Daħla
Hi kollha! Jisimni Sasha, u ilni nittestja backend (servizzi Linux u API) għal aktar minn sitt snin. L-idea tal-artiklu waslitli wara talba oħra minn ħabib tat-test biex jgħidlu x'seta' jaqra dwar il-kmandi tal-Linux qabel intervista. Tipikament, kandidat għal pożizzjoni ta' inġinier tal-QA huwa meħtieġ li jkun jaf il-kmandi bażiċi (jekk, ovvjament, jinvolvu xogħol mal-Linux), imma kif tkun taf liema kmandijiet ta' min taqra fuqhom meta tipprepara għal intervista jekk ikollok ftit jew l-ebda esperjenza bil-Linux?
Għalhekk, għalkemm dan diġà nkiteb ħafna drabi, xorta ddeċidejt li nikteb artiklu ieħor "Linux għall-jibdew" u nniżżel hawn il-kmandi bażiċi li trid tkun taf qabel kwalunkwe intervista f'dipartiment (jew kumpanija) li juża Linux. Ħsibt dwar liema kmandi u utilitajiet u b'liema parametri nuża l-aktar ta 'spiss, ġabar rispons mingħand il-kollegi tiegħi, u kkumpilatha kollha f'artiklu wieħed. L-artikolu huwa maqsum fi 3 partijiet: l-ewwel, informazzjoni qasira dwar il-baŜi tal-I/O fit-terminal Linux, imbagħad ħarsa ġenerali tal-kmandi l-aktar bażiċi, u t-tielet parti tiddeskrivi kif issolvi problemi komuni fil-Linux.
Kull kmand għandu ħafna għażliet, kollha kemm huma mhux se jkunu elenkati hawn. Dejjem tista' tidħol `bniedem <kmand>` jew `<kmand> --help` biex titgħallem aktar dwar it-tim.
Eżempju:
[user@testhost ~]$ mkdir --help Usage: mkdir [OPTION]... DIRECTORY... Create the DIRECTORY(ies), if they do not already exist. Mandatory arguments to long options are mandatory for short options too. -m, --mode=MODE set file mode (as in chmod), not a=rwx - umask -p, --parents no error if existing, make parent directories as needed -v, --verbose print a message for each created directory -Z set SELinux security context of each created directory to the default type --context[=CTX] like -Z, or if CTX is specified then set the SELinux or SMACK security context to CTX --help display this help and exit --version output version information and exit GNU coreutils online help: <http://www.gnu.org/software/coreutils/> For complete documentation, run: info coreutils 'mkdir invocation'
Jekk kmand jieħu wisq żmien biex jitlesta, tista’ ttemmha billi tikklikkja fil-console Ctrl + C (jinbagħat sinjal lill-proċess SIGINT).
Ftit dwar l-output tal-kmand
Meta proċess jibda fil-Linux, jinħolqu 3 flussi ta' data standard għal dak il-proċess: stdin, stdout и stderr. Huma nnumerati 0, 1 u 2 rispettivament. Imma issa aħna interessati stdout u, sa ċertu punt, stderr. Mill-ismijiet huwa faċli li raden li stdout jintuża biex joħroġ data, u stderr — biex turi messaġġi ta' żball. B'mod awtomatiku meta tmexxi kmand fuq Linux stdout и stderr joħroġ l-informazzjoni kollha lill-console, madankollu, jekk l-output tal-kmand huwa kbir, jista 'jkun konvenjenti li terġa' tidderieġiha għal fajl. Dan jista 'jsir, pereżempju, bħal dan:
[user@testhost ~]$ man signal > man_signal
Jekk noħorġu l-kontenut tal-fajl man_signal, allura naraw li huwa identiku għal dak li jkun jekk aħna sempliċiment mexxa l-kmand `sinjal bniedem`.
Operazzjoni ta' direzzjoni mill-ġdid `>` default li stdout. Tista' tispeċifika redirect stdout espliċitament: `1>`. Bl-istess mod, tista 'tispeċifika direzzjoni mill-ġdid stderr:`2>`. Tista 'tgħaqqad dawn l-operazzjonijiet u għalhekk tissepara l-output normali tal-kmand u l-output tal-messaġġ ta' żball:
[user@testhost ~]$ man signal 1> man_signal 2> man_signal_error_log
Redirect u stdoutU stderr f'fajl wieħed kif ġej:
[user@testhost ~]$ man signal > man_signal 2>&1
Operazzjoni ta' direzzjoni mill-ġdid `2> & 1` tfisser direzzjoni mill-ġdid stderr fl-istess post kif ordnat stdout.
Għodda oħra konvenjenti biex taħdem ma 'I/O (jew aħjar, hija għodda konvenjenti għall-komunikazzjoni bejn il-proċessi) hija pajp (Jew conveyor). Il-pipelines spiss jintużaw biex jikkomunikaw kmandi multipli: stdout kmandi huma diretti lejn stdin jmiss, u l-bqija fil-katina:
[user@testhost ~]$ ps aux | grep docker | tail -n 2
root 1045894 0.0 0.0 7512 3704 ? Sl 16:04 0:00 docker-containerd-shim -namespace moby -workdir /var/lib/docker/containerd/daemon/io.containerd.runtime.v1.linux/moby/2fbfddaf91c1bb7b9a0a6f788f3505dd7266f1139ad381d5b51ec1f47e1e7b28 -address /var/run/docker/containerd/docker-containerd.sock -containerd-binary /usr/bin/docker-containerd -runtime-root /var/run/docker/runtime-runc
531 1048313 0.0 0.0 110520 2084 pts/2 S+ 16:12 0:00 grep --color=auto docker
Kmandi bażiċi tal-Linux
pwd
Uri d-direttorju kurrenti (tax-xogħol).
[user@testhost ~]$ pwd
/home/user
data
Uri d-data u l-ħin tas-sistema kurrenti.
[user@testhost ~]$ date
Mon Dec 16 13:37:07 UTC 2019
[user@testhost ~]$ date +%s
1576503430
w
Dan il-kmand juri min huwa illoggjat fis-sistema. Barra minn hekk, uptime u LA (medja tat-tagħbija) huma murija wkoll fuq l-iskrin.
[user@testhost ~]$ w
05:47:17 up 377 days, 17:57, 1 user, load average: 0,00, 0,01, 0,05
USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT
user pts/0 32.175.94.241 05:47 2.00s 0.01s 0.00s w
ls
Stampa l-kontenut ta 'direttorju. Jekk ma tgħaddix it-triq, jintwera l-kontenut tad-direttorju attwali.
[user@testhost ~]$ pwd
/home/user
[user@testhost ~]$ ls
qqq
[user@testhost ~]$ ls /home/user
qqq
[user@testhost ~]$ ls /
bin boot cgroup dev etc home lib lib64 local lost+found media mnt opt proc root run sbin selinux srv swap sys tmp usr var
Personalment, spiss nuża l-għażliet -l (format ta' lista twila - output għal kolonna b'informazzjoni addizzjonali dwar fajls), -t (l-għażla skond il-ħin tal-modifika tal-fajl/direttorju) u -r (issortjar b'lura - flimkien ma' -t l-aktar fajls riċenti se jkunu fil-qiegħ):
[user@testhost ~]$ ls -ltr /
total 4194416
drwxr-xr-x 2 root root 4096 Jan 6 2012 srv
drwxr-xr-x 2 root root 4096 Jan 6 2012 selinux
drwxr-xr-x 2 root root 4096 Jan 6 2012 mnt
drwxr-xr-x 2 root root 4096 Jan 6 2012 media
drwx------ 2 root root 16384 Oct 1 2017 lost+found
drwxr-xr-x 2 root root 4096 Oct 1 2017 local
drwxr-xr-x 13 root root 4096 Oct 1 2017 usr
drwxr-xr-x 11 root root 4096 Apr 10 2018 cgroup
drwxr-xr-x 4 root root 4096 Apr 10 2018 run
-rw------- 1 root root 4294967296 Sep 10 2018 swap
dr-xr-xr-x 10 root root 4096 Dec 13 2018 lib
drwxr-xr-x 6 root root 4096 Mar 7 2019 opt
drwxr-xr-x 20 root root 4096 Mar 19 2019 var
dr-xr-xr-x 10 root root 12288 Apr 9 2019 lib64
dr-xr-xr-x 2 root root 4096 Apr 9 2019 bin
dr-xr-xr-x 4 root root 4096 Apr 9 2019 boot
dr-xr-xr-x 2 root root 12288 Apr 9 2019 sbin
dr-xr-xr-x 3229 root root 0 Jul 2 10:19 proc
drwxr-xr-x 34 root root 4096 Oct 28 13:27 home
drwxr-xr-x 93 root root 4096 Oct 30 16:00 etc
dr-xr-x--- 11 root root 4096 Nov 1 13:02 root
dr-xr-xr-x 13 root root 0 Nov 13 20:28 sys
drwxr-xr-x 16 root root 2740 Nov 26 08:55 dev
drwxrwxrwt 3 root root 4096 Nov 26 08:57 tmp
Hemm 2 ismijiet ta' direttorji speċjali: "."U"..". L-ewwel wieħed ifisser id-direttorju attwali, it-tieni wieħed ifisser id-direttorju ġenitur. Jistgħu jkunu konvenjenti biex jintużaw f'diversi timijiet, b'mod partikolari ls:
[user@testhost home]$ pwd
/home
[user@testhost home]$ ls ..
bin boot cgroup dev etc home lib lib64 local lost+found media mnt opt proc root run sbin selinux srv swap sys tmp usr var
[user@testhost home]$ ls ../home/user/
qqq
Hemm ukoll għażla utli biex turi fajls moħbija (li tibda minn ".") - -a:
[user@testhost ~]$ ls -a
. .. 1 .bash_history .bash_logout .bash_profile .bashrc .lesshst man_signal man_signal_error_log .mongorc.js .ssh temp test .viminfo
Tista 'wkoll tuża l-għażla -h — output f'format li jinqara mill-bniedem (oqgħod attent għad-daqsijiet tal-fajl):
[user@testhost ~]$ ls -ltrh
total 16K
-rwxrwx--x 1 user user 31 Nov 26 11:09 temp
-rw-rw-r-- 1 user user 6.0K Dec 3 16:02 1
drwxrwxr-x 2 user user 4.0K Dec 4 10:39 test
cd
Ibdel id-direttorju attwali.
[user@testhost ~]$ pwd
/home/user
[user@testhost ~]$ cd /home/
[user@testhost home]$ pwd
/home
Jekk ma tgħaddix l-isem tad-direttorju bħala argument, tintuża l-varjabbli ambjentali $ HOME, jiġifieri, id-direttorju tad-dar. Jista' jkun ukoll konvenjenti li tuża `~` hija tifsira ta' karattru speċjali $ HOME:
[user@testhost etc]$ pwd
/etc
[user@testhost etc]$ cd ~/test/
[user@testhost test]$ pwd
/home/user/test
mkdir
Oħloq direttorju.
[user@testhost ~]$ mkdir test
[user@testhost ~]$ ls -ltr
total 38184
-rw-rw-r-- 1 user user 39091284 Nov 22 14:14 qqq
drwxrwxr-x 2 user user 4096 Nov 26 10:29 test
Xi drabi għandek bżonn toħloq struttura ta' direttorju speċifika: pereżempju, direttorju f'direttorju li ma jeżistix. Biex tevita li tidħol diversi drabi wara xulxin mkdir, tista' tuża l-għażla -p — jippermettilek toħloq id-direttorji kollha neqsin fil-ġerarkija. Ukoll b'din l-għażla mkdir mhux se jirritorna żball jekk id-direttorju jeżisti.
[user@testhost ~]$ ls
qqq test
[user@testhost ~]$ mkdir test2/subtest
mkdir: cannot create directory ‘test2/subtest’: No such file or directory
[user@testhost ~]$ mkdir -p test2/subtest
[user@testhost ~]$ ls
qqq test test2
[user@testhost ~]$ ls test2/
subtest
[user@testhost ~]$ mkdir test2/subtest
mkdir: cannot create directory ‘test2/subtest’: File exists
[user@testhost ~]$ mkdir -p test2/subtest
[user@testhost ~]$ ls test2/
subtest
rm
Ħassar fajl.
[user@testhost ~]$ ls
qqq test test2
[user@testhost ~]$ rm qqq
[user@testhost ~]$ ls
test test2
Għażla -r jippermettilek li tħassar id-direttorji b'mod rikorsiv bil-kontenut kollu tagħhom, għażla -f jippermettilek tinjora l-iżbalji meta tħassar (pereżempju, dwar fajl li ma jeżistix). Dawn l-għażliet jippermettu, bejn wieħed u ieħor, tħassir garantit tal-ġerarkija kollha tal-fajls u direttorji (jekk l-utent ikollu d-drittijiet li jagħmel dan), għalhekk, għandhom jintużaw b'kawtela (eżempju taċ-ċajta klassika huwa "rm-rf /", taħt ċerti ċirkostanzi, se tħassarek, jekk mhux is-sistema kollha, allura ħafna fajls importanti għall-prestazzjoni tagħha).
