 script,info Main connection DOWN. Enabling eth12
mar/02 00:17:30 system,info device changed
mar/02 00:17:40 pppoe,ppp,info RDS: initializing...
mar/02 00:17:40 pppoe,ppp,info RDS: connecting...
mar/02 00:17:50 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:17:50 pppoe,ppp,info RDS: disconnected
mar/02 00:17:50 script,info Main connection DOWN. Enabling eth12
mar/02 00:17:50 system,info device changed
mar/02 00:18:00 pppoe,ppp,info RDS: initializing...
mar/02 00:18:00 pppoe,ppp,info RDS: connecting...
mar/02 00:18:10 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:18:10 pppoe,ppp,info RDS: disconnected
mar/02 00:18:10 script,info Main connection DOWN. Enabling eth12
mar/02 00:18:10 system,info device changed
mar/02 00:18:20 pppoe,ppp,info RDS: initializing...
mar/02 00:18:20 pppoe,ppp,info RDS: connecting...
mar/02 00:18:31 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:18:31 pppoe,ppp,info RDS: disconnected
mar/02 00:18:31 script,info Main connection DOWN. Enabling eth12
mar/02 00:18:31 system,info device changed
mar/02 00:18:41 pppoe,ppp,info RDS: initializing...
mar/02 00:18:41 pppoe,ppp,info RDS: connecting...
mar/02 00:18:51 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:18:51 pppoe,ppp,info RDS: disconnected
mar/02 00:18:51 system,info device changed
mar/02 00:18:51 script,info Main connection DOWN. Enabling eth12
mar/02 00:19:01 pppoe,ppp,info RDS: initializing...
mar/02 00:19:01 pppoe,ppp,info RDS: connecting...
mar/02 00:19:11 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:19:11 pppoe,ppp,info RDS: disconnected
mar/02 00:19:11 system,info device changed
mar/02 00:19:11 script,info Main connection DOWN. Enabling eth12
mar/02 00:19:21 pppoe,ppp,info RDS: initializing...
mar/02 00:19:21 pppoe,ppp,info RDS: connecting...
mar/02 00:19:31 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:19:31 pppoe,ppp,info RDS: disconnected
mar/02 00:19:31 system,info device changed
mar/02 00:19:31 script,info Main connection DOWN. Enabling eth12
mar/02 00:19:34 pppoe,ppp,info RDS: initializing...
mar/02 00:19:34 pppoe,ppp,info RDS: connecting...
mar/02 00:19:34 system,info device changed by admin
mar/02 00:19:44 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:19:44 pppoe,ppp,info RDS: disconnected
mar/02 00:19:44 pppoe,ppp,info RDS: initializing...
mar/02 00:19:44 pppoe,ppp,info RDS: connecting...
mar/02 00:19:44 system,info device changed
mar/02 00:19:44 script,info Main connection DOWN. Enabling eth12
mar/02 00:19:54 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:19:54 pppoe,ppp,info RDS: disconnected
mar/02 00:19:54 system,info device changed
mar/02 00:19:54 script,info Main connection DOWN. Enabling eth12
mar/02 00:19:54 pppoe,ppp,info RDS: initializing...
mar/02 00:19:54 pppoe,ppp,info RDS: connecting...
mar/02 00:20:04 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:20:04 pppoe,ppp,info RDS: disconnected
mar/02 00:20:04 system,info device changed
mar/02 00:20:04 script,info Main connection DOWN. Enabling eth12
mar/02 00:20:05 pppoe,ppp,info RDS: initializing...
mar/02 00:20:05 pppoe,ppp,info RDS: connecting...
mar/02 00:20:14 system,info ppp profile <RDS> changed by admin
mar/02 00:20:15 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:20:15 pppoe,ppp,info RDS: disconnected
mar/02 00:20:15 system,info device changed
mar/02 00:20:15 script,info Main connection DOWN. Enabling eth12
mar/02 00:20:16 pppoe,ppp,info RDS: initializing...
mar/02 00:20:16 pppoe,ppp,info RDS: connecting...
mar/02 00:20:26 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:20:26 pppoe,ppp,info RDS: disconnected
mar/02 00:20:26 system,info device changed
mar/02 00:20:26 script,info Main connection DOWN. Enabling eth12
mar/02 00:20:29 pppoe,ppp,info RDS: initializing...
mar/02 00:20:29 pppoe,ppp,info RDS: connecting...
