5-oyda Noldan boshlab xalqaro Cisco CCNA sertifikatