11 Cron Tsara Tsara Tsarukan Aiki a cikin Linux

A cikin wannan labarin zamu sake dubawa mu ga yadda zamu tsara da gudanar da ayyuka a bango ta atomatik a tsaka-tsaka ta amfani da umarnin Crontab. Yin aiki mai yawa da hannu babban aiki ne mai ba da izini ga mai gudanar da tsarin. Irin wannan tsari zai iya zama jadawalin kuma ya gudana ta atomatik a bango ba tare da sa hannun mutum ta amfani da cron daemon a cikin Linux ko tsarin aiki irin na Unix ba.

Misali, zaku iya aiwatar da aiki da kai tsaye kamar madadin, tsara jadawalin sabunta bayanai da aiki tare da fayiloli da yawa. Cron ne maiemon don gudanar da ayyukan jadawalin. Cron yana farkawa kowane minti kuma yana duba jadawalin ayyuka cikin wahala. Crontab (CRON TABle) tebur ne inda zamu iya tsara irin waɗannan ayyukan da aka maimaita.

Tukwici: Kowane mai amfani na iya samun crontab na kansa don ƙirƙirar, gyara da share ayyuka. Ta hanyar tsoho cron yana ba masu amfani damar, duk da haka zamu iya ƙuntata ƙara shigarwa a cikin fayil /etc/cron.deny.

Fayil na Crontab yana ƙunshe da umarni kowane layi kuma suna da filaye shida a zahiri kuma sun rabu da sarari ko tab. Farkon filaye biyar suna wakiltar lokaci don gudanar da ayyuka kuma filin ƙarshe shine don umarni.

  1. Minti (riƙe ƙimomi tsakanin 0-59)
  2. Sa'a (riƙe ƙimomi tsakanin 0-23)
  3. Ranar Watan (riƙe ƙimomi tsakanin 1-31)
  4. Watan shekara (riƙe ƙimomi tsakanin 1-12 ko Jan-Dec, zaku iya amfani da haruffa uku na farko na sunan kowane wata watau Jan ko Jun.)
  5. Ranar mako (riƙe dabi'u tsakanin 0-6 ko Sun-Sat, A nan kuma zaku iya amfani da haruffa uku na farko na sunan kowace rana watau Sun ko Wed.)
  6. Umarni

Jera ko sarrafa aikin tare da umarnin crontab tare da -l zaɓi don mai amfani na yanzu.

# crontab -l

00 10 * * * /bin/ls >/ls.txt

Don shirya shigarwar crontab, yi amfani da -e zaɓi kamar yadda aka nuna a ƙasa. A cikin misalin da ke ƙasa zai buɗe ayyukan jadawalin a cikin editan VI. Yi canje-canje masu buƙata kuma daina latsawa: mabuɗan wq wanda ke adana saitin ta atomatik.

# crontab -e

Don lissafa ayyukan da aka tsara na wani mai amfani da ake kira tecmint ta amfani da zaɓi kamar -u (Mai amfani) da -l (Jerin).

# crontab -u tecmint -l

no crontab for tecmint

Lura: Mai amfani da tushen kawai ke da cikakkiyar dama don ganin sauran masu amfani sun shigo ciki. Mai amfani da al'ada ba zai iya kallon shi wasu ba.

Tsanaki: Crontab tare da -r siga zai cire cikakken ayyukan da aka tsara ba tare da tabbaci daga crontab ba. Yi amfani da -i zaɓi kafin share crontab ɗin mai amfani.

# crontab -r

crontab tare da -i zaɓi zai sa ku tabbatar daga mai amfani kafin share crontab ɗin mai amfani.

# crontab -i -r

crontab: really delete root's crontab?

  1. Asterik (*) - Yi daidai da dukkan ƙimomin da ke cikin filin ko kowane irin ƙimar da zai iya yi.
  2. Jan layi (-) - Don ayyana kewayon.
  3. Slash (/) - Filin farko/10 ma'ana kowane minti goma ko ƙari na kewayo.
  4. Waƙafi (,) - Don raba abubuwa.

Mai gudanar da tsarin zai iya amfani da predefine cron directory kamar yadda aka nuna a ƙasa.

  1. /etc/cron.d
  2. /etc/cron.daily
  3. /etc/cron.hourly
  4. /etc/cron.watanni
  5. /etc/cron.weekly

Ayyukan da ke ƙasa suna share fayilolin wofi da kundin adireshi daga/tmp da 12:30 na safe kowace rana. Kuna buƙatar ambaci sunan mai amfani don aiwatar da umarnin crontab. A ƙasa misali tushen mai amfani yana yin aikin cron.

# crontab -e

30 0 * * *   root   find /tmp -type f -empty -delete

Kuna buƙatar maye gurbin fannoni biyar na umarnin cron tare da kalma idan kuna son amfani da wannan.

A ƙasa misalin command1 da command2 suna gudana kowace rana.

# crontab -e

@daily <command1> && <command2>

Ta hanyar tsoho cron aika wasiƙa zuwa asusun mai amfani wanda ke aiwatar da cronjob. Idan kuna son musaki shi ƙara aikin cron ɗinku kwatankwacin misalin ƙasa. Amfani da>/dev/null 2> & 1 zaɓi a ƙarshen fayil ɗin zai sake tura duk abubuwan da aka fitar na sakamakon cron ƙarƙashin/dev/null.

 crontab -e
* * * * * >/dev/null 2>&1

conclusionarshe: Aiki na ayyuka na iya taimaka mana don aiwatar da aikinmu mafi kyawun hanyoyi, kuskure kyauta da inganci. Kuna iya tura shafin hannu na crontab don ƙarin bayanin buga 'man crontab' umarni a cikin tashar ku.