1. Tarmoq buyruqlari

🎯 Bu bobda nimani o'rganasiz:
ping — eng oddiy reachability test
curl — HTTP klient (DevOps'ning kundalik vositasi)
REST API'ga GET/POST/PUT/DELETE so'rovlar
JSON body + headers + autentifikatsiya (Basic, Bearer)
wget — fayl yuklash + retry mantiq
dig, nc, ss — DNS va port asoslari
Real misol — URL monitor (sayt yiqilganini aniqlash)
⏱ Vaqt: ~40 daqiqa 🧪 Mashqlar: bashlings watch 11_network (kelajak sprint)

1.1. Tarmoq vositalari nima uchun kerak?

Bir kun ish:

API yiqilganini tekshirish — curl -fsS https://api.example.com/health
Production database'ning portini sinash — nc -zv db.internal 5432
DNS o'zgarishini tasdiqlash — dig +short example.com
Saytdan fayl yuklash — wget https://example.com/data.tar.gz
Internal monitoring uchun status code tahlili — curl -o /dev/null -w "%{http_code}"

Bularning hammasi standart Unix vositalari bilan, hech qanday Python yoki Go yozmasdan amalga oshiriladi.

Asosiy g'oya

Shell + curl kombinatsiyasi — production debugging uchun eng tezkor yo'l. Browser ochmasdan, IDE'siz, faqat terminal.

1.2. `ping` — eng oddiy reachability test

bash

ping google.com
# PING google.com (142.250.184.46): 56 data bytes
# 64 bytes from 142.250.184.46: icmp_seq=0 ttl=115 time=8.5 ms
# ...

ICMP echo paketlarini yuboradi va javobni kutadi. Asosiy diagnostik vosita.

Foydali flaglar

Flag	Mazmuni
`-c <son>`	Aniq son so'rov yuborib chiqarish
`-W <ms>`	Timeout (millisekund)
`-i <son>`	Yuboruvchi oraliq (soniya)
`-s <bayt>`	Paket hajmi

bash

# 4 marta yuborib chiqish
ping -c 4 google.com

# Tezroq tekshirish (3 ta, 1 soniya timeout har bittasi uchun)
ping -c 3 -W 1000 myserver.com

Korporativ tarmoqlar

Ko'pchilik bulutli hostlar ICMP'ni o'chirib qo'yadi — ping ishlamasligi server yiqilganini anglatmaydi. HTTP/TCP testi ishonchliroq.

1.3. `curl` — HTTP klient asoslari

curl — eng muhim tarmoq buyrug'i. Har Unix tizimda mavjud (yoki bir buyruq bilan o'rnatiladi).

Eng oddiy GET

bash

curl https://api.github.com/zen
# Practicality beats purity.

curl <URL> — sukut bo'yicha GET so'rov, response body'ni stdout'ga chiqaradi.

Klassik foydali flaglar

Flag	Mazmuni
`-s`	Silent — progress va xato xabarlarini yashirish
`-S`	`-s` bilan birga: xato xabarlarni ko'rsatish (best practice)
`-f`	Status code 4xx/5xx bo'lsa exit code non-zero (skriptlar uchun)
`-i`	Response headers'ni body bilan birga chiqarish
`-I`	Faqat headers (HEAD so'rov)
`-L`	Redirect'larni avtomatik kuzatish
`-o <fayl>`	Faylga yozish
`-O`	URL'dagi nomi bilan saqlash
`-X <metod>`	HTTP metodni belgilash (GET/POST/PUT/DELETE/...)
`-H 'K: V'`	Custom header
`-d '...'`	Request body (sukut bo'yicha POST qiladi)
`-u user:pass`	Basic auth
`-w "format"`	Yakuniy ma'lumotlar (status code, vaqt, hajm)

Skript uchun standart kombinatsiya

bash

curl -fsSL https://example.com/install.sh | bash

Flag	Sabab
`-f`	404 bo'lsa script'ni bash'ga uzatmaslik
`-s`	Progress bar shovqinini o'chirish
`-S`	Lekin haqiqiy xatolar ko'rinsin
`-L`	Redirect'larni kuzatish (download serverlari)

Production'da -fsSL — standart

Bu kombinatsiya shellda eng ko'p uchraydigan curl invokatsiyasi. Esda saqlang: -fsSL.

