I tested everything, pppoe client is working correctly. @dongjunbo Can you please do the following:

I tested all is fine. So it must be something else. I found an issue in the pppoe-server code which was supposed to be released, but weren't. (local auth isn't working, rolling release has the latest code already in).
Other than that, the ppp client in rc8 is just fine, I created a pppoe server (vyos rc8) and used another vyos box (rc8) as client, no issues at all.

@dongjunbo , @syncer
The ppp client hasn't been removed, the old pppoe-server packages was a bunch of scripts utilizing rp-pppoe. I have a look into rc8, the rolling images have the client on board (ipsec l2tp would otherwise fail as well).
I'm gonna test a fresh install and have a look into your config.

In T1031#26490, @syncer wrote:

@hagbard it's not really about server, but about client
wondering if we may need ppp for client part

@hagbard it's not really about server, but about client
wondering if we may need ppp for client part

I can't reproduce it @patrickbrandao. can you please detail out of what you did?

XL710 is working with VyOS 1.2.0-rolling+201811170337

I will check fix soon.
By creating tunnels without remote side I mean something like:

ip tunnel add sit1 mode sit local 192.168.20.20 ttl 64

This is "vanilla way", as I understand.

Found another bug. Routes are shown via received-routes but with a wrong next-hop address (:: instead of fe80::465:1337:1 in my case) and they are not installed in the FIB.

admin@rt-1:~$ show ipv6 bgp neighbors fe80::465:1337:1 routes

I'm going to keep this task still open till the end of the week to catch eventual bugs.

build-ami is obsolete and never was intended for 1.2 but 1.1
therefore it will not start work and will be removed at some point in favor of aws target

Just to confirm, I tested this with RC8 and unfortunately, it still does not work.