I understand it can be done, I even found the following commands that theoretically should make it work, but all that happens is a constant loop of failed authentication. I haven't done any networking in 10 years, and while I understand some terminology, and essentially what is being done by the commands, I have no idea how to trouble shoot the issue.

/interface vlan
add interface=ether1 name=e1-v201 vlan-id=201

/interface pppoe-client
add add-default-route=yes disabled=no interface=e1-v201 name=pppoe-out1 password=password user=username

I get that what is happening is that CenturyLink uses VLAN 201 and I am tagging that on the internet port and then making it a PPPoE client. What I don't understand is why it won't authenticate. There was the following instruction as well, but I may not have applied it correctly, as there were no details on how to do so.

Please make sure that your firewall settings and NAT translation uses the pppoe-out1 interface.

I am completely new to both the Mikrotik router, which is model RB750Gr3, and CenturyLink. I optimistically thought I could just follow the instructions, and have working internet, so did not even accept the Centurylink modem. I am operating on the assumption that the connection works, but have no way to test it on my end. I am really hoping someone who has ran this specific configuration (using Mikrotik router to bypass centurylink modem), can give me a step by step on how to set it up, as I have 0 familiarity with the RouterOS or bypassing a modem. Oh, my RouterOS version is 6.40 something, but I can't get the exact number without switching off my old connection, in which I lose internet. Baring someone able to give me a step by step, I would like to know if the firewall/Nat settings could be what is causing authentication issues, and if so how to resolve them, and I also saw mention of packet sizes possibly needed to be manually changed, but I tweaked what I could find and either I changed the wrong setting or didn't change the right one.

Regardless, really hoping someone can come through for me ASAP so I don't have to pay for two internet connections while trying to get the new one to work.

did you get this figured out?

You replied to a really old post...