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~$ R
R version 3.4.1 (2017-06-30) -- "Single Candle"
Copyright (C) 2017 The R Foundation for Statistical Computing
Platform: x86_64-redhat-linux-gnu (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

  Natural language support but running in an English locale

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

> print("I Work")
[1] "I Work"

~$ sudo rstudio-server verify-installation
~$ sudo rstudio-server status
● rstudio-server.service - RStudio Server
   Loaded: loaded (/etc/systemd/system/rstudio-server.service; enabled; vendor preset: disabled)
   Active: active (running) since Sat 2017-10-21 21:33:53 MST; 1s ago
  Process: 8300 ExecStop=/usr/bin/killall -TERM rserver (code=exited, status=0/SUCCESS)
  Process: 8346 ExecStart=/usr/lib/rstudio-server/bin/rserver (code=exited, status=0/SUCCESS)
 Main PID: 8349 (rserver)
   CGroup: /system.slice/rstudio-server.service
           └─8349 /usr/lib/rstudio-server/bin/rserver

Oct 21 21:33:53 localhost.localdomain systemd[1]: Starting RStudio Server...
Oct 21 21:33:53 localhost.localdomain systemd[1]: Started RStudio Server.
~$ sudo rstudio-server restart
rsession: no process found
~$ sudo rstudio-server start
~$ sudo rstudio-server stop
rsession: no process found
~$ sudo rstudio-server start
~$ sudo rstudio-server status
● rstudio-server.service - RStudio Server
   Loaded: loaded (/etc/systemd/system/rstudio-server.service; enabled; vendor preset: disabled)
   Active: active (running) since Sat 2017-10-21 21:34:14 MST; 2s ago
  Process: 8449 ExecStop=/usr/bin/killall -TERM rserver (code=exited, status=0/SUCCESS)
  Process: 8477 ExecStart=/usr/lib/rstudio-server/bin/rserver (code=exited, status=0/SUCCESS)
 Main PID: 8480 (rserver)
   CGroup: /system.slice/rstudio-server.service
           └─8480 /usr/lib/rstudio-server/bin/rserver

Oct 21 21:34:14 localhost.localdomain systemd[1]: Starting RStudio Server...
Oct 21 21:34:14 localhost.localdomain systemd[1]: Started RStudio Server.

~$ netstat -nat | grep LISTEN
tcp        0      0 0.0.0.0:111             0.0.0.0:*               LISTEN
tcp        0      0 0.0.0.0:8787            0.0.0.0:*               LISTEN
tcp        0      0 192.168.122.1:53        0.0.0.0:*               LISTEN
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN
tcp        0      0 127.0.0.1:631           0.0.0.0:*               LISTEN
tcp        0      0 127.0.0.1:25            0.0.0.0:*               LISTEN
tcp6       0      0 :::111                  :::*                    LISTEN
tcp6       0      0 :::22                   :::*                    LISTEN
tcp6       0      0 ::1:631                 :::*                    LISTEN
tcp6       0      0 ::1:25                  :::*                    LISTEN

~$ sudo ufw allow 8787
~$ sudo ufw status
Status: active

To                         Action      From
--                         ------      ----
SSH                        ALLOW       Anywhere
224.0.0.251 mDNS           ALLOW       Anywhere
8787                       ALLOW       Anywhere
SSH (v6)                   ALLOW       Anywhere (v6)
ff02::fb mDNS              ALLOW       Anywhere (v6)
8787 (v6)                  ALLOW       Anywhere (v6)

~$ sudo systemctl status firewalld
● firewalld.service - firewalld - dynamic firewall daemon
Loaded: loaded (/usr/lib/systemd/system/firewalld.service; enabled; vendor preset: enabled)
Active: active (running) since Sat 2017-10-21 20:38:02 MST; 35min ago
Docs: man:firewalld(1)
Main PID: 2987 (firewalld)
CGroup: /system.slice/firewalld.service
        └─2987 /usr/bin/python -Es /usr/sbin/firewalld --nofork --nopid

~$ sudo firewall-cmd --zone=public --add-port=8787/tcp
Warning: ALREADY_ENABLED: '8787:tcp' already in 'public'
success
~$ sudo firewall-cmd --reload
success
~$ sudo firewall-cmd --zone=public --list-all
public (active)
target: default
icmp-block-inversion: no
interfaces: enp4s0f1
sources:
services: dhcpv6-client ssh
ports: 8787/tcp
protocols:
masquerade: no
forward-ports:
source-ports:
icmp-blocks:
rich rules: