daemon administratie: systemctl
Sedert 2016 gebruiken redhat, debian, ubuntu en linux mint het pakket systemd voor service beheer
Een uitgebreide uitleg vind je hier: digital ocean systemd.
We tonen kort de belangrijkste funkties:
- status van openssh tonen: [
systemctl
status naam.service]
user@mint18-srv ~ $ sudo systemctl status ssh.service
● ssh.service - OpenBSD Secure Shell server Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enab Active: active (running) since Wed 2017-05-31 15:19:38 CEST; 1h 8min ago Main PID: 2620 (sshd) CGroup: /system.slice/ssh.service └─2620 /usr/sbin/sshd -D May 31 15:19:38 mint18-srv systemd[1]: Starting OpenBSD Secure Shell server... May 31 15:19:38 mint18-srv sshd[2620]: Server listening on 0.0.0.0 port 22. May 31 15:19:38 mint18-srv sshd[2620]: Server listening on :: port 22. May 31 15:19:38 mint18-srv systemd[1]: Started OpenBSD Secure Shell server. May 31 15:55:57 mint18-srv sshd[2924]: Accepted password for bert from 127.0.0.1 May 31 15:55:57 mint18-srv sshd[2924]: pam_unix(sshd:session): session opened ..
- ssh-daemon stoppen: [
systemctl
stop naam.service]
user@mint18-srv ~ $ sudo systemctl stop ssh.service
(de command line zegt niets we moeten de status opvragen ...)
user@mint18-srv ~ $ systemctl status ssh.service
● ssh.service - OpenBSD Secure Shell server Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enab Active: inactive (dead) since Wed 2017-05-31 16:31:10 CEST; 4s ago Main PID: 2620 (code=exited, status=0/SUCCESS) ... May 31 16:31:10 mint18-srv systemd[1]: Stopping OpenBSD Secure Shell server... May 31 16:31:10 mint18-srv systemd[1]: Stopped OpenBSD Secure Shell server.
- ssh-daemon starten: [
systemctl
start naam.service]
user@mint18-srv ~ $ sudo systemctl start ssh.service
user@mint18-srv ~ $ systemctl status ssh.service
● ssh.service - OpenBSD Secure Shell server Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled) Active: active (running) since Wed 2017-05-31 16:36:19 CEST; 5s ago Main PID: 3046 (sshd) CGroup: /system.slice/ssh.service └─3046 /usr/sbin/sshd -D May 31 16:36:19 mint18-srv systemd[1]: Starting OpenBSD Secure Shell server... May 31 16:36:19 mint18-srv sshd[3046]: Server listening on 0.0.0.0 port 22. May 31 16:36:19 mint18-srv sshd[3046]: Server listening on :: port 22. May 31 16:36:19 mint18-srv systemd[1]: Started OpenBSD Secure Shell server.
- ssh-daemon herstarten: [
systemctl
restart naam.service]
herstarten is een stop gevolgd door een start
user@mint18-srv ~ $ sudo systemctl restart ssh.service
user@mint18-srv ~ $ systemctl status ssh.service
● ssh.service - OpenBSD Secure Shell server Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled) Active: active (running) since Wed 2017-05-31 16:40:56 CEST; 1s ago Main PID: 3055 (sshd) CGroup: /system.slice/ssh.service └─3055 /usr/sbin/sshd -D May 31 16:40:56 mint18-srv systemd[1]: Starting OpenBSD Secure Shell server... May 31 16:40:56 mint18-srv sshd[3055]: Server listening on 0.0.0.0 port 22. May 31 16:40:56 mint18-srv sshd[3055]: Server listening on :: port 22. May 31 16:40:56 mint18-srv systemd[1]: Started OpenBSD Secure Shell server.
Merk op dat de PID veranderd is van 3046 naar 3055
- ssh-daemon reloaden: [
systemctl
reload naam.service]
reloaden is een herinladen van de config-file (meestal na aanpassingen)
user@mint18-srv ~ $ sudo systemctl reload ssh.service
user@mint18-srv ~ $ systemctl status ssh.service
● ssh.service - OpenBSD Secure Shell server Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled) Active: active (running) since Wed 2017-05-31 16:40:56 CEST; 4min 21s ago Process: 3064 ExecReload=/bin/kill -HUP $MAINPID (code=exited, status=0/SUCCESS) Main PID: 3055 (sshd) CGroup: /system.slice/ssh.service └─3055 /usr/sbin/sshd -D May 31 16:40:56 mint18-srv systemd[1]: Starting OpenBSD Secure Shell server... May 31 16:40:56 mint18-srv sshd[3055]: Server listening on 0.0.0.0 port 22. May 31 16:40:56 mint18-srv sshd[3055]: Server listening on :: port 22. May 31 16:40:56 mint18-srv systemd[1]: Started OpenBSD Secure Shell server. May 31 16:45:16 mint18-srv systemd[1]: Reloading OpenBSD Secure Shell server. May 31 16:45:16 mint18-srv sshd[3055]: Received SIGHUP; restarting. May 31 16:45:16 mint18-srv systemd[1]: Reloaded OpenBSD Secure Shell server. May 31 16:45:16 mint18-srv sshd[3055]: Server listening on 0.0.0.0 port 22.
De PID is nu gelijk gebleven ...
- ssh-daemon dis-ablen: [
systemctl
disable naam.service]
disable, betekent dat de service niet meer automatisch wordt opgestart bij booten van je server
user@mint18-srv ~ $ sudo systemctl disable ssh.service
Synchronizing state of ssh.service with SysV init with /lib/systemd/systemd-sysv-install... Executing /lib/systemd/systemd-sysv-install disable ssh insserv: warning: current start runlevel(s) (empty) of script `ssh' overrides LSB defaults (2 3 4 5). insserv: warning: current stop runlevel(s) (2 3 4 5) of script `ssh' overrides LSB defaults (empty). Removed symlink /etc/systemd/system/sshd.service.
user@mint18-srv ~ $ systemctl status ssh.service
● ssh.service - OpenBSD Secure Shell server Loaded: loaded (/lib/systemd/system/ssh.service; disabled; vendor preset: enabled) Active: active (running) since di 2017-06-06 12:32:52 CEST; 6h ago
Hoewel bij de volgende system restart de service niet meer automatisch zal opstarten, wordt die nu met rust gelaten, en blijft de ssh.service draaien.
We herstarten de machine:
user@mint18-srv ~ ~$ sudo init 6
Connection to 192.168.5.240 closed by remote host. Connection to 192.168.5.240 closed.
... en proberen nadien terug in te loggen:
frank@system3 ~ $ ssh user@192.168.5.240
ssh: connect to host 192.168.5.240 port 22: Connection refused
- ssh-daemon en-ablen: [
systemctl
enable naam.service]
enable, betekent dat de service automatisch zal worden opgestart bij elke boot van je server.
bij het installeren van een service metapt
wordt een service normaal gezien automatisch ge-enabled.
user@mint18-srv ~ $ sudo systemctl enable ssh.service
Synchronizing state of ssh.service with SysV init with /lib/systemd/systemd-sysv-install... Executing /lib/systemd/systemd-sysv-install enable ssh insserv: warning: current start runlevel(s) (empty) of script `ssh' overrides LSB defaults (2 3 4 5). insserv: warning: current stop runlevel(s) (2 3 4 5) of script `ssh' overrides LSB defaults (empty). Created symlink from /etc/systemd/system/sshd.service to /lib/systemd/system/ssh.service.
- oefening: probeer de voorbeelden van hierboven met
systemctl
op de service httpd op je eigen Rocky LX 8 systeem of
apache2 op je eigen ubuntu 20 systeem (sudo apt install apache2
)
SSH service in RedHat8 ---------------------- 33 sudo systemctl status sshd 34 sudo systemctl status sshd.service APACHE2 in RedHat8 ------------------ 37 sudo yum install httpd 60 sudo systemctl status httpd 63 sudo systemctl start httpd LYNX in RedHat8 --------------- 43 yum search lynx 48 cd /etc/yum.repos.d/ 49 ls 56 sudo dnf config-manager --set-enabled powertools 57 sudo yum install lynx APACHE testen in RedHat8 ------------------------ 65 lynx localhost