ວິທີການຈັດການ Systemd Services ແລະ Units ໃຊ້ Systemctl ໃນ Linux
Systemctl ແມ່ນລະບົບປະໂຫຍດທີ່ເປັນລະບົບທີ່ມີຄວາມຮັບຜິດຊອບໃນການຄວບຄຸມລະບົບ systemd ແລະຜູ້ຈັດການບໍລິການ. Systemd ແມ່ນຮວບຮວມຂອງ daemons ການຄຸ້ມຄອງລະບົບ, ສິ່ງ ອຳ ນວຍຄວາມສະດວກ, ແລະຫ້ອງສະ ໝຸດ ເຊິ່ງເປັນບ່ອນທົດແທນ daemon ຂອງ System V init. Systemd ເຮັດ ໜ້າ ທີ່ເປັນສູນກາງການຈັດການແລະການຕັ້ງຄ່າ ສຳ ລັບລະບົບຄ້າຍ UNIX.
ໃນ Linux, ລະບົບນິເວດລະບົບໄດ້ຖືກຈັດຕັ້ງປະຕິບັດກ່ຽວກັບການແຈກຢາຍ Linux ແບບມາດຕະຖານສ່ວນໃຫຍ່ໂດຍມີຂໍ້ຍົກເວັ້ນ ຈຳ ນວນ ໜຶ່ງ. Systemd ແມ່ນຂະບວນການພໍ່ແມ່ຂອງທຸກໆເດເວດອື່ນທີ່ມັກແຕ່ບໍ່ແມ່ນສະ ເໝີ ໄປ.
ບົດຂຽນນີ້ມີຈຸດປະສົງໃນການສະແດງ“ ວິທີການຄວບຄຸມລະບົບແລະການບໍລິການ” ກ່ຽວກັບລະບົບທີ່ ກຳ ລັງເຮັດວຽກຢູ່.
ເລີ່ມຕົ້ນດ້ວຍລະບົບພື້ນຖານຂອງ Systemtd ແລະ Systemctl
1. ກ່ອນອື່ນ ໝົດ, ກວດເບິ່ງວ່າ systemd ຖືກຕິດຕັ້ງຢູ່ໃນລະບົບຂອງທ່ານຫຼືບໍ່, ແລະ Systemd ຕິດຕັ້ງໃນປະຈຸບັນແມ່ນຫຍັງ?
# systemctl --version systemd 215 +PAM +AUDIT +SELINUX +IMA +SYSVINIT +LIBCRYPTSETUP +GCRYPT +ACL +XZ -SECCOMP -APPARMOR
ມັນຈະແຈ້ງຈາກຕົວຢ່າງຂ້າງເທິງ, ວ່າພວກເຮົາໄດ້ຕິດຕັ້ງລະບົບ 215 ລຸ້ນແລ້ວ.
2. ກວດເບິ່ງບ່ອນທີ່ຫ້ອງສະມຸດແລະຫ້ອງສະມຸດຂອງ systemd ແລະ systemctl ຕິດຕັ້ງ.
# whereis systemd systemd: /usr/lib/systemd /etc/systemd /usr/share/systemd /usr/share/man/man1/systemd.1.gz # whereis systemctl systemctl: /usr/bin/systemctl /usr/share/man/man1/systemctl.1.gz
3. ກວດເບິ່ງວ່າ systemd ກຳ ລັງເຮັດວຽກຢູ່ຫຼືບໍ່.
# ps -eaf | grep [s]ystemd root 1 0 0 16:27 ? 00:00:00 /usr/lib/systemd/systemd --switched-root --system --deserialize 23 root 444 1 0 16:27 ? 00:00:00 /usr/lib/systemd/systemd-journald root 469 1 0 16:27 ? 00:00:00 /usr/lib/systemd/systemd-udevd root 555 1 0 16:27 ? 00:00:00 /usr/lib/systemd/systemd-logind dbus 556 1 0 16:27 ? 00:00:00 /bin/dbus-daemon --system --address=systemd: --nofork --nopidfile --systemd-activation
ແຈ້ງການ: systemd ກຳ ລັງເຮັດວຽກເປັນ daemon ຂອງພໍ່ແມ່ (PID = 1). ໃນ ຄຳ ສັ່ງຂ້າງເທິງ ps ດ້ວຍ (-e) ເລືອກຂະບວນການທັງ ໝົດ, (-a) ເລືອກທຸກຂະບວນການຍົກເວັ້ນຜູ້ ນຳ ກອງປະຊຸມແລະ (-f) ສຳ ລັບລາຍຊື່ຮູບແບບເຕັມຮູບແບບ (i. e. eaf).
