foreword
Halo sadayana! Nami abdi Sasha, sareng kuring parantos nguji backend (jasa Linux sareng API) langkung ti genep taun. Gagasan pikeun tulisan éta sumping ka kuring saatos pamenta anu sanés ti babaturan panguji pikeun nyarioskeun naon anu anjeunna tiasa maca ngeunaan paréntah Linux sateuacan wawancara. Biasana, calon pikeun posisi insinyur QA diwajibkeun terang paréntah dasar (upami, tangtosna, aranjeunna ngalibatkeun gawé bareng Linux), tapi kumaha anjeun terang paréntah mana anu patut dibaca nalika nyiapkeun wawancara upami anjeun gaduh sakedik. atanapi henteu gaduh pangalaman sareng Linux?
Ku alatan éta, sanajan ieu geus ditulis ngeunaan sababaraha kali, kuring masih mutuskeun pikeun nulis artikel sejen "Linux for beginners" jeung daptar di dieu paréntah dasar nu peryogi kauninga saméméh sagala wawancara di departemen (atawa parusahaan) anu ngagunakeun Linux Ubuntu. Kuring mikir ngeunaan paréntah sareng utilitas sareng parameter mana anu kuring sering dianggo, ngumpulkeun tanggapan ti kolega kuring, sareng disusun sadayana kana hiji tulisan. Artikel ieu dibagi jadi 3 bagian: kahiji, informasi ringkes ngeunaan dasar I/O di terminal Linux Ubuntu, lajeng tinjauan paréntah paling dasar, jeung bagian katilu ngajelaskeun kumaha carana ngajawab masalah umum dina Linux.
Unggal paréntah ngagaduhan seueur pilihan, sadayana moal didaptarkeun di dieu. Anjeun salawasna bisa ngasupkeun `lalaki <paréntah>`atawa`<paréntah> --pitulung` pikeun leuwih jéntré ngeunaan tim.
contona:
[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'
Upami paréntahna panjang teuing pikeun réngsé, anjeun tiasa ngeureunkeunana ku ngaklik dina konsol Ctrl + C (sinyal dikirim ka prosés TANDA).
A saeutik ngeunaan kaluaran paréntah
Nalika prosés dimimitian dina Linux, 3 aliran data standar diciptakeun pikeun prosés éta: stdin, stdout и stderr. Aranjeunna wilanganana 0, 1 sareng 2 masing-masing. Tapi ayeuna urang museurkeun stdout jeung, ka extent Lesser, stderr. Tina ngaran éta gampang ditebak éta stdout dipaké pikeun kaluaran data, jeung stderr — pikeun mintonkeun talatah kasalahan. Sacara standar nalika ngajalankeun paréntah dina Linux stdout и stderr kaluaran sagala informasi ka konsol, kumaha oge, lamun kaluaran paréntah badag, meureun nya merenah pikeun alihan ka file. Ieu tiasa dilakukeun, contona, sapertos kieu:
[user@testhost ~]$ man signal > man_signal
Lamun urang kaluaran eusi file man_signal, mangka urang bakal nempo yén éta téh idéntik jeung naon bakal lamun urang ngan ngajalankeun paréntah `sinyal lalaki`.
Operasi alihan `>` ingkar kana stdout. Anjeun tiasa nangtukeun alihan stdout sacara eksplisit: `1>`. Nya kitu, Anjeun bisa nangtukeun redirection stderr:`2>`. Anjeun tiasa ngagabungkeun operasi ieu sahingga misahkeun kaluaran paréntah normal sareng kaluaran pesen kasalahan:
[user@testhost ~]$ man signal 1> man_signal 2> man_signal_error_log
Alihan jeung stdoutjeung stderr kana hiji file saperti kieu:
[user@testhost ~]$ man signal > man_signal 2>&1
Operasi alihan `2> & 1` hartina alihan stderr ka tempat anu sarua sakumaha diarahkeun stdout.
alat sejen merenah pikeun gawé bareng I / O (atawa rada, éta alat merenah pikeun komunikasi interprocess) nyaeta pipah (atawa conveyor). Pipelines sering dianggo pikeun komunikasi sababaraha paréntah: stdout paréntah dialihkeun ka stdin salajengna, jeung saterusna dina ranté:
[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
Paréntah Linux Ubuntu Dasar
pwd
Témbongkeun diréktori ayeuna (jalan).
[user@testhost ~]$ pwd
/home/user
kaping
Pintonan tanggal sareng waktos sistem ayeuna.
[user@testhost ~]$ date
Mon Dec 16 13:37:07 UTC 2019
[user@testhost ~]$ date +%s
1576503430
w
Paréntah ieu nunjukkeun saha anu asup kana sistem. Salaku tambahan, uptime sareng LA (rata-rata beban) ogé ditampilkeun dina layar.
[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
Nyitak eusi diréktori. Lamun anjeun teu lulus jalur, eusi diréktori ayeuna bakal dipintonkeun.
[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
Pribadi, kuring sering nganggo pilihan -l (Format daptar panjang - kaluaran kana kolom sareng inpormasi tambahan ngeunaan file), -t (asihan ku file / waktos modifikasi diréktori) jeung -r (asihan sabalikna - dina kombinasi sareng -t file panganyarna bakal aya di handap):
[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
Aya 2 ngaran diréktori husus: "."Jeung"..". Anu kahiji hartina diréktori ayeuna, anu kadua hartina diréktori indungna. Éta tiasa merenah dianggo dina sababaraha tim, khususna 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
Aya ogé pilihan anu kapaké pikeun nampilkeun file anu disumputkeun (dimimitian ku ".")- -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
Anjeun oge bisa make pilihan -h - kaluaran dina format anu tiasa dibaca manusa (perhatikeun ukuran file):
[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
Robah diréktori ayeuna.
[user@testhost ~]$ pwd
/home/user
[user@testhost ~]$ cd /home/
[user@testhost home]$ pwd
/home
Upami anjeun henteu ngalangkungan nami diréktori salaku argumen, variabel lingkungan bakal dianggo $ RUMAH, nyaeta, diréktori imah. Ogé bisa jadi merenah ngagunakeun `~` nyaéta harti karakter husus $ RUMAH:
[user@testhost etc]$ pwd
/etc
[user@testhost etc]$ cd ~/test/
[user@testhost test]$ pwd
/home/user/test
mkdir
Jieun diréktori.
[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
Kadang-kadang anjeun kedah nyiptakeun struktur diréktori khusus: contona, diréktori dina diréktori anu henteu aya. Pikeun ngahindarkeun ngasupkeun sababaraha kali dina urutan mkdir, anjeun tiasa nganggo pilihan -p — ngamungkinkeun anjeun nyiptakeun sadaya diréktori anu leungit dina hierarki. Ogé kalawan pilihan ieu mkdir moal balik kasalahan lamun diréktori aya.
[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
Pupus file.
[user@testhost ~]$ ls
qqq test test2
[user@testhost ~]$ rm qqq
[user@testhost ~]$ ls
test test2
Pilihan -r ngidinan Anjeun pikeun recursively ngahapus directories kalawan sakabeh eusina, pilihan -f ngidinan Anjeun pikeun malire kasalahan nalika ngahapus (contona, ngeunaan file non-existent). Pilihan ieu ngamungkinkeun, kasarna nyarios, ngahapus ngajamin sadaya hierarki file sareng diréktori (upami pangguna ngagaduhan hak pikeun ngalakukeunana), janten, aranjeunna kedah dianggo kalayan ati-ati (conto guyonan klasik nyaéta "rm-rf /", dina kaayaan anu tangtu, bakal ngahapus anjeun, upami henteu sadayana sistem, maka seueur file anu penting pikeun pagelaranana).
[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
Nyalin file atawa diréktori.
[user@testhost ~]$ ls
temp test
[user@testhost ~]$ cp temp temp_clone
[user@testhost ~]$ ls
temp temp_clone test
Paréntah ieu ogé ngagaduhan pilihan -r и -f, aranjeunna tiasa dianggo pikeun mastikeun yén hierarki diréktori sareng polder disalin ka lokasi anu sanés.
mv
Pindahkeun atanapi ganti nami file atanapi diréktori.
[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
ucing
Nyitak eusi file (atawa file).
[user@testhost ~]$ cat temp
Content of a file.
Lalalala...
Éta ogé patut nengetan paréntah sirah (kaluaran n garis kahiji atawa bait file) jeung buntut (langkung seueur ngeunaan anjeunna engké).
buntut
Mundur n garis panungtungan atawa bait file.
[user@testhost ~]$ tail -1 temp
Lalalala...
pilihan pisan mangpaat -f — éta ngamungkinkeun anjeun pikeun ningalikeun data énggal dina file sacara real waktos.
leuwih saeutik
Kadang-kadang file téks ageung teuing sareng henteu pikaresepeun pikeun nampilkeunana nganggo paréntah ucing. Teras anjeun tiasa mukakeunana nganggo paréntah leuwih saeutik: file bakal kaluaran sabagian; navigasi ngaliwatan bagian-bagian ieu, milarian sareng fungsionalitas saderhana sanésna sayogi.