1.4. Response inspecting — status code va vaqtlar

Faqat status code

bash

curl -s -o /dev/null -w "%{http_code}\n" https://example.com
# 200

%{http_code} — -w format'dagi maxsus token. Boshqa foydali tokenlar:

Token	Mazmuni
`%{http_code}`	HTTP status
`%{time_total}`	Umumiy vaqt (soniya)
`%{time_connect}`	TCP connect vaqti
`%{time_starttransfer}`	TTFB (Time To First Byte)
`%{size_download}`	Yuklangan hajm (bayt)
`%{url_effective}`	Yakuniy URL (redirect'lardan keyin)

To'liq tahlil

bash

curl -s -o /dev/null -w \
  "status: %{http_code}\ntime: %{time_total}s\nsize: %{size_download} bytes\n" \
  https://example.com

text

status: 200
time: 0.234s
size: 1256 bytes

Headers ko'rish

bash

curl -I https://example.com
# HTTP/2 200
# content-type: text/html; charset=UTF-8
# cache-control: max-age=604800
# ...

-I — faqat headers (HEAD so'rov). Server tipini, cache sozlamalarini, redirectlarni tekshirish uchun ideal.

1.5. POST + JSON body — API bilan ishlash

Oddiy POST (form-urlencoded)

bash

curl -X POST https://httpbin.org/post \
  -d 'name=Ali&age=25'

-d flag berilsa, curl avtomatik POST qiladi.

JSON body yuborish

bash

curl -X POST https://httpbin.org/post \
  -H "Content-Type: application/json" \
  -d '{"name":"Ali","age":25}'

Faylda JSON body

bash

cat > payload.json <<EOF
{
  "user": "Ali",
  "city": "Toshkent"
}
EOF

curl -X POST https://httpbin.org/post \
  -H "Content-Type: application/json" \
  -d @payload.json

@filename — fayldan content olish.

PUT va DELETE

bash

curl -X PUT https://api.example.com/users/42 \
  -H "Content-Type: application/json" \
  -d '{"name":"Ali"}'

curl -X DELETE https://api.example.com/users/42

1.6. Autentifikatsiya

Basic auth

bash

curl -u username:password https://api.example.com/data

Yoki interaktiv (parol so'raydi):

bash

curl -u username https://api.example.com/data

Bearer token (eng keng tarqalgan)

bash

TOKEN="xyz123abc..."
curl -H "Authorization: Bearer $TOKEN" https://api.example.com/me

bash

# Cookie'larni faylga saqlash va keyingi so'rovlarda ishlatish
curl -c cookies.txt -d "user=ali&pass=secret" https://example.com/login
curl -b cookies.txt https://example.com/dashboard

Secrets va shell history

Parolni argument sifatida bersangiz (-u user:password), u bash history'ga tushadi. Yaxshiroq yo'l:

bash

read -sp "Parol: " PASS
curl -u "user:$PASS" https://...

Yoki environment variable + secrets manager.

1.7. `wget` — fayl yuklash

wget curl ga muqobil, lekin fayl yuklash uchun mo'ljallangan.

bash

# Sodda yuklash
wget https://example.com/data.tar.gz

# Boshqa nom bilan saqlash
wget -O myfile.tar.gz https://example.com/data.tar.gz

# Tinch rejim (progress yo'q)
wget -q https://example.com/file

# Retry — 5 marta urinish, har biri orasida 10s
wget --tries=5 --wait=10 https://example.com/file

# Recursive (sayt arxivlash) — diqqat: katta saytlar uchun xavfli
wget -r -np -k https://example.com/docs/

`curl` vs `wget`

Xususiyat	`curl`	`wget`
Default chiqish	stdout	fayl
HTTP method'lar (POST, PUT, ...)	✅ to'liq	cheklangan
Retry / recursive download	manual	✅ built-in
Resume yarim tushgan yuklash	`-C -`	`-c`
Header'lar bilan ishlash	✅ asosiy	cheklangan

Qoida

API bilan ishlasangiz — curl. Saytdan fayl yuklasangiz — wget.