ນອກຈາກນີ້, ໃຫ້ສັງເກດວົງເລັບສີ່ຫລ່ຽມໃນຕົວຢ່າງຂ້າງເທິງແລະສ່ວນທີ່ເຫຼືອຂອງຕົວຢ່າງທີ່ຕ້ອງປະຕິບັດຕາມ. ການສະແດງອອກ Square Bracket ແມ່ນສ່ວນ ໜຶ່ງ ຂອງການຈັບຄູ່ຮູບແບບຂອງລັກສະນະຂອງ grep.
4. ວິເຄາະຂະບວນການ bootd systemd.
# systemd-analyze Startup finished in 487ms (kernel) + 2.776s (initrd) + 20.229s (userspace) = 23.493s
5. ວິເຄາະເວລາໂດຍແຕ່ລະຂະບວນການໃນເກີບ.
# systemd-analyze blame 8.565s mariadb.service 7.991s webmin.service 6.095s postfix.service 4.311s httpd.service 3.926s firewalld.service 3.780s kdump.service 3.238s tuned.service 1.712s network.service 1.394s lvm2-monitor.service 1.126s systemd-logind.service ....
6. ວິເຄາະຕ່ອງໂສ້ທີ່ ສຳ ຄັນໃນເກີບ.
# systemd-analyze critical-chain The time after the unit is active or started is printed after the "@" character. The time the unit takes to start is printed after the "+" character. multi-user.target @20.222s └─mariadb.service @11.657s +8.565s └─network.target @11.168s └─network.service @9.456s +1.712s └─NetworkManager.service @8.858s +596ms └─firewalld.service @4.931s +3.926s └─basic.target @4.916s └─sockets.target @4.916s └─dbus.socket @4.916s └─sysinit.target @4.905s └─systemd-update-utmp.service @4.864s +39ms └─auditd.service @4.563s +301ms └─systemd-tmpfiles-setup.service @4.485s +69ms └─rhel-import-state.service @4.342s +142ms └─local-fs.target @4.324s └─boot.mount @4.286s +31ms └─[email \x2duuid-79f594ad\x2da332\x2d4730\x2dbb5f\x2d85d19608096 └─dev-disk-by\x2duuid-79f594ad\x2da332\x2d4730\x2dbb5f\x2d85d196080964.device @4
ສິ່ງທີ່ ສຳ ຄັນ: Systemctl ຍອມຮັບການບໍລິການ (.service), ຈຸດ mount (.mount), ເຕົ້າຮັບ (. ຊອດ) ແລະອຸປະກອນຕ່າງໆ (.device) ເປັນຫົວ ໜ່ວຍ.
7. ຂຽນທຸກຫົວ ໜ່ວຍ ທີ່ມີ.
# systemctl list-unit-files UNIT FILE STATE proc-sys-fs-binfmt_misc.automount static dev-hugepages.mount static dev-mqueue.mount static proc-sys-fs-binfmt_misc.mount static sys-fs-fuse-connections.mount static sys-kernel-config.mount static sys-kernel-debug.mount static tmp.mount disabled brandbot.path disabled .....
8. ຈົດຊື່ທຸກ ໜ່ວຍ ແລ່ນ.
# systemctl list-units UNIT LOAD ACTIVE SUB DESCRIPTION proc-sys-fs-binfmt_misc.automount loaded active waiting Arbitrary Executable File Formats File Syste sys-devices-pc...0-1:0:0:0-block-sr0.device loaded active plugged VBOX_CD-ROM sys-devices-pc...:00:03.0-net-enp0s3.device loaded active plugged PRO/1000 MT Desktop Adapter sys-devices-pc...00:05.0-sound-card0.device loaded active plugged 82801AA AC'97 Audio Controller sys-devices-pc...:0:0-block-sda-sda1.device loaded active plugged VBOX_HARDDISK sys-devices-pc...:0:0-block-sda-sda2.device loaded active plugged LVM PV Qzyo3l-qYaL-uRUa-Cjuk-pljo-qKtX-VgBQ8 sys-devices-pc...0-2:0:0:0-block-sda.device loaded active plugged VBOX_HARDDISK sys-devices-pl...erial8250-tty-ttyS0.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS0 sys-devices-pl...erial8250-tty-ttyS1.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS1 sys-devices-pl...erial8250-tty-ttyS2.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS2 sys-devices-pl...erial8250-tty-ttyS3.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS3 sys-devices-virtual-block-dm\x2d0.device loaded active plugged /sys/devices/virtual/block/dm-0 sys-devices-virtual-block-dm\x2d1.device loaded active plugged /sys/devices/virtual/block/dm-1 sys-module-configfs.device loaded active plugged /sys/module/configfs ...