[user@testhost ~]$ less temp
Ogé bisa jadi merenah ngagunakeun leuwih saeutik kalawan conveyor (pipah):
[user@testhost ~]$ grep "ERROR" /tmp/some.log | less
ps
Daptar prosés.
[user@testhost ~]$ ps
PID TTY TIME CMD
761020 pts/2 00:00:00 bash
809720 pts/2 00:00:00 ps
Kuring sorangan biasana ngagunakeun pilihan BSD "aux"- mintonkeun sadaya prosés dina sistem (kusabab aya seueur prosés, kuring ngan ukur ningalikeun 5 anu munggaran nganggo jalur pipa (pipah) jeung tim sirah):
[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]
Seueur ogé anu nganggo pilihan BSD "axjf", anu ngamungkinkeun anjeun pikeun nampilkeun tangkal prosés (di dieu kuring ngaleungitkeun bagian tina kaluaran pikeun démo):
[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 "$line"; supervisorctl shutdown; done
537642 539767 539767 537642 ? -1 S 1000 5:09 | | _ php-fpm: master process (/etc/php73/php-fpm.conf)
539767 783097 539767 537642 ? -1 S 1000 0:00 | | | _ php-fpm: pool test
539767 783131 539767 537642 ? -1 S 1000 0:00 | | | _ php-fpm: pool test
539767 783185 539767 537642 ? -1 S 1000 0:00 | | | _ php-fpm: pool test
...
...
...
Paréntah ieu ngagaduhan seueur pilihan anu béda, janten upami anjeun aktip ngagunakeunana, kuring nyarankeun yén anjeun maca dokuméntasi. Kanggo sabagéan ageung kasus, cukup ngan ukur terang "ps nuju".
maehan
Kirim sinyal ka prosés. Sacara standar sinyal dikirimkeun TANDA, nu terminates prosés.
[user@testhost ~]$ 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
Kusabab prosés tiasa gaduh panangan sinyal, maehan teu salawasna ngakibatkeun hasil ekspektasi - parantosan instan prosés. Pikeun "maéhan" prosés pasti, anjeun kedah ngirim sinyal kana prosés éta SIGKILL. Nanging, ieu tiasa nyababkeun leungitna data (contona, upami prosésna kedah nyimpen sababaraha inpormasi ka disk sateuacan ngeureunkeun), janten anjeun kedah nganggo paréntah ieu kalayan ati-ati. Nomer sinyal SIGKILL - 9, janten versi pondok paréntah sapertos kieu:
[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
Salian ti nu disebutkeun TANDA и SIGKILL Aya seueur deui sinyal anu béda; daptar di antarana tiasa gampang dipendakan dina Internét. Sarta ulah poho yén sinyal SIGKILL и NEXTSTOP teu bisa dicegat atawa dipaliré.
ping
Kirim hiji pakét ICMP ka 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
sacara standar ping jalan dugi ka terminated sacara manual. Kituna pilihan bisa jadi mangpaat -c - Jumlah pakét sanggeus dikirim ping bakal ngalengkepan sorangan. pilihan séjén I kadang ngagunakeun nyaeta -i, interval antara ngirim pakét.
[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
OpenSSH SSH klien ngidinan Anjeun pikeun nyambung ka host jauh.
MacBook-Pro-User:~ user$ ssh [email protected]
Last login: Tue Nov 26 11:27:39 2019 from another_host
[user@testhost ~]$ hostname
testhost
Aya seueur nuansa dina ngagunakeun SSH, sareng klien ieu ogé ngagaduhan seueur kamampuan, janten upami anjeun hoyong (atanapi peryogi) anjeun tiasa maca ngeunaan éta. .
scp
Nyalin file antara host (pikeun panggunaan ieu 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
Anjeun oge bisa make pikeun nyingkronkeun directories antara host rsync (-a - mode arsip, ngidinan Anjeun pikeun nyalin sakabéh eusi diréktori "sakumaha aya", -v - kaluaran kana konsol inpormasi tambahan):
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
gema
Témbongkeun garis téks.
[user@testhost ~]$ echo "Hello"
Hello
Pilihan anu patut dipertimbangkeun di dieu -n - ulah append garis kalawan putus garis dina tungtungna, jeung -e - aktipkeun interpretasi lolos nganggo "".
