I posted a couple months ago about using an RB750G as a PPPoE server for a chunk of clients - it works great except for one small issue. Every few seconds/minutes (varies from 10 seconds to 10 minutes, usually closer to once per minute) I seem to lose the ethernet link between the ADSL2 modems (SpeedStream 4300) and the 750G. Locking the port to 10mbit/half duplex will make it stable, but it makes the ethernet the bottleneck (12/1 connections)
The RB is running ros4.16 with 2.28 firmware installed.
Try a different physical port. Usually port 1 uses the CPU’s built in Ethernet interface while 2-5 use a dedicated Ethernet chip. So if you’re using Eth1 on the RB750, try moving to Eth2 instead, and vice versa.
This used to happen to us all the time with the RB532 and some DSL or Cable modems.
Unluckily theres 3 modems in load balance, they’re currently connected to ports 3,4,5 so most likely the problem wouldn’t exist if it was on port 1. I have verified it doesn’t occur when using a RB750, but I do run out of CPU. I suspect a RB493AH may be my best reasonable cost/low-power solution.
Would be messy without a managed/vlan switch. I have the Speedstream 4300’s configured as dumb bridges, have the 750G acting as the DSL PPPoE clients (gets me two usable IPs instead of just 1 with the router eating up the second…)
Went out there and replaced the RB750G setup with an RB493AH (I had one onhand, yay) and noticed the uplink radio (nanostation M5)'s lan port kept blinking completely off for a couple seconds at a time. Totally explains the rest of the network issues I was seeing.
I’m guessing I’ve either got a saggy power supply or a bad routerboard. Either one is a definite possibility! Its not repeating itself with the RB493AH, so far.