9. ຂຽນທຸກຫົວ ໜ່ວຍ ທີ່ລົ້ມເຫລວ.
# systemctl --failed UNIT LOAD ACTIVE SUB DESCRIPTION kdump.service loaded failed failed Crash recovery kernel arming LOAD = Reflects whether the unit definition was properly loaded. ACTIVE = The high-level unit activation state, i.e. generalization of SUB. SUB = The low-level unit activation state, values depend on unit type. 1 loaded units listed. Pass --all to see loaded but inactive units, too. To show all installed unit files use 'systemctl list-unit-files'.
10. ກວດເບິ່ງວ່າຫົວ ໜ່ວຍ (cron.service) ຖືກເປີດໃຊ້ງານຫຼືບໍ່?.
# systemctl is-enabled crond.service enabled
11. ກວດກາເບິ່ງວ່າ ໜ່ວຍ ບໍລິການຫຼື ໜ່ວຍ ງານໃດ ກຳ ລັງເຮັດວຽກຢູ່ບໍ?
# systemctl status firewalld.service firewalld.service - firewalld - dynamic firewall daemon Loaded: loaded (/usr/lib/systemd/system/firewalld.service; enabled) Active: active (running) since Tue 2015-04-28 16:27:55 IST; 34min ago Main PID: 549 (firewalld) CGroup: /system.slice/firewalld.service └─549 /usr/bin/python -Es /usr/sbin/firewalld --nofork --nopid Apr 28 16:27:51 tecmint systemd[1]: Starting firewalld - dynamic firewall daemon... Apr 28 16:27:55 tecmint systemd[1]: Started firewalld - dynamic firewall daemon.
ຄວບຄຸມແລະຄຸ້ມຄອງການບໍລິການໂດຍໃຊ້ Systemctl
12. ລົງທະບຽນການບໍລິການທັງ ໝົດ (ລວມທັງເປີດໃຊ້ງານແລະພິການ).
# systemctl list-unit-files --type=service UNIT FILE STATE arp-ethers.service disabled auditd.service enabled [email disabled blk-availability.service disabled brandbot.service static collectd.service disabled console-getty.service disabled console-shell.service disabled cpupower.service disabled crond.service enabled dbus-org.fedoraproject.FirewallD1.service enabled ....
13. ຂ້ອຍເລີ່ມຕົ້ນ, ເລີ່ມຕົ້ນ, ຢຸດ, ໂຫຼດ, ໂຫຼດແລະກວດກາສະຖານະຂອງບໍລິການໃດ (httpd.service) ໃນ Linux.
# systemctl start httpd.service # systemctl restart httpd.service # systemctl stop httpd.service # systemctl reload httpd.service # systemctl status httpd.service httpd.service - The Apache HTTP Server Loaded: loaded (/usr/lib/systemd/system/httpd.service; enabled) Active: active (running) since Tue 2015-04-28 17:21:30 IST; 6s ago Process: 2876 ExecStop=/bin/kill -WINCH ${MAINPID} (code=exited, status=0/SUCCESS) Main PID: 2881 (httpd) Status: "Processing requests..." CGroup: /system.slice/httpd.service ├─2881 /usr/sbin/httpd -DFOREGROUND ├─2884 /usr/sbin/httpd -DFOREGROUND ├─2885 /usr/sbin/httpd -DFOREGROUND ├─2886 /usr/sbin/httpd -DFOREGROUND ├─2887 /usr/sbin/httpd -DFOREGROUND └─2888 /usr/sbin/httpd -DFOREGROUND Apr 28 17:21:30 tecmint systemd[1]: Starting The Apache HTTP Server... Apr 28 17:21:30 tecmint httpd[2881]: AH00558: httpd: Could not reliably determine the server's fully q...ssage Apr 28 17:21:30 tecmint systemd[1]: Started The Apache HTTP Server. Hint: Some lines were ellipsized, use -l to show in full.
