Вопрос ISP Ростелеком, или как я настраивал PPPoE-подключение в Fedora

$ dnf info rp-pppoe

Установленные пакеты
Имя          : rp-pppoe
Версия       : 3.12
Выпуск       : 10.fc27
Архитектура  : x86_64
Размер       : 290 k
Источник     : rp-pppoe-3.12-10.fc27.src.rpm
Репозиторий  : @System
Из репозитор : fedora
Краткое опис : A PPP over Ethernet client (for xDSL support).
URL          : http://www.roaringpenguin.com/pppoe/
Лицензия     : GPLv2+                                                                                                                                        
Описание     : PPPoE (Point-to-Point Protocol over Ethernet) is a protocol used by                                                                           
             : many ADSL Internet Service Providers. This package contains the                                                                               
             : Roaring Penguin PPPoE client, a user-mode program that does not                                                                               
             : require any kernel modifications. It is fully compliant with RFC 2516,                                                                        
             : the official PPPoE specification.

nameserver 8.8.8.8
nameserver 8.8.4.4

$ ifconfig
enp1s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        ether 00:25:22:bb:5f:e9  txqueuelen 1000  (Ethernet)
        RX packets 69790  bytes 93509196 (89.1 MiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 43016  bytes 4090769 (3.9 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 1  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 28  bytes 1680 (1.6 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 28  bytes 1680 (1.6 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

$ sudo pppoe-setup

Welcome to the PPPoE client setup.  First, I will run some checks on
your system to make sure the PPPoE client is installed properly...


LOGIN NAME

Enter your Login Name (default alex): szt   # У Ростелекома в качестве и логина и пароля (будет запрошен далее) - аббревиатура szt.

INTERFACE

Enter the Ethernet interface connected to the PPPoE modem
For Solaris, this is likely to be something like /dev/hme0.
For Linux, it will be ethX, where 'X' is a number.
(default eth0): enp1s0

Do you want the link to come up on demand, or stay up continuously?
If you want it to come up on demand, enter the idle time in seconds
after which the link should be dropped.  If you want the link to
stay up permanently, enter 'no' (two letters, lower-case.)
NOTE: Demand-activated links do not interact well with dynamic IP
addresses.  You may have some problems with demand-activated links.
Enter the demand value (default no): 

DNS

Please enter the IP address of your ISP's primary DNS server.
If your ISP claims that 'the server will provide dynamic DNS addresses',
enter 'server' (all lower-case) here.
If you just press enter, I will assume you know what you are
doing and not modify your DNS setup.
Enter the DNS information here: # Просто жмем Enter, т.к. resolv.conf уже сконфигурирован ранее, см. выше.

PASSWORD

Please enter your Password: # szt, как было сказано ранее.
Please re-enter your Password: # szt, как было сказано ранее.

USERCTRL

Please enter 'yes' (three letters, lower-case.) if you want to allow
normal user to start or stop DSL connection (default yes): 

FIREWALLING

Please choose the firewall rules to use.  Note that these rules are
very basic.  You are strongly encouraged to use a more sophisticated
firewall setup; however, these will provide basic security.  If you
are running any servers on your machine, you must choose 'NONE' and
set up firewalling yourself.  Otherwise, the firewall rules will deny
access to all standard servers like Web, e-mail, ftp, etc.  If you
are using SSH, the rules will block outgoing SSH connections which
allocate a privileged source port.

The firewall choices are:
0 - NONE: This script will not set any firewall rules.  You are responsible
          for ensuring the security of your machine.  You are STRONGLY
          recommended to use some kind of firewall rules.
1 - STANDALONE: Appropriate for a basic stand-alone web-surfing workstation
2 - MASQUERADE: Appropriate for a machine acting as an Internet gateway
                for a LAN
Choose a type of firewall (0-2): 1 # В принципе, неважно, особенно если зайдете потом в "Настройки сетевого экрана" и подредактируете правила более тщательно, чем это сделал бы за вас скрипт.

Start this connection at boot time

Do you want to start this connection at boot time?
Please enter no or yes (default no):yes

** Summary of what you entered **

Ethernet Interface: enp1s0
User name:          szt
Activate-on-demand: No
DNS:                Do not adjust
Firewalling:        STANDALONE
User Control:       yes
Accept these settings and adjust configuration files (y/n)? y
Adjusting /etc/sysconfig/network-scripts/ifcfg-ppp0
Adjusting /etc/ppp/chap-secrets and /etc/ppp/pap-secrets
  (But first backing it up to /etc/ppp/chap-secrets.bak)
  (But first backing it up to /etc/ppp/pap-secrets.bak)



Congratulations, it should be all set up!

Type '/sbin/ifup ppp0' to bring up your xDSL link and '/sbin/ifdown ppp0'
to bring it down.
Type '/sbin/pppoe-status /etc/sysconfig/network-scripts/ifcfg-ppp0'
to see the link status.

$ sudo /sbin/ifup ppp0

$ sudo /sbin/pppoe-status /etc/sysconfig/network-scripts/ifcfg-ppp0
pppoe-status: Link is up and running on interface ppp0
4: ppp0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1492 qdisc fq_codel state UNKNOWN group default qlen 3
    link/ppp 
    inet 100.81.125.79 peer 100.65.40.1/32 scope global ppp0
       valid_lft forever preferred_lft forever
       
$ ping google.com
PING google.com (209.85.233.139) 56(84) bytes of data.
64 bytes from lr-in-f139.1e100.net (209.85.233.139): icmp_seq=1 ttl=47 time=21.2 ms
64 bytes from lr-in-f139.1e100.net (209.85.233.139): icmp_seq=2 ttl=47 time=19.1 ms
64 bytes from lr-in-f139.1e100.net (209.85.233.139): icmp_seq=3 ttl=47 time=20.2 ms
^C
--- google.com ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2002ms
rtt min/avg/max/mdev = 19.137/20.228/21.281/0.883 ms

#/etc/ssh/sshd_config
ClientAliveInterval 60
ClientAliveCountMax 3
TCPKeepAlive no

sudo /sbin/ifup ppp0
ppp0            no-device

sudo pppoe-start