[user@testhost ~]$ echo "tHellon"
tHellon
[user@testhost ~]$ echo -n "tHellon"
tHellon[user@testhost ~]$
[user@testhost ~]$ echo -ne "tHellon"
Hello
Anjeun ogé tiasa ningalikeun nilai variabel nganggo paréntah ieu. Contona, dina Linux Ubuntu kode kaluar tina paréntah réngsé panungtungan disimpen dina variabel husus $?, sareng ku cara ieu anjeun tiasa terang naon kasalahan anu lumangsung dina aplikasi anu terakhir jalan:
[user@testhost ~]$ 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 $? # последний echo отработал без ошибок, получим 0
0
telnet
Klién pikeun protokol TELNET. Dipaké pikeun komunikasi sareng host sejen.
[user@testhost ~]$ 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 ...
Upami anjeun kedah nganggo protokol TLS (hayu kuring ngingetan yén SSL parantos lami lami), teras telnet teu cocog pikeun tujuan ieu. Tapi klien bakal datang openssl:
Conto ngagunakeun openssl kalayan ngaluarkeun réspon kana pamundut 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 .$...Oy.6Y|i-..b
0050 - f6 73 a3 8b 92 63 c1 e3-df 78 ba 8c 5a cc 82 50 .s...c...x..Z..P
0060 - 33 4e 13 4b 10 e4 97 31-cc b4 13 65 45 60 3e 13 3N.K...1...eE`>.
0070 - ac 9e b1 bb 4b 18 d9 16-ea ce f0 9b 5b 0c 8b bf ....K.......[...
0080 - fd 78 74 a0 1a ef c2 15-2a 0a 14 8d d1 3f 52 7a .xt.....*....?Rz
0090 - 12 6b c7 81 15 c4 c4 af-7e df c2 20 a8 dd 4b 93 .k......~.. ..K.
Start Time: 1574769867
Timeout : 300 (sec)
Verify return code: 0 (ok)
---
GET / HTTP/1.1
Host: example.com
HTTP/1.1 200 OK
Cache-Control: max-age=604800
Content-Type: text/html; charset=UTF-8
Date: Tue, 26 Nov 2019 12:04:38 GMT
Etag: "3147526947+ident"
Expires: Tue, 03 Dec 2019 12:04:38 GMT
Last-Modified: Thu, 17 Oct 2019 07:18:26 GMT
Server: ECS (dcb/7EC8)
Vary: Accept-Encoding
X-Cache: HIT
Content-Length: 1256
<!doctype html>
<html>
<head>
<title>Example Domain</title>
<meta charset="utf-8" />
<meta http-equiv="Content-type" content="text/html; charset=utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1" />
<style type="text/css">
body {
background-color: #f0f0f2;
margin: 0;
padding: 0;
font-family: -apple-system, system-ui, BlinkMacSystemFont, "Segoe UI", "Open Sans", "Helvetica Neue", Helvetica, Arial, sans-serif;
}
div {
width: 600px;
margin: 5em auto;
padding: 2em;
background-color: #fdfdff;
border-radius: 0.5em;
box-shadow: 2px 3px 7px 2px rgba(0,0,0,0.02);
}
a:link, a:visited {
color: #38488f;
text-decoration: none;
}
@media (max-width: 700px) {
div {
margin: 0 auto;
width: auto;
}
}
</style>
</head>
<body>
<div>
<h1>Example Domain</h1>
<p>This domain is for use in illustrative examples in documents. You may use this
domain in literature without prior coordination or asking for permission.</p>
<p><a href="https://www.iana.org/domains/example">More information...</a></p>
</div>
</body>
</html>
Ngarengsekeun masalah umum dina Linux
Robah pamilik file
Anjeun tiasa ngarobih nu gaduh file atanapi diréktori nganggo paréntah kalangkang:
[user@testhost ~]$ chown user:user temp
[user@testhost ~]$ ls -l temp
-rw-rw-r-- 1 user user 31 Nov 26 11:09 temp
Parameter pikeun paréntah ieu kedah dipasihan juragan sareng grup énggal (opsional), dipisahkeun ku titik dua. Ogé, nalika ngarobih nu gaduh diréktori, pilihan éta tiasa mangpaat -R - lajeng nu boga bakal robah pikeun sakabéh eusi diréktori nu.