ໝາຍ ເຫດ: ເມື່ອເຮົາໃຊ້ ຄຳ ສັ່ງເຊັ່ນ: ເລີ່ມຕົ້ນ, ເລີ່ມຕົ້ນ ໃໝ່, ຢຸດແລະໂຫຼດກັບລະບົບ systemctl, ພວກເຮົາຈະບໍ່ໄດ້ຮັບຜົນຜະລິດໃດໆຢູ່ເທິງປາຍທາງ, ຄຳ ສັ່ງສະຖານະພາບເທົ່ານັ້ນຈະພິມຜົນຜະລິດ.
14. ວິທີການເຄື່ອນໄຫວບໍລິການແລະເປີດໃຊ້ງານຫຼືປິດການບໍລິການໃນເວລາບູດ (ການບໍລິການອັດຕະໂນມັດໃນລະບົບ boot system).
# systemctl is-active httpd.service # systemctl enable httpd.service # systemctl disable httpd.service
15. ວິທີການເຮັດ ໜ້າ ກາກ (ເຮັດໃຫ້ບໍ່ສາມາດເລີ່ມຕົ້ນໄດ້) ຫຼືຍົກເລີກການບໍລິການ (httpd.service).
# systemctl mask httpd.service ln -s '/dev/null' '/etc/systemd/system/httpd.service' # systemctl unmask httpd.service rm '/etc/systemd/system/httpd.service'
16. ວິທີການຂ້າບໍລິການໂດຍໃຊ້ ຄຳ ສັ່ງ systemctl.
# systemctl kill httpd # systemctl status httpd httpd.service - The Apache HTTP Server Loaded: loaded (/usr/lib/systemd/system/httpd.service; enabled) Active: failed (Result: exit-code) since Tue 2015-04-28 18:01:42 IST; 28min ago Main PID: 2881 (code=exited, status=0/SUCCESS) Status: "Total requests: 0; Current requests/sec: 0; Current traffic: 0 B/sec" Apr 28 17:37:29 tecmint systemd[1]: httpd.service: Got notification message from PID 2881, but recepti...bled. Apr 28 17:37:29 tecmint systemd[1]: httpd.service: Got notification message from PID 2881, but recepti...bled. Apr 28 17:37:39 tecmint systemd[1]: httpd.service: Got notification message from PID 2881, but recepti...bled. Apr 28 17:37:39 tecmint systemd[1]: httpd.service: Got notification message from PID 2881, but recepti...bled. Apr 28 17:37:49 tecmint systemd[1]: httpd.service: Got notification message from PID 2881, but recepti...bled. Apr 28 17:37:49 tecmint systemd[1]: httpd.service: Got notification message from PID 2881, but recepti...bled. Apr 28 17:37:59 tecmint systemd[1]: httpd.service: Got notification message from PID 2881, but recepti...bled. Apr 28 17:37:59 tecmint systemd[1]: httpd.service: Got notification message from PID 2881, but recepti...bled. Apr 28 18:01:42 tecmint systemd[1]: httpd.service: control process exited, code=exited status=226 Apr 28 18:01:42 tecmint systemd[1]: Unit httpd.service entered failed state. Hint: Some lines were ellipsized, use -l to show in full.
ຄວບຄຸມແລະຈັດການຈຸດຈຸດຕ່າງໆໂດຍໃຊ້ Systemctl
17. ລົງທະບຽນທຸກຈຸດຂອງລະບົບ.
# systemctl list-unit-files --type=mount UNIT FILE STATE dev-hugepages.mount static dev-mqueue.mount static proc-sys-fs-binfmt_misc.mount static sys-fs-fuse-connections.mount static sys-kernel-config.mount static sys-kernel-debug.mount static tmp.mount disabled
18. ຂ້ອຍຈະຕິດຕັ້ງ, ຖອດ, ຖອນຄືນ, ຕັ້ງຄ່າຈຸດໃດຂອງລະບົບແລະຍັງກວດເບິ່ງສະຖານະຂອງຈຸດທີ່ຢູ່ເທິງລະບົບໄດ້ແນວໃດ?