[user@testhost ~]$ ls
test test2
[user@testhost ~]$ ls -ltr test2/
total 4
-rw-rw-r-- 1 user user 0 Nov 26 10:40 temp
drwxrwxr-x 2 user user 4096 Nov 26 10:40 temp_dir
[user@testhost ~]$ rm -rf test2
[user@testhost ~]$ ls
test
cp
Ikkopja fajl jew direttorju.
[user@testhost ~]$ ls
temp test
[user@testhost ~]$ cp temp temp_clone
[user@testhost ~]$ ls
temp temp_clone test
Dan il-kmand għandu wkoll għażliet -r и -f, jistgħu jintużaw biex jiżguraw li l-ġerarkija tad-direttorji u l-folders tiġi kkupjata f'post ieħor.
mv
Ċaqlaq jew semmi mill-ġdid fajl jew direttorju.
[user@testhost ~]$ ls -ltr
total 4
drwxrwxr-x 2 user user 4096 Nov 26 10:29 test
-rw-rw-r-- 1 user user 0 Nov 26 10:45 temp
-rw-rw-r-- 1 user user 0 Nov 26 10:46 temp_clone
[user@testhost ~]$ ls test
[user@testhost ~]$ mv test test_renamed
[user@testhost ~]$ mv temp_clone test_renamed/
[user@testhost ~]$ ls
temp test_renamed
[user@testhost ~]$ ls test_renamed/
temp_clone
qattus
Stampa l-kontenut ta' fajl (jew fajls).
[user@testhost ~]$ cat temp
Content of a file.
Lalalala...
Ta 'min ukoll tagħti attenzjoni lill-kmandi ras (output n l-ewwel linji jew bytes tal-fajl) u denb (aktar dwarha aktar tard).
denb
Iġbed n l-aħħar linji jew bytes tal-fajl.
[user@testhost ~]$ tail -1 temp
Lalalala...
L-għażla hija utli ħafna -f — jippermettilek turi dejta ġdida f'fajl f'ħin reali.
inqas
Xi drabi l-fajl tat-test huwa kbir wisq u huwa inkonvenjenti li jurih bil-kmand qattus. Imbagħad tista 'tiftaħ billi tuża l-kmand inqas: il-fajl se joħroġ f'partijiet; in-navigazzjoni f'dawn il-partijiet, it-tfittxija u funzjonalità sempliċi oħra huma disponibbli.
[user@testhost ~]$ less temp
Jista 'wkoll ikun konvenjenti għall-użu inqas bil-conveyor (pajp):
[user@testhost ~]$ grep "ERROR" /tmp/some.log | less
ps
Lista proċessi.
[user@testhost ~]$ ps
PID TTY TIME CMD
761020 pts/2 00:00:00 bash
809720 pts/2 00:00:00 ps
Jien stess normalment nuża l-għażliet BSD "li" - uri l-proċessi kollha fis-sistema (billi jista 'jkun hemm ħafna proċessi, urejt biss l-ewwel 5 minnhom bl-użu tal-pipeline (pajp) u tim ras):
[user@testhost ~]$ ps aux | head -5
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 1 0.0 0.0 19692 2600 ? Ss Jul02 0:10 /sbin/init
root 2 0.0 0.0 0 0 ? S Jul02 0:03 [kthreadd]
root 4 0.0 0.0 0 0 ? I< Jul02 0:00 [kworker/0:0H]
root 6 0.0 0.0 0 0 ? I< Jul02 0:00 [mm_percpu_wq]
Ħafna jużaw ukoll għażliet BSD "axjf", li jippermettilek turi s-siġra tal-proċess (hawnhekk neħħejt parti mill-output għal dimostrazzjoni):
[user@testhost ~]$ ps axjf
PPID PID PGID SID TTY TPGID STAT UID TIME COMMAND
0 2 0 0 ? -1 S 0 0:03 [kthreadd]
2 4 0 0 ? -1 I< 0 0:00 _ [kworker/0:0H]
2 6 0 0 ? -1 I< 0 0:00 _ [mm_percpu_wq]
2 7 0 0 ? -1 S 0 4:08 _ [ksoftirqd/0]
...
...
...
1 4293 4293 4293 tty6 4293 Ss+ 0 0:00 /sbin/mingetty /dev/tty6
1 532967 532964 532964 ? -1 Sl 495 0:00 /opt/td-agent/embedded/bin/ruby /usr/sbin/td-agent --log /var/log/td-agent/td-agent.log --use-v1-config --group td-agent --daemon /var/run/td-agent/td-agent.pid
532967 532970 532964 532964 ? -1 Sl 495 803:06 _ /opt/td-agent/embedded/bin/ruby /usr/sbin/td-agent --log /var/log/td-agent/td-agent.log --use-v1-config --group td-agent --daemon /var/run/td-agent/td-agent.pid
1 537162 533357 532322 ? -1 Sl 0 5067:43 /usr/bin/dockerd --default-ulimit nofile=262144:262144 --dns=172.17.0.1
537162 537177 537177 537177 ? -1 Ssl 0 4649:28 _ docker-containerd --config /var/run/docker/containerd/containerd.toml
537177 537579 537579 537177 ? -1 Sl 0 4:48 | _ docker-containerd-shim -namespace moby -workdir /var/lib/docker/containerd/daemon/io.containerd.runtime.v1.linux/moby/0ee89b20deb3cf08648cd92e1f3e3c661ccffef7a0971
537579 537642 537642 537642 ? -1 Ss 1000 32:11 | | _ /usr/bin/python /usr/bin/supervisord -c /etc/supervisord/api.conf
537642 539764 539764 537642 ? -1 S 1000 0:00 | | _ sh -c echo "READY"; while read -r line; do echo "$line"; supervisorctl shutdown; done
537642 539767 539767 537642 ? -1 S 1000 5:09 | | _ php-fpm: master process (/etc/php73/php-fpm.conf)
539767 783097 539767 537642 ? -1 S 1000 0:00 | | | _ php-fpm: pool test
539767 783131 539767 537642 ? -1 S 1000 0:00 | | | _ php-fpm: pool test
539767 783185 539767 537642 ? -1 S 1000 0:00 | | | _ php-fpm: pool test
...
...
...