Robah idin file
Masalah ieu tiasa direngsekeun nganggo paréntah chmod. Salaku conto, kuring bakal masihan setélan idin "nu gaduh diidinan maca, nyerat sareng ngaéksekusi, grup diidinan maca sareng nyerat, sadayana anu sanés diidinan nanaon":
[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
7 kahiji (ieu 0b111 dina ngagambarkeun bit) dina parameter hartina "sagala hak pikeun nu boga", kadua 6 (ieu 0b110 dina ngagambarkeun bit) hartina "maca jeung nulis", jeung 0 hartina nanaon keur sésana. . Bitmask diwangun ku tilu bit: bit sahenteuna signifikan ("katuhu") tanggung jawab palaksanaan, bit salajengna ("tengah") pikeun nulis, sarta bit paling signifikan ("kénca") pikeun maca.
Anjeun ogé tiasa nyetél idin nganggo karakter khusus (sintaksis mnemonic). Salaku conto, conto di handap ieu mimiti ngaleungitkeun hak palaksanaan pikeun pangguna ayeuna teras robih deui:
[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
Paréntah ieu seueur kagunaan, janten kuring mamatahan anjeun maca langkung seueur ngeunaan éta (khususna ngeunaan sintaksis mnemonic, contona, ).
Nyitak eusi file binér
Ieu tiasa dilakukeun nganggo utiliti hexdump. Di handap ieu conto pamakéan na.
[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
Nganggo utiliti ieu, anjeun tiasa ngaluarkeun data dina format anu sanés, tapi ieu mangrupikeun pilihan anu paling sering kapaké pikeun ngagunakeunana.
Pilarian file
Anjeun tiasa mendakan file ku bagian tina namina dina tangkal diréktori nganggo paréntah manggih:
[user@testhost ~]$ find test_dir/ -name "*le*"
test_dir/file_1
test_dir/file_2
test_dir/subdir/file_3
pilihan pilarian sejen tur saringan oge sadia. Salaku conto, ieu kumaha anjeun tiasa mendakan file dina polder ujiandijieun leuwih ti 5 poé ka tukang:
[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
Pilarian téks dina file
Tim bakal nulungan anjeun Cope jeung tugas ieu grep. Éta ngagaduhan seueur kagunaan, anu pangbasajanna dirumuskeun di dieu salaku conto.
[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
Salah sahiji cara anu populér pikeun ngagunakeun paréntah grep - ngagunakeun éta dina pipa (pipah):
[user@testhost ~]$ sudo tail -f /var/log/test.log | grep "ERROR"
Pilihan -v ngidinan Anjeun pikeun nyieun pangaruh grep'sareng sabalikna - ukur garis anu henteu ngandung pola anu dikirimkeun ka grep.
Ningali bungkusan anu dipasang
Henteu aya paréntah universal, sabab sadayana gumantung kana distribusi Linux sareng manajer pakét anu dianggo. Paling dipikaresep salah sahiji paréntah di handap ieu bakal nulungan anjeun:
yum list installed
apt list --installed
zypper se —installed-only
pacman -Qqe
dpkg -l
rpm -qa
Tempo sabaraha spasi tangkal diréktori nyokot up
Salah sahiji pilihan pikeun ngagunakeun paréntah du:
[user@testhost ~]$ du -h -d 1 test_dir/
8,0K test_dir/subdir
20K test_dir/
Anjeun tiasa ngarobah nilai parameter -dpikeun meunangkeun inpo nu leuwih lengkep ngeunaan tangkal diréktori. Anjeun oge bisa make paréntah dina kombinasi jeung dipilihan:
[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
Pilihan -h tim dipilihan ngidinan Anjeun pikeun nyortir ukuran ditulis dina format bisa dibaca manusa (contona, 1K, 2G), pilihan -r ngidinan Anjeun pikeun nyortir data dina urutan sabalikna.
"Panggihan sareng ganti" dina file, dina file dina diréktori
Operasi ieu dilaksanakeun nganggo utiliti séd (teu aya bandéra g dina tungtungna, ngan kajadian mimiti "teks heubeul" dina garis bakal diganti):
sed -i 's/old-text/new-text/g' input.txt
Anjeun tiasa dianggo pikeun sababaraha file sakaligus:
[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
Tarik kolom tina kaluaran
Bakal mantuan pikeun Cope jeung tugas ieu ahk. Conto ieu mintonkeun kolom kadua kaluaran paréntah `ps ux`:
[user@testhost ~]$ ps ux | awk '{print $2}'
PID
11023
25870
25871
25908
25909
Dina waktos anu sami, éta kedah émut yén ahk boga pungsi loba richer, jadi lamun kudu digawekeun ku téks dina garis paréntah, Anjeun kudu maca leuwih lengkep tentang paréntah ieu.