1.8. DNS — `dig`, `host`, `nslookup`

dig (Domain Information Groper) — DNS so'rovlari uchun eng kuchli vosita.

bash

# Sodda A record so'rovi
dig example.com
# (uzun chiqish — barcha sections)

# Faqat IP — qisqartirilgan
dig +short example.com
# 93.184.216.34

# MX record (mail server)
dig +short MX gmail.com

# NS record (name servers)
dig +short NS example.com

# Boshqa DNS server orqali (Google's 8.8.8.8)
dig @8.8.8.8 example.com

# Teskari (reverse) DNS
dig -x 8.8.8.8

`host` va `nslookup` — qisqartirilgan

bash

host example.com
# example.com has address 93.184.216.34
# example.com has IPv6 address 2606:2800:220:1:248:1893:25c8:1946

nslookup example.com
# (eski uslub, hali ham ishlatiladi)

Real misol — DNS caching tekshirish

bash

# 5 sekundlik intervallar bilan 6 marta
for i in $(seq 1 6); do
    dig +short example.com
    sleep 5
done

Agar IP turli javoblardan kelsa — load balancing yoki round-robin DNS bor.

1.9. `nc` (netcat) — Swiss army knife

nc — TCP/UDP uchun universal vosita.

Port band ekanligini tekshirish

bash

# -z = zero-I/O (faqat tekshirish)
# -v = verbose
nc -zv example.com 80
# Connection to example.com port 80 [tcp/http] succeeded!

nc -zv example.com 443
# Connection to example.com port 443 [tcp/https] succeeded!

nc -zv example.com 22
# nc: connectx to example.com port 22 (tcp) failed: Operation timed out

Timeout bilan (kerakli skriptlar uchun)

bash

nc -zv -w 3 example.com 80   # 3 soniya timeout

Quick TCP server (debug uchun)

bash

# Terminal A — listen
nc -l 8080

# Terminal B — connect
echo "salom" | nc localhost 8080

# Terminal A endi "salom" qabul qiladi

Production debug

Database portini tekshirish — nc -zv db.internal 5432. Eng tezkor "DB ishlayaptimi?" testi.

1.10. `ss` va `netstat` — lokal portlar

`ss` — zamonaviy (Linux)

bash

# Listen qilayotgan portlar
ss -tlnp
# t — TCP, l — listening, n — raqamlar (DNS resolve qilmaslik), p — PID

# Hamma TCP ulanishlar
ss -tan

# UDP portlar
ss -ulnp

`netstat` — eski klassik

bash

# Listening TCP portlar
netstat -tlnp     # Linux
netstat -an | grep LISTEN   # macOS (BSD netstat boshqacha)

# Hamma TCP ulanishlar
netstat -tan

`lsof` — eng informativ (port + process)

bash

# 8080 portni qaysi jarayon ishlatadi?
lsof -i :8080
# COMMAND   PID  USER   FD   TYPE  NODE NAME
# node    12345 mac    23u  IPv6  ...  TCP *:8080 (LISTEN)

Klassik debug

"8080 port band" → lsof -i :8080 → PID → kill PID.

1.11. Real misol — URL Monitor

To'liq production-grade misol:

bash

#!/usr/bin/env bash
#
# monitor.sh — bir nechta URL'ni har 60 soniyada tekshirib turish
#

set -euo pipefail

readonly URLS=(
    "https://example.com"
    "https://api.github.com/zen"
    "https://httpbin.org/status/200"
)

readonly TIMEOUT=10           # soniya
readonly INTERVAL=60          # tekshirish oralig'i
readonly LOG_FILE="${LOG_FILE:-/tmp/monitor.log}"

# Ranglar (TTY bo'lsa)
if [[ -t 1 ]]; then
    GREEN='\033[32m'; RED='\033[31m'; RESET='\033[0m'
else
    GREEN=''; RED=''; RESET=''
fi

log() {
    local ts; ts=$(date '+%Y-%m-%d %H:%M:%S')
    printf '[%s] %s\n' "$ts" "$*" | tee -a "$LOG_FILE"
}

check_url() {
    local url="$1"
    local status time_total
    
    # -s silent, -o /dev/null body'ni tashlash,
    # -w bilan formatni ushlash, --max-time timeout
    if ! read -r status time_total < <(
        curl -s -o /dev/null \
            --max-time "$TIMEOUT" \
            -w '%{http_code} %{time_total}\n' \
            "$url" 2>/dev/null
    ); then
        echo "TIMEOUT 0"
        return
    fi
    echo "$status $time_total"
}

check_all() {
    for url in "${URLS[@]}"; do
        read -r status time_total < <(check_url "$url")
        
        if [[ "$status" == "200" ]]; then
            printf '%b✓%b %s — %s in %ss\n' "$GREEN" "$RESET" "$url" "$status" "$time_total"
            log "OK $url $status ${time_total}s"
        else
            printf '%b✗%b %s — %s\n' "$RED" "$RESET" "$url" "$status"
            log "FAIL $url $status"
        fi
    done
}

