@dongjunbo What do you mean?
Could you send a real example? I don't see any issues (VyOS 1.3-stable-202207280515).

@NikolayP Try the next command:

Maybe it depends on the version of accel-ppp.
In 1.2.8:

In T4457#124584, @NikolayP wrote:

The problem seems to be in these lines:

set vpn l2tp remote-access authentication local-users username test static-ip '172.25.255.1'
set vpn l2tp remote-access client-ip-pool start '172.25.255.1'
set vpn l2tp remote-access client-ip-pool stop '172.25.255.14'

Replacing "static IP" with 172.25.255.2 makes it work in VyOS 1.3.1

set vpn l2tp remote-access authentication local-users username test static-ip '172.25.255.2'

Full corrected config for 1.3.1 from the first post:

set interfaces dummy dum4 address '4.4.4.4/32'
set interfaces ethernet eth0 address 'dhcp'
set interfaces ethernet eth1 address '192.168.6.31/24'
set service ssh
set vpn ipsec ipsec-interfaces interface 'eth1'
set vpn ipsec nat-networks allowed-network 0.0.0.0/0
set vpn ipsec nat-traversal 'enable'
set vpn l2tp remote-access authentication local-users username test password 'test'
set vpn l2tp remote-access authentication local-users username test static-ip '172.25.255.2'
set vpn l2tp remote-access authentication mode 'local'
set vpn l2tp remote-access authentication require 'mschap-v2'
set vpn l2tp remote-access client-ip-pool start '172.25.255.1'
set vpn l2tp remote-access client-ip-pool stop '172.25.255.14'
set vpn l2tp remote-access idle '1800'
set vpn l2tp remote-access ipsec-settings authentication mode 'pre-shared-secret'
set vpn l2tp remote-access ipsec-settings authentication pre-shared-secret 'test'
set vpn l2tp remote-access ipsec-settings ike-lifetime '3600'
set vpn l2tp remote-access ipsec-settings lifetime '3600'
set vpn l2tp remote-access outside-address '192.168.6.31'

The problem seems to be in these lines:

Same as Viacheslav. No issues on my tests in Ubuntu.

Don't have any issues with Ubuntu

set interfaces dummy dum0 address '192.0.2.1/32'
set interfaces dummy dum4 address '203.0.113.1/24'
set interfaces ethernet eth0 address '192.168.122.11/24'
set interfaces ethernet eth0 description 'WAN'
set vpn ipsec ipsec-interfaces interface 'eth0'
set vpn l2tp remote-access authentication local-users username test password 'test'
set vpn l2tp remote-access authentication mode 'local'
set vpn l2tp remote-access client-ip-pool start '192.168.255.2'
set vpn l2tp remote-access client-ip-pool stop '192.168.255.254'
set vpn l2tp remote-access ipsec-settings authentication mode 'pre-shared-secret'
set vpn l2tp remote-access ipsec-settings authentication pre-shared-secret 'secret'
set vpn l2tp remote-access outside-address '192.0.2.1'

@NikolayP , Looks like MTU and MPPE issue. Stoping daemon does not related to this I think.

Not sure if this is relevant to the task.
But once when shutting down a VM with VyOS 1.3.1-S1, it took a long time to shut down:

The current discussion has taken place in the vyos-api-discussion channel; results will be summarized here.

Firstly, is there any info in the logs ?

As discussed in the slack channel today, let us follow up here, as I'd like to run through some analysis, and set up a reproducer if possible.

The command works well.