Dan il-kmand għandu ħafna għażliet differenti, għalhekk jekk tużah b'mod attiv, nirrakkomanda li taqra d-dokumentazzjoni. Għal ħafna każijiet, huwa biżżejjed li tkun taf biss "ps biex".
joqtlu
Ibgħat sinjal lil proċess. B'mod awtomatiku s-sinjal jintbagħat SINTERMU, li jtemm il-proċess.
[user@testhost ~]$ ps ux
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
531 1027147 0.0 0.0 119956 4260 ? S 14:51 0:00 sshd: user@pts/1
531 1027149 0.0 0.0 115408 3396 pts/1 Ss 14:51 0:00 -bash
531 1027170 0.0 0.0 119956 4136 ? R 14:51 0:00 sshd: user@pts/2
531 1027180 0.0 0.0 115408 3564 pts/2 Ss 14:51 0:00 -bash
531 1033727 0.0 0.0 107960 708 pts/1 S+ 15:17 0:00 sleep 300
531 1033752 0.0 0.0 117264 2604 pts/2 R+ 15:17 0:00 ps ux
[user@testhost ~]$ kill 1033727
[user@testhost ~]$ ps ux
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
531 1027147 0.0 0.0 119956 4260 ? S 14:51 0:00 sshd: user@pts/1
531 1027149 0.0 0.0 115408 3396 pts/1 Ss+ 14:51 0:00 -bash
531 1027170 0.0 0.0 119956 4136 ? R 14:51 0:00 sshd: user@pts/2
531 1027180 0.0 0.0 115408 3564 pts/2 Ss 14:51 0:00 -bash
531 1033808 0.0 0.0 117268 2492 pts/2 R+ 15:17 0:00 ps ux
Peress li proċess jista' jkollu handlers tas-sinjali, joqtlu mhux dejjem iwassal għar-riżultat mistenni - tlestija immedjata tal-proċess. Biex "joqtol" proċess żgur, għandek bżonn tibgħat sinjal lill-proċess SIGKILL. Madankollu, dan jista 'jwassal għal telf ta' data (per eżempju, jekk il-proċess jeħtieġ li jiffrankaw xi informazzjoni fuq disk qabel ma jintemm), għalhekk għandek bżonn tuża dan il-kmand b'kawtela. Numru tas-sinjal SIGKILL - 9, għalhekk il-verżjoni qasira tal-kmand tidher bħal din:
[user@testhost ~]$ ps ux | grep sleep
531 1034930 0.0 0.0 107960 636 pts/1 S+ 15:21 0:00 sleep 300
531 1034953 0.0 0.0 110516 2104 pts/2 S+ 15:21 0:00 grep --color=auto sleep
[user@testhost ~]$ kill -9 1034930
[user@testhost ~]$ ps ux | grep sleep
531 1035004 0.0 0.0 110516 2092 pts/2 S+ 15:22 0:00 grep --color=auto sleep
Minbarra dawk imsemmija SINTERMU и SIGKILL Hemm ħafna aktar sinjali differenti; lista tagħhom tista 'tinstab faċilment fuq l-Internet. U tinsiex li s-sinjali SIGKILL и NEXTSTOP ma jistgħux jiġu interċettati jew injorati.
ping
Ibgħat pakkett ICMP lill-host ECHO_REQUEST.
[user@testhost ~]$ ping google.com
PING google.com (172.217.15.78) 56(84) bytes of data.
64 bytes from iad23s63-in-f14.1e100.net (172.217.15.78): icmp_seq=1 ttl=47 time=1.85 ms
64 bytes from iad23s63-in-f14.1e100.net (172.217.15.78): icmp_seq=2 ttl=47 time=1.48 ms
64 bytes from iad23s63-in-f14.1e100.net (172.217.15.78): icmp_seq=3 ttl=47 time=1.45 ms
64 bytes from iad23s63-in-f14.1e100.net (172.217.15.78): icmp_seq=4 ttl=47 time=1.46 ms
64 bytes from iad23s63-in-f14.1e100.net (172.217.15.78): icmp_seq=5 ttl=47 time=1.45 ms
^C
--- google.com ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4006ms
rtt min/avg/max/mdev = 1.453/1.541/1.850/0.156 ms
Permezz ta 'default ping jaħdem sakemm jintemm manwalment. Għalhekk l-għażla tista' tkun utli -c — in-numru ta' pakketti wara li jintbagħtu ping se tlesti waħdu. Għażla oħra li kultant nuża hija -i, l-intervall bejn il-pakketti li jintbagħtu.
[user@testhost ~]$ ping -c 3 -i 5 google.com
PING google.com (172.217.5.238) 56(84) bytes of data.
64 bytes from iad30s07-in-f238.1e100.net (172.217.5.238): icmp_seq=1 ttl=47 time=1.55 ms
64 bytes from iad30s07-in-f14.1e100.net (172.217.5.238): icmp_seq=2 ttl=47 time=1.17 ms
64 bytes from iad30s07-in-f14.1e100.net (172.217.5.238): icmp_seq=3 ttl=47 time=1.16 ms
--- google.com ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 10006ms
rtt min/avg/max/mdev = 1.162/1.295/1.551/0.181 ms
ssh
Klijent OpenSSH SSH jippermettilek tikkonnettja ma 'host remot.
MacBook-Pro-User:~ user$ ssh [email protected]
Last login: Tue Nov 26 11:27:39 2019 from another_host
[user@testhost ~]$ hostname
testhost
Hemm ħafna sfumaturi fl-użu ta 'SSH, u dan il-klijent għandu wkoll numru kbir ta' kapaċitajiet, għalhekk jekk tixtieq (jew teħtieġ) tista 'taqra dwaru
scp
Ikkopja fajls bejn hosts (għal dan l-użu ssh).
[user@testhost ~]$ pwd
/home/user
[user@testhost ~]$ ls
temp test_renamed
[user@testhost ~]$ exit
logout
Connection to 11.11.22.22 closed.
MacBook-Pro-Aleksandr:~ user$ scp [email protected]:/home/user/temp Downloads/
temp 100% 31 0.2KB/s 00:00
MacBook-Pro-Aleksandr:~ user$ cat Downloads/temp
Content of a file.