# Asosiy loop
log "Monitor boshlandi (PID: $$)"
trap 'log "Monitor to`xtatildi"; exit 0' INT TERM

while true; do
    echo "──── $(date '+%H:%M:%S') ────"
    check_all
    sleep "$INTERVAL"
done

Ishga tushirish:

bash

chmod +x monitor.sh
./monitor.sh             # foreground
./monitor.sh &           # background
nohup ./monitor.sh &     # terminal yopilsa ham davom etsin

Bu skript nima qiladi?

Xususiyat	Qaerda
Multiple URL	`URLS=()` massiv
Timeout har so'rov uchun	`--max-time $TIMEOUT`
Status va vaqtni bir paketda olish	`curl -w '%{http_code} %{time_total}'`
Color (faqat TTY)	`[[ -t 1 ]]` check
Log faylga ham yozish	`tee -a "$LOG_FILE"`
Graceful shutdown	`trap ... INT TERM`
Cheksiz loop	`while true; do ... sleep ... done`

1.12. Tez-tez uchraydigan xatolar

Klassik tuzoqlar

-s bilan xatolarni yashirish.curl -s rejimi xato xabarlarini ham yashiradi. curl -sS — silent + show errors. Har doim -sS kombinatsiyasi.

Status code'ni shell'da tekshirmaslik.

bash

curl https://api.com/fail   # exit 0, lekin status 500!
curl -f https://api.com/fail # exit 22 (4xx/5xx)

Redirect'larni unutish.curl https://github.com → 301. Sizning skriptingiz redirect ko'rmaydi. curl -L ishlating.
Parolni argument sifatida berish.curl -u user:secret — bash history'da saqlanadi. read -sp orqali oling.
wget -r ehtiyotsizlik. Recursive — millionlab fayl yuklashi mumkin. --max-depth=3 va --no-parent qo'shing.
macOS netstat va Linux netstat — boshqa flaglar.netstat -tlnp Linux'da ishlaydi, macOS'da ishlamaydi. ss Linux-only, macOS'da lsof -i ishlating.
DNS cache ehtiyotkorlik.dig har gal yangi so'rov yuboradi. Lekin tizim getent yoki /etc/hosts cache'iga ishonishi mumkin.
nc versiyalari farqli.nc -z (zero-I/O) — GNU netcat'da bor, BSD netcat (macOS)'da ham bor. nc -k (keep-listening) faqat BSD'da. Versiyangizni nc -h bilan tekshiring.

1.13. Mashqlar

🧪 Kelajakda bashlings watch 11_network paketida.

Status checker — https://httpbin.org/status/200, https://httpbin.org/status/404, https://httpbin.org/status/500 URL'lari uchun status code'larni chiqaring (har bittasi alohida qatorda).
Response time — biror sayt uchun TTFB (%{time_starttransfer}) ni o'lchang va "TTFB: X.XXs" formatida chiqaring.
JSON POST — https://httpbin.org/post ga JSON body yuboring ({"city": "Toshkent"}) va javobdan headers.Content-Type ni jq bilan ajratib oling (jq keyingi bobda).
Port scanner — bir hostda 22, 80, 443, 8080 portlarini nc -zv bilan tekshiruvchi mini skript yozing. Har port uchun "OPEN" yoki "CLOSED" chiqarsin.
DNS comparator — bir domeni 3 ta turli DNS serverda (8.8.8.8 Google, 1.1.1.1 Cloudflare, 9.9.9.9 Quad9) tekshirib, javoblar farqli yoki teng ekanligini chiqarsin.