mar/02 00:20:40 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:20:40 pppoe,ppp,info RDS: disconnected
mar/02 00:20:40 system,info device changed
mar/02 00:20:40 script,info Main connection DOWN. Enabling eth12
mar/02 00:20:46 pppoe,ppp,info RDS: initializing...
mar/02 00:20:46 pppoe,ppp,info RDS: connecting...
mar/02 00:20:56 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:20:56 pppoe,ppp,info RDS: disconnected
mar/02 00:20:56 system,info device changed
mar/02 00:20:56 script,info Main connection DOWN. Enabling eth12
mar/02 00:21:06 pppoe,ppp,info RDS: initializing...
mar/02 00:21:06 pppoe,ppp,info RDS: connecting...
mar/02 00:21:17 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:21:17 pppoe,ppp,info RDS: disconnected
mar/02 00:21:17 system,info device changed
mar/02 00:21:17 script,info Main connection DOWN. Enabling eth12
mar/02 00:21:27 pppoe,ppp,info RDS: initializing...
mar/02 00:21:27 pppoe,ppp,info RDS: connecting...
mar/02 00:21:37 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:21:37 pppoe,ppp,info RDS: disconnected
mar/02 00:21:37 system,info device changed
mar/02 00:21:37 script,info Main connection DOWN. Enabling eth12
mar/02 00:21:47 pppoe,ppp,info RDS: initializing...
mar/02 00:21:47 pppoe,ppp,info RDS: connecting...
mar/02 00:21:57 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:21:57 pppoe,ppp,info RDS: disconnected
mar/02 00:21:57 system,info device changed
mar/02 00:21:57 script,info Main connection DOWN. Enabling eth12
mar/02 00:22:07 pppoe,ppp,info RDS: initializing...
mar/02 00:22:07 pppoe,ppp,info RDS: connecting...
mar/02 00:22:17 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:22:17 pppoe,ppp,info RDS: disconnected
mar/02 00:22:17 system,info device changed
mar/02 00:22:17 script,info Main connection DOWN. Enabling eth12
mar/02 00:22:27 pppoe,ppp,info RDS: initializing...
mar/02 00:22:27 pppoe,ppp,info RDS: connecting...
mar/02 00:22:37 pppoe,ppp,info RDS: terminating... - disconnected
mar/02 00:22:37 pppoe,ppp,info RDS: disconnected
mar/02 00:22:37 system,info device changed
mar/02 00:22:37 script,info Main connection DOWN. Enabling eth12
mar/02 00:22:47 pppoe,ppp,info RDS: initializing...
mar/02 00:22:47 pppoe,ppp,info RDS: connecting...
mar/02 00:22:50 interface,info ether1 link down
mar/02 00:22:50 system,info device changed by admin
mar/02 00:22:50 pppoe,ppp,info RDS: terminating...
mar/02 00:22:50 pppoe,ppp,info RDS: disconnected
mar/02 00:22:50 pppoe,ppp,info RDS: initializing...
mar/02 00:22:50 pppoe,ppp,info RDS: connecting...
mar/02 00:22:50 pppoe,ppp,info RDS: terminating...
mar/02 00:22:50 pppoe,ppp,info RDS: disconnected
mar/02 00:22:50 pppoe,ppp,info RDS: initializing...
mar/02 00:22:50 pppoe,ppp,info RDS: connecting...
mar/02 00:22:50 script,info Main connection DOWN. Enabling eth12
mar/02 00:22:50 system,info device changed
mar/02 00:22:50 system,info device changed
mar/02 00:22:50 script,info Main connection DOWN. Enabling eth12
mar/02 00:22:51 system,info device changed by admin
mar/02 00:22:51 pppoe,ppp,info RDS: terminating...
mar/02 00:22:51 pppoe,ppp,info RDS: disconnected
mar/02 00:22:51 pppoe,ppp,info RDS: initializing...
mar/02 00:22:51 pppoe,ppp,info RDS: connecting...
mar/02 00:22:51 script,info Main connection DOWN. Enabling eth12
mar/02 00:22:51 system,info device changed
mar/02 00:22:56 interface,info ether1 link up (speed 1G, full duplex)
mar/02 00:22:57 pppoe,ppp,info RDS: authenticated
mar/02 00:22:57 pppoe,ppp,info RDS: connected
mar/02 00:22:57 script,info Main connection UP. Disabling eth12
mar/02 00:22:57 system,info device changed
mar/02 00:22:57 interface,info ether12 link down