# systemctl start tmp.mount # systemctl stop tmp.mount # systemctl restart tmp.mount # systemctl reload tmp.mount # systemctl status tmp.mount tmp.mount - Temporary Directory Loaded: loaded (/usr/lib/systemd/system/tmp.mount; disabled) Active: active (mounted) since Tue 2015-04-28 17:46:06 IST; 2min 48s ago Where: /tmp What: tmpfs Docs: man:hier(7) http://www.freedesktop.org/wiki/Software/systemd/APIFileSystems Process: 3908 ExecMount=/bin/mount tmpfs /tmp -t tmpfs -o mode=1777,strictatime (code=exited, status=0/SUCCESS) Apr 28 17:46:06 tecmint systemd[1]: Mounting Temporary Directory... Apr 28 17:46:06 tecmint systemd[1]: tmp.mount: Directory /tmp to mount over is not empty, mounting anyway. Apr 28 17:46:06 tecmint systemd[1]: Mounted Temporary Directory.
19. ວິທີການເຄື່ອນໄຫວ, ເປີດໃຊ້ງານຫຼືປິດຈຸດ mount ໃນເວລາ boot (auto mount ໃນລະບົບ boot).
# systemctl is-active tmp.mount # systemctl enable tmp.mount # systemctl disable tmp.mount
20. ວິທີການເຮັດ ໜ້າ ກາກ (ເຮັດໃຫ້ມັນບໍ່ສາມາດເລີ່ມຕົ້ນໄດ້) ຫຼືຍົກເລີກຈຸດເດັ່ນໃນ Linux.
# systemctl mask tmp.mount ln -s '/dev/null' '/etc/systemd/system/tmp.mount' # systemctl unmask tmp.mount rm '/etc/systemd/system/tmp.mount'
ຄວບຄຸມແລະຄຸ້ມຄອງ Sockets ໂດຍໃຊ້ Systemctl
21. ບອກທຸກຊຸດຂອງລະບົບທີ່ມີຢູ່.
# systemctl list-unit-files --type=socket UNIT FILE STATE dbus.socket static dm-event.socket enabled lvm2-lvmetad.socket enabled rsyncd.socket disabled sshd.socket disabled syslog.socket static systemd-initctl.socket static systemd-journald.socket static systemd-shutdownd.socket static systemd-udevd-control.socket static systemd-udevd-kernel.socket static 11 unit files listed.
22. ຂ້ອຍຈະເລີ່ມຕົ້ນ, ເລີ່ມຕົ້ນ, ຢຸດ, ໂຫຼດ ໃໝ່ ແລະກວດສອບສະຖານະຂອງຊັອກເກັດ (ຕົວຢ່າງ: cups.socket) ໃນ Linux.
# systemctl start cups.socket # systemctl restart cups.socket # systemctl stop cups.socket # systemctl reload cups.socket # systemctl status cups.socket cups.socket - CUPS Printing Service Sockets Loaded: loaded (/usr/lib/systemd/system/cups.socket; enabled) Active: active (listening) since Tue 2015-04-28 18:10:59 IST; 8s ago Listen: /var/run/cups/cups.sock (Stream) Apr 28 18:10:59 tecmint systemd[1]: Starting CUPS Printing Service Sockets. Apr 28 18:10:59 tecmint systemd[1]: Listening on CUPS Printing Service Sockets.
23. ວິທີການໃຊ້ຊັອກເກັດແລະເປີດໃຊ້ງານຫຼືປິດໃຊ້ງານໄດ້ໃນເວລາບູດ (ຊັອດ autostart ໃນລະບົບ boot).
# systemctl is-active cups.socket # systemctl enable cups.socket # systemctl disable cups.socket
24. ວິທີການເຮັດ ໜ້າ ກາກ (ເຮັດໃຫ້ມັນບໍ່ສາມາດເລີ່ມຕົ້ນໄດ້) ຫຼືຖອດຊັອກເກັດ (ຈອກ. ເຊືອກ).
# systemctl mask cups.socket ln -s '/dev/null' '/etc/systemd/system/cups.socket' # systemctl unmask cups.socket rm '/etc/systemd/system/cups.socket'