Lalalala...
rsync
Tista 'wkoll tuża biex tissinkronizza direttorji bejn hosts rsync (-a — mod arkivju, jippermettilek tikkopja l-kontenut kollu tad-direttorju "kif inhu", -v — output għall-console ta' informazzjoni addizzjonali):
MacBook-Pro-User:~ user$ ls Downloads/user
ls: Downloads/user: No such file or directory
MacBook-Pro-User:~ user$ rsync -av user@testhost:/home/user Downloads
receiving file list ... done
user/
user/.bash_history
user/.bash_logout
user/.bash_profile
user/.bashrc
user/.lesshst
user/.mongorc.js
user/.viminfo
user/1
user/man_signal
user/man_signal_error_log
user/temp
user/.ssh/
user/.ssh/authorized_keys
user/test/
user/test/created_today
user/test/temp_clone
sent 346 bytes received 29210 bytes 11822.40 bytes/sec
total size is 28079 speedup is 0.95
MacBook-Pro-User:~ user$ ls -a Downloads/user
. .bash_history .bash_profile .lesshst .ssh 1 man_signal_error_log test
.. .bash_logout .bashrc .mongorc.js .viminfo man_signal temp
miss
Uri linja ta 'test.
[user@testhost ~]$ echo "Hello"
Hello
Għażliet ta 'min tikkunsidra hawn -n - ma tehmeżx il-linja b'waqfa tal-linja fl-aħħar, u -e — tippermetti l-interpretazzjoni li jaħrab bl-użu ta' "".
[user@testhost ~]$ echo "tHellon"
tHellon
[user@testhost ~]$ echo -n "tHellon"
tHellon[user@testhost ~]$
[user@testhost ~]$ echo -ne "tHellon"
Hello
Tista 'wkoll turi l-valuri tal-varjabbli billi tuża dan il-kmand. Pereżempju, fil-Linux il-kodiċi tal-ħruġ tal-aħħar kmand komplut huwa maħżun f'varjabbli speċjali $?, u b'dan il-mod tista' ssir taf eżattament liema żball seħħ fl-aħħar applikazzjoni li qed taħdem:
[user@testhost ~]$ ls # ошибки не будет
1 man_signal man_signal_error_log temp test
[user@testhost ~]$ echo $? # получим 0 — ошибки не было
0
[user@testhost ~]$ ls qwerty # будет ошибка
ls: cannot access qwerty: No such file or directory
[user@testhost ~]$ echo $? # получим 2 — Misuse of shell builtins (according to Bash documentation)
2
[user@testhost ~]$ echo $? # последний echo отработал без ошибок, получим 0
0
telnet
Klijent għall-protokoll TELNET. Użat biex jikkomunika ma 'host ieħor.
[user@testhost ~]$ telnet example.com 80
Trying 93.184.216.34...
Connected to example.com.
Escape character is '^]'.
GET / HTTP/1.1
Host: example.com
HTTP/1.1 200 OK
Cache-Control: max-age=604800
Content-Type: text/html; charset=UTF-8
Date: Tue, 26 Nov 2019 11:59:18 GMT
Etag: "3147526947+gzip+ident"
Expires: Tue, 03 Dec 2019 11:59:18 GMT
Last-Modified: Thu, 17 Oct 2019 07:18:26 GMT
Server: ECS (dcb/7F3B)
Vary: Accept-Encoding
X-Cache: HIT
Content-Length: 1256
... здесь было тело ответа, которое я вырезал руками ...
Jekk għandek bżonn tuża l-protokoll TLS (ħalluni nfakkarkom li SSL ilu skadut), allura telnet mhux adattat għal dawn l-għanijiet. Imma l-klijent se jiġi OpenSSL:
Eżempju tal-użu ta' openssl bil-ħruġ ta' tweġiba għal talba GET
[user@testhost ~]$ openssl s_client -connect example.com:443
CONNECTED(00000003)
depth=2 C = US, O = DigiCert Inc, OU = www.digicert.com, CN = DigiCert Global Root CA
verify return:1
depth=1 C = US, O = DigiCert Inc, CN = DigiCert SHA2 Secure Server CA
verify return:1
depth=0 C = US, ST = California, L = Los Angeles, O = Internet Corporation for Assigned Names and Numbers, OU = Technology, CN = www.example.org
verify return:1
---
Certificate chain
0 s:/C=US/ST=California/L=Los Angeles/O=Internet Corporation for Assigned Names and Numbers/OU=Technology/CN=www.example.org
i:/C=US/O=DigiCert Inc/CN=DigiCert SHA2 Secure Server CA
1 s:/C=US/O=DigiCert Inc/CN=DigiCert SHA2 Secure Server CA
i:/C=US/O=DigiCert Inc/OU=www.digicert.com/CN=DigiCert Global Root CA
2 s:/C=US/O=DigiCert Inc/OU=www.digicert.com/CN=DigiCert Global Root CA
i:/C=US/O=DigiCert Inc/OU=www.digicert.com/CN=DigiCert Global Root CA
---
Server certificate
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
subject=/C=US/ST=California/L=Los Angeles/O=Internet Corporation for Assigned Names and Numbers/OU=Technology/CN=www.example.org
issuer=/C=US/O=DigiCert Inc/CN=DigiCert SHA2 Secure Server CA
---
No client certificate CA names sent
Peer signing digest: SHA256
Server Temp Key: ECDH, P-256, 256 bits
---
SSL handshake has read 4643 bytes and written 415 bytes
---
New, TLSv1/SSLv3, Cipher is ECDHE-RSA-AES128-GCM-SHA256
Server public key is 2048 bit
Secure Renegotiation IS supported
Compression: NONE
Expansion: NONE
No ALPN negotiated
SSL-Session:
Protocol : TLSv1.2
Cipher : ECDHE-RSA-AES128-GCM-SHA256
Session-ID: 91950DC50FADB57BF026D2661E6CFAA1F522E5CA60D2310E106EE0E0FD6E70BD
Session-ID-ctx:
Master-Key: 704E9145253EEB4E9DC47E3DC6725D296D4A470EA296D54F71D65E74EAC09EB096EA1305CBEDD9E7020B8F72FD2B68A5
Key-Arg : None
Krb5 Principal: None
PSK identity: None
PSK identity hint: None
TLS session ticket lifetime hint: 7200 (seconds)
TLS session ticket:
0000 - 68 84 4e 77 be e3 f5 00-49 c5 44 40 53 4d b9 61 [email protected]
0010 - c9 fe df e4 05 51 d0 53-ae cf 89 4c b6 ef 6c 9e .....Q.S...L..l.
0020 - fe 12 9a f0 e8 e5 4e 87-42 89 ac af ca e5 4a 85 ......N.B.....J.