1.14. Xulosa

Tushuncha	Asosiy nuqta
`ping -c N host`	ICMP reachability tekshiruv
`curl URL`	Sodda GET
`curl -fsSL URL`	Skriptlar uchun standart kombinatsiya
`curl -X POST -d ...`	POST so'rov
`curl -H "K: V"`	Custom header
`curl -u user:pass`	Basic auth
`curl -H "Authorization: Bearer $T"`	Token auth
`curl -w "%{http_code}"`	Status + metrika
`curl -L`	Redirect'larni kuzatish
`wget URL`	Fayl yuklash
`wget -c URL`	Yarim tushgan'ni davom ettirish
`dig +short example.com`	Sodda DNS so'rovi
`nc -zv host port`	Port band-bandligini tekshirish
`lsof -i :8080`	8080 ni qaysi jarayon ishlatadi?

5 ta asosiy g'oya

curl -fsSL — har skriptda ishlatiladigan standart kombinatsiya
-w flag — status code va vaqtlarni bir buyruqda ushlash
API bilan ishlash: curl HTTP'ning hamma metodini qo'llab-quvvatlaydi (GET/POST/PUT/DELETE/PATCH/...)
nc -zv host port — eng tezkor "port band-bandligini" testi
dig +short — DNS debug'i uchun har production muhandisi bilishi kerak

🎉 Endi sizda REST API bilan ishlash asoslari bor. Keyingi bobda — SSH orqali masofadagi serverlarga ulanish va scp/rsync orqali fayllarni ko'chirish.

Keyingi sahifa: 2. SSH va remote management →

1. Tarmoq buyruqlari ​

1.1. Tarmoq vositalari nima uchun kerak? ​

1.2. ping — eng oddiy reachability test ​

Foydali flaglar ​

1.3. curl — HTTP klient asoslari ​

Eng oddiy GET ​

Klassik foydali flaglar ​

Skript uchun standart kombinatsiya ​

1.4. Response inspecting — status code va vaqtlar ​

Faqat status code ​

To'liq tahlil ​

Headers ko'rish ​

1.5. POST + JSON body — API bilan ishlash ​

Oddiy POST (form-urlencoded) ​

JSON body yuborish ​

Faylda JSON body ​

PUT va DELETE ​

1.6. Autentifikatsiya ​

Basic auth ​

Bearer token (eng keng tarqalgan) ​

Cookie ​

1.7. wget — fayl yuklash ​

curl vs wget ​

1.8. DNS — dig, host, nslookup ​

host va nslookup — qisqartirilgan ​

Real misol — DNS caching tekshirish ​

1.9. nc (netcat) — Swiss army knife ​

Port band ekanligini tekshirish ​

Timeout bilan (kerakli skriptlar uchun) ​

Quick TCP server (debug uchun) ​

1.10. ss va netstat — lokal portlar ​

ss — zamonaviy (Linux) ​

netstat — eski klassik ​

lsof — eng informativ (port + process) ​

1.11. Real misol — URL Monitor ​

Bu skript nima qiladi? ​

1.12. Tez-tez uchraydigan xatolar ​

1.13. Mashqlar ​

1.14. Xulosa ​

5 ta asosiy g'oya ​

1. Tarmoq buyruqlari

1.1. Tarmoq vositalari nima uchun kerak?

1.2. `ping` — eng oddiy reachability test

Foydali flaglar

1.3. `curl` — HTTP klient asoslari

Eng oddiy GET

Klassik foydali flaglar

Skript uchun standart kombinatsiya

1.4. Response inspecting — status code va vaqtlar

Faqat status code

To'liq tahlil

Headers ko'rish

1.5. POST + JSON body — API bilan ishlash

Oddiy POST (form-urlencoded)

JSON body yuborish

Faylda JSON body

PUT va DELETE

1.6. Autentifikatsiya

Basic auth

Bearer token (eng keng tarqalgan)

Cookie

1.7. `wget` — fayl yuklash

`curl` vs `wget`

1.8. DNS — `dig`, `host`, `nslookup`

`host` va `nslookup` — qisqartirilgan

Real misol — DNS caching tekshirish

1.9. `nc` (netcat) — Swiss army knife

Port band ekanligini tekshirish

Timeout bilan (kerakli skriptlar uchun)

Quick TCP server (debug uchun)

1.10. `ss` va `netstat` — lokal portlar

`ss` — zamonaviy (Linux)

`netstat` — eski klassik

`lsof` — eng informativ (port + process)

1.11. Real misol — URL Monitor

Bu skript nima qiladi?

1.12. Tez-tez uchraydigan xatolar

1.13. Mashqlar

1.14. Xulosa

5 ta asosiy g'oya