Panggihan alamat IP ku hostname
Salah sahiji paréntah di handap ieu bakal ngabantosan ieu:
[user@testhost ~]$ 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
Émbaran jaringan
Bisa dianggo 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
Atawa meureun 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
Sumawona, upami, contona, anjeun ngan ukur resep IPv4, maka anjeun tiasa nambihan pilihan -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
Nempo palabuhan kabuka
Jang ngalampahkeun ieu, nganggo utiliti netstat. Salaku conto, pikeun ningali sadaya palabuhan déngékeun TCP sareng UDP kalayan tampilan PID tina prosés déngékeun dina port sareng perwakilan numerik port, anjeun kedah nganggo éta kalayan pilihan ieu:
[user@testhost ~]$ netstat -lptnu
Inpo Sistim
Anjeun tiasa kéngingkeun inpormasi ieu nganggo paréntah 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
Pikeun ngartos format dimana kaluaran dihasilkeun, anjeun tiasa ningali Tulung'pikeun paréntah ieu:
[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
Émbaran mémori
Pikeun ngartos sabaraha RAM anu dijajah atanapi gratis, anjeun tiasa nganggo paréntah bebas.
[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
Inpormasi ngeunaan sistem file (ruang disk bébas)
regu df ngidinan Anjeun pikeun ningali sabaraha spasi bébas tur nempatan dina sistem file dipasang.
[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
Pilihan -T netepkeun yén jinis sistem file kedah disimpulkeun.
Inpormasi ngeunaan tugas sareng rupa-rupa statistik dina sistem
Jang ngalampahkeun ieu, nganggo paréntah puncak. Éta sanggup nampilkeun sababaraha inpormasi: contona, prosés luhur ku pamakean RAM atanapi prosés luhur ku pamakean waktos CPU. Éta ogé nunjukkeun inpormasi ngeunaan mémori, CPU, uptime sareng LA (rata-rata beban).
[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
Utiliti ieu ngagaduhan pungsionalitas anu beunghar, janten upami anjeun kedah sering dianggo, langkung saé maca dokuméntasina.
Dump lalulintas jaringan
Pikeun ngahalangan lalu lintas jaringan dina Linux, utilitas dianggo tcpdump. Pikeun miceun lalu lintas dina port 12345, anjeun tiasa nganggo paréntah di handap ieu:
[user@testhost ~]$ sudo tcpdump -i any -A port 12345
Pilihan -A nyebutkeun yen urang hoyong ningali kaluaran dina ASCII (jadi éta alus pikeun protokol téks), -abdi wae nunjukkeun yén kami henteu resep kana antarmuka jaringan, palabuhan - lalulintas port mana pikeun dump. Sabalikna palabuhan anjeun bisa make nu boga imah, atawa kombinasi nu boga imah и palabuhan (host A jeung port X). pilihan séjén mangpaat bisa jadi -n - ulah ngarobah alamat kana hostnames dina kaluaran.
Kumaha upami lalulintas binér? Lajeng pilihan bakal nulungan urang -X - data kaluaran dina hex sareng ASCII:
[user@testhost ~]$ sudo tcpdump -i any -X port 12345
Perlu diperhatoskeun yén dina dua kasus pamakean pakét IP bakal kaluaran, janten dina awal masing-masing bakal aya IP binér sareng lulugu TCP. Ieu conto kaluaran pikeun query "123"Dikirim ka server ngadangukeun dina 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 .........
Gantina output
Tangtosna, aya seueur hal anu langkung narik dina Linux anu anjeun tiasa maca ngeunaan Habré, StackOverflow sareng situs sanésna (kuring masihan anjeun conto , anu ogé ). Administrator sistem sareng DevOps nganggo langkung seueur paréntah sareng utilitas pikeun ngonpigurasikeun server, tapi bahkan panguji tiasa henteu cekap tina paréntah anu didaptarkeun. Anjeun bisa jadi kudu pariksa correctness tina sababaraha timeout tricky antara klien tur server, atawa operasi server lamun euweuh spasi disk bébas. Kuring malah teu ngawangkong ngeunaan, contona, Docker, nu ayeuna aktip dipake ku loba pausahaan. Naha éta pikaresepeun, salaku bagian tina neraskeun tulisan rujukan ieu, ningali sababaraha conto ngagunakeun sababaraha utilitas konsol Linux dina prosés nguji jasa? Bagikeun ogé tim top anjeun dina koméntar :)
sumber: www.habr.com