0030 - 38 08 26 e3 22 89 08 b5-62 c0 8b 7e b8 05 d3 54 8.&."...b..~...T
0040 - 8c 24 91 a7 b4 4f 79 ad-36 59 7c 69 2d e5 7f 62 .$...Oy.6Y|i-..b
0050 - f6 73 a3 8b 92 63 c1 e3-df 78 ba 8c 5a cc 82 50 .s...c...x..Z..P
0060 - 33 4e 13 4b 10 e4 97 31-cc b4 13 65 45 60 3e 13 3N.K...1...eE`>.
0070 - ac 9e b1 bb 4b 18 d9 16-ea ce f0 9b 5b 0c 8b bf ....K.......[...
0080 - fd 78 74 a0 1a ef c2 15-2a 0a 14 8d d1 3f 52 7a .xt.....*....?Rz
0090 - 12 6b c7 81 15 c4 c4 af-7e df c2 20 a8 dd 4b 93 .k......~.. ..K.
Start Time: 1574769867
Timeout : 300 (sec)
Verify return code: 0 (ok)
---
GET / HTTP/1.1
Host: example.com
HTTP/1.1 200 OK
Cache-Control: max-age=604800
Content-Type: text/html; charset=UTF-8
Date: Tue, 26 Nov 2019 12:04:38 GMT
Etag: "3147526947+ident"
Expires: Tue, 03 Dec 2019 12:04:38 GMT
Last-Modified: Thu, 17 Oct 2019 07:18:26 GMT
Server: ECS (dcb/7EC8)
Vary: Accept-Encoding
X-Cache: HIT
Content-Length: 1256
<!doctype html>
<html>
<head>
<title>Example Domain</title>
<meta charset="utf-8" />
<meta http-equiv="Content-type" content="text/html; charset=utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1" />
<style type="text/css">
body {
background-color: #f0f0f2;
margin: 0;
padding: 0;
font-family: -apple-system, system-ui, BlinkMacSystemFont, "Segoe UI", "Open Sans", "Helvetica Neue", Helvetica, Arial, sans-serif;
}
div {
width: 600px;
margin: 5em auto;
padding: 2em;
background-color: #fdfdff;
border-radius: 0.5em;
box-shadow: 2px 3px 7px 2px rgba(0,0,0,0.02);
}
a:link, a:visited {
color: #38488f;
text-decoration: none;
}
@media (max-width: 700px) {
div {
margin: 0 auto;
width: auto;
}
}
</style>
</head>
<body>
<div>
<h1>Example Domain</h1>
<p>This domain is for use in illustrative examples in documents. You may use this
domain in literature without prior coordination or asking for permission.</p>
<p><a href="https://www.iana.org/domains/example">More information...</a></p>
</div>
</body>
</html>
Issolvi problemi komuni fil-Linux
Ibdel is-sid tal-fajl
Tista 'tbiddel is-sid ta' fajl jew direttorju billi tuża l-kmand chown:
[user@testhost ~]$ chown user:user temp
[user@testhost ~]$ ls -l temp
-rw-rw-r-- 1 user user 31 Nov 26 11:09 temp
Il-parametru għal dan il-kmand għandu jingħata s-sid il-ġdid u l-grupp (mhux obbligatorju), separati b'kolon. Ukoll, meta tbiddel is-sid ta 'direttorju, l-għażla tista' tkun utli -R - imbagħad is-sidien se jinbidlu għall-kontenut kollu tad-direttorju.
Ibdel il-permessi tal-fajls
Din il-problema tista 'tiġi solvuta bl-użu tal-kmand chmod. Bħala eżempju, se nagħti l-issettjar tal-permess "is-sid huwa permess jaqra, jikteb u jesegwixxi, il-grupp jitħalla jaqra u jikteb, kulħadd jitħalla xejn":
[user@testhost ~]$ ls -l temp
-rw-rw-r-- 1 user user 31 Nov 26 11:09 temp
[user@testhost ~]$ chmod 760 temp
[user@testhost ~]$ ls -l temp
-rwxrw---- 1 user user 31 Nov 26 11:09 temp
L-ewwel 7 (dan huwa 0b111 fir-rappreżentazzjoni tal-bit) fil-parametru tfisser "id-drittijiet kollha għas-sid", it-tieni 6 (dan huwa 0b110 fir-rappreżentazzjoni tal-bit) tfisser "aqra u tikteb", u 0 tfisser xejn għall-bqija . Bitmask jikkonsisti fi tliet bits: il-bit l-inqas sinifikanti ("lemin") huwa responsabbli għall-eżekuzzjoni, il-bit li jmiss ("nofs") huwa għall-kitba, u l-aktar bit sinifikanti ("xellug") huwa għall-qari.
Tista' wkoll tissettja permessi billi tuża karattri speċjali (sintassi mnemonika). Pereżempju, l-eżempju li ġej l-ewwel ineħħi d-drittijiet ta’ eżekuzzjoni għall-utent attwali u mbagħad jibdelhom lura:
[user@testhost ~]$ ls -l temp
-rwxrw---- 1 user user 31 Nov 26 11:09 temp
[user@testhost ~]$ chmod -x temp
[user@testhost ~]$ ls -l temp
-rw-rw---- 1 user user 31 Nov 26 11:09 temp
[user@testhost ~]$ chmod +x temp
[user@testhost ~]$ ls -l temp
-rwxrwx--x 1 user user 31 Nov 26 11:09 temp
Dan il-kmand għandu ħafna użi, għalhekk nagħtik parir biex taqra aktar dwaru (speċjalment dwar is-sintassi mnemonika, pereżempju,
Stampa l-kontenut ta 'fajl binarju
Dan jista 'jsir bl-użu ta' l-utilità hexdump. Hawn taħt hemm eżempji tal-użu tiegħu.
[user@testhost ~]$ cat temp
Content of a file.
Lalalala...
[user@testhost ~]$ hexdump -c temp
0000000 C o n t e n t o f a f i l
0000010 e . n L a l a l a l a . . . n
000001f
[user@testhost ~]$ hexdump -x temp
0000000 6f43 746e 6e65 2074 666f 6120 6620 6c69
0000010 2e65 4c0a 6c61 6c61 6c61 2e61 2e2e 000a
000001f
[user@testhost ~]$ hexdump -C temp
00000000 43 6f 6e 74 65 6e 74 20 6f 66 20 61 20 66 69 6c |Content of a fil|
00000010 65 2e 0a 4c 61 6c 61 6c 61 6c 61 2e 2e 2e 0a |e..Lalalala....|
0000001f
Permezz ta 'din l-utilità, tista' toħroġ data f'formati oħra, iżda dawn huma l-aktar għażliet utli ħafna biex tużaha.
Fittex fajls
Tista' ssib fajl b'parti minn ismu fis-siġra tad-direttorju billi tuża l-kmand isibu:
[user@testhost ~]$ find test_dir/ -name "*le*"
test_dir/file_1
test_dir/file_2
test_dir/subdir/file_3
Għażliet oħra ta' tfittxija u filtri huma wkoll disponibbli. Per eżempju, dan huwa kif tista 'ssib fajls f'folder testmaħluqa aktar minn 5 ijiem ilu:
[user@testhost ~]$ ls -ltr test
total 0
-rw-rw-r-- 1 user user 0 Nov 26 10:46 temp_clone
-rw-rw-r-- 1 user user 0 Dec 4 10:39 created_today
[user@testhost ~]$ find test/ -type f -ctime +5
test/temp_clone
Fittex it-test fil-fajls
It-tim jgħinek tlaħħaq ma 'dan il-kompitu grep. Għandu ħafna użi, l-aktar wieħed sempliċi huwa mogħti hawn bħala eżempju.
[user@testhost ~]$ grep -nr "content" test_dir/
test_dir/file_1:1:test content for file_1
test_dir/file_2:1:test content for file_2
test_dir/subdir/file_3:1:test content for file_3
Wieħed mill-modi popolari biex tuża l-kmand grep - tużah f'pipeline (pajp):
[user@testhost ~]$ sudo tail -f /var/log/test.log | grep "ERROR"
Għażla -v jippermettilek tagħmel effett grep'u l-maqlub - linji biss li ma fihomx il-mudell mgħoddi grep.
Ara l-pakketti installati
M'hemm l-ebda kmand universali, għax kollox jiddependi fuq id-distribuzzjoni tal-Linux u l-maniġer tal-pakkett użat. X'aktarx li wieħed mill-kmandi li ġejjin jgħinek:
yum list installed
apt list --installed
zypper se —installed-only
pacman -Qqe
dpkg -l
rpm -qa
Ara kemm tieħu spazju s-siġra tad-direttorju
Waħda mill-għażliet għall-użu tal-kmand du:
[user@testhost ~]$ du -h -d 1 test_dir/
8,0K test_dir/subdir
20K test_dir/
Tista 'tbiddel il-valur tal-parametru -dbiex tikseb aktar informazzjoni dettaljata dwar is-siġra tad-direttorju. Tista 'wkoll tuża l-kmand flimkien ma' tip:
[user@testhost ~]$ du -h -d 1 test_dir/ | sort -h
8,0K test_dir/subdir
16K test_dir/subdir_2
36K test_dir/
[user@testhost ~]$ du -h -d 1 test_dir/ | sort -h -r
36K test_dir/
16K test_dir/subdir_2
8,0K test_dir/subdir
Għażla -h it-tim tip jippermettilek issortja daqsijiet miktuba f'format li jinqara mill-bniedem (per eżempju, 1K, 2G), għażla -r jippermettilek issortja d-data f'ordni inversa.
"Sib u ibdel" f'fajl, f'fajls f'direttorju
Din l-operazzjoni titwettaq bl-użu tal-utilità għatx (l-ebda bandiera g fl-aħħar, l-ewwel okkorrenza biss ta '"test antik" fil-linja se tiġi sostitwita):
sed -i 's/old-text/new-text/g' input.txt
Tista' tużah għal diversi fajls f'daqqa:
[user@testhost ~]$ cat test_dir/file_*
test content for file_1
test content for file_2
[user@testhost ~]$ sed -i 's/test/edited/g' test_dir/file_*
[user@testhost ~]$ cat test_dir/file_*
edited content for file_1
edited content for file_2
Iġbed kolonna mill-output
Se jgħin biex ilaħħaq ma 'dan il-kompitu naqra. Dan l-eżempju juri t-tieni kolonna tal-output tal-kmand `ps ux`:
[user@testhost ~]$ ps ux | awk '{print $2}'
PID
11023
25870
25871
25908
25909
Fl-istess ħin, wieħed irid iżomm f'moħħu li naqra għandha funzjonalità ħafna aktar sinjuri, għalhekk jekk għandek bżonn taħdem b'test fuq il-linja tal-kmand, għandek taqra aktar dwar dan il-kmand.
Sib l-indirizz IP mill-hostname
Wieħed mill-kmandi li ġejjin se jgħin f'dan:
[user@testhost ~]$ host ya.ru
ya.ru has address 87.250.250.242
ya.ru has IPv6 address 2a02:6b8::2:242
ya.ru mail is handled by 10 mx.yandex.ru.
[user@testhost ~]$ dig +short ya.ru
87.250.250.242
[user@testhost ~]$ nslookup ya.ru
Server: 8.8.8.8
Address: 8.8.8.8#53
Non-authoritative answer:
Name: ya.ru
Address: 87.250.250.242
Informazzjoni tan-Netwerk
Jista 'juża ifconfig:
[user@testhost ~]$ ifconfig
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 47.89.93.67 netmask 255.255.224.0 broadcast 47.89.95.255
inet6 fd90::302:57ff:fe79:1 prefixlen 64 scopeid 0x20<link>
ether 04:01:57:79:00:01 txqueuelen 1000 (Ethernet)
RX packets 11912135 bytes 9307046034 (8.6 GiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 14696632 bytes 2809191835 (2.6 GiB)
TX errors 0 dropped 0 overruns 0 carrier 0 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 0 (Local Loopback)
RX packets 10 bytes 866 (866.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 10 bytes 866 (866.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
Jew forsi ip:
[user@testhost ~]$ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 04:01:57:79:00:01 brd ff:ff:ff:ff:ff:ff
inet 47.89.93.67/19 brd 47.89.95.255 scope global eth0
valid_lft forever preferred_lft forever
inet6 fd90::302:57ff:fe79:1/64 scope link
valid_lft forever preferred_lft forever
3: ip_vti0: <NOARP> mtu 1500 qdisc noop state DOWN group default
link/ipip 0.0.0.0 brd 0.0.0.0
Barra minn hekk, jekk, pereżempju, inti interessat biss fl-IPv4, allura tista 'żżid l-għażla -4:
[user@testhost ~]$ ip -4 a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
inet 47.89.93.67/19 brd 47.89.95.255 scope global eth0
valid_lft forever preferred_lft forever
Ara portijiet miftuħa
Biex tagħmel dan, uża l-utilità netstat. Pereżempju, biex tara l-portijiet tas-smigħ TCP u UDP kollha b'wiri tal-PID tal-proċess li jisma' fuq il-port u rappreżentazzjoni numerika tal-port, għandek bżonn tużaha bl-għażliet li ġejjin:
[user@testhost ~]$ netstat -lptnu
Informazzjoni tas-Sistema
Tista 'tikseb din l-informazzjoni billi tuża l-kmand uname.
[user@testhost ~]$ uname -a
Linux alexander 3.10.0-123.8.1.el7.x86_64 #1 SMP Mon Sep 22 19:06:58 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
Biex tifhem il-format li fih tiġi prodotta l-output, tista 'tirreferi għal jgħinu'għal dan il-kmand:
[user@testhost ~]$ uname --help
Использование: uname [КЛЮЧ]…
Печатает определенные сведения о системе. Если КЛЮЧ не задан,
подразумевается -s.
-a, --all напечатать всю информацию, в следующем порядке,
кроме -p и -i, если они неизвестны:
-s, --kernel-name напечатать имя ядра
-n, --nodename напечатать имя машины в сети
-r, --release напечатать номер выпуска операционной системы
-v, --kernel-version напечатать версию ядра
-m, --machine напечатать тип оборудования машины
-p, --processor напечатать тип процессора или «неизвестно»
-i, --hardware-platform напечатать тип аппаратной платформы или «неизвестно»
-o, --operating-system напечатать имя операционной системы
--help показать эту справку и выйти
--version показать информацию о версии и выйти
Informazzjoni dwar il-memorja
Biex tifhem kemm RAM hija okkupata jew ħielsa, tista 'tuża l-kmand ħielsa.
[user@testhost ~]$ free -h
total used free shared buff/cache available
Mem: 3,9G 555M 143M 56M 3,2G 3,0G
Swap: 0B 0B 0B
Informazzjoni dwar is-sistemi tal-fajls (spazju ħieles fuq id-diska)
Team df jippermettilek tara kemm spazju huwa ħieles u okkupat fuq sistemi ta 'fajls immuntati.
[user@testhost ~]$ df -hT
Файловая система Тип Размер Использовано Дост Использовано% Cмонтировано в
/dev/vda1 ext4 79G 21G 55G 27% /
devtmpfs devtmpfs 2,0G 0 2,0G 0% /dev
tmpfs tmpfs 2,0G 0 2,0G 0% /dev/shm
tmpfs tmpfs 2,0G 57M 1,9G 3% /run
tmpfs tmpfs 2,0G 0 2,0G 0% /sys/fs/cgroup
tmpfs tmpfs 396M 0 396M 0% /run/user/1001
Għażla -T jispeċifika li t-tip tas-sistema tal-fajls għandu jiġi dedott.
Informazzjoni dwar kompiti u statistika varji fuq is-sistema
Biex tagħmel dan, uża l-kmand quċċata. Huwa kapaċi juri diversi informazzjoni: pereżempju, l-ogħla proċessi bl-użu tar-RAM jew l-ogħla proċessi skont l-użu tal-ħin tas-CPU. Turi wkoll informazzjoni dwar il-memorja, CPU, uptime u LA (medja tat-tagħbija).
[user@testhost ~]$ top | head -10
top - 17:19:13 up 154 days, 6:59, 3 users, load average: 0.21, 0.21, 0.27
Tasks: 2169 total, 2 running, 2080 sleeping, 0 stopped, 0 zombie
Cpu(s): 1.7%us, 0.7%sy, 0.0%ni, 97.5%id, 0.0%wa, 0.0%hi, 0.1%si, 0.0%st
Mem: 125889960k total, 82423048k used, 43466912k free, 16026020k buffers
Swap: 0k total, 0k used, 0k free, 31094516k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
25282 user 20 0 16988 3936 1964 R 7.3 0.0 0:00.04 top
4264 telegraf 20 0 2740m 240m 22m S 1.8 0.2 23409:39 telegraf
6718 root 20 0 35404 4768 3024 S 1.8 0.0 0:01.49 redis-server
Din l-utilità għandha funzjonalità rikka, għalhekk jekk għandek bżonn tużaha spiss, huwa aħjar li taqra d-dokumentazzjoni tagħha.
Dump tat-traffiku tan-netwerk
Biex tinterċetta t-traffiku tan-netwerk fil-Linux, tintuża utilità tcpdump. Biex titfa 'traffiku fuq il-port 12345, tista' tuża l-kmand li ġej:
[user@testhost ~]$ sudo tcpdump -i any -A port 12345
Għażla -A jgħid li rridu naraw l-output f'ASCII (għalhekk huwa tajjeb għall-protokolli tat-test), -i kwalunkwe jindika li m'aħniex interessati fl-interface tan-netwerk, port — liema traffiku tal-port għandu jintrema. Minflok port tista 'tuża ospitanti, jew kombinazzjoni ospitanti и port (ospitanti A u port X). Għażla oħra utli tista 'tkun -n — tikkonvertix l-indirizzi għal hostnames fl-output.
X'jiġri jekk it-traffiku huwa binarju? Imbagħad l-għażla tgħinna -X — dejta tal-ħruġ f'hex u ASCII:
[user@testhost ~]$ sudo tcpdump -i any -X port 12345
Għandu jittieħed kont li fiż-żewġ każijiet ta 'użu se joħorġu pakketti IP, għalhekk fil-bidu ta' kull wieħed minnhom se jkun hemm headers binarji IP u TCP. Hawnhekk hawn eżempju output għall-mistoqsija "123" mibgħuta lis-server jisma fuq il-port 12345:
[user@testhost ~]$ sudo tcpdump -i any -X port 12345
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on any, link-type LINUX_SLL (Linux cooked), capture size 262144 bytes
14:27:13.224762 IP localhost.49794 > localhost.italk: Flags [P.], seq 2262177478:2262177483, ack 3317210845, win 342, options [nop,nop,TS val 3196604972 ecr 3196590131], length 5
0x0000: 4510 0039 dfb6 4000 4006 5cf6 7f00 0001 E..9..@.@......
0x0010: 7f00 0001 c282 3039 86d6 16c6 c5b8 9edd ......09........
0x0020: 8018 0156 fe2d 0000 0101 080a be88 522c ...V.-........R,
0x0030: be88 1833 3132 330d 0a00 0000 0000 0000 ...3123.........
0x0040: 0000 0000 0000 0000 00 .........
Minflok output
Naturalment, hemm ħafna aktar affarijiet interessanti fil-Linux li tista’ taqra dwarhom fuq Habré, StackOverflow u siti oħra (nagħtik eżempju
Sors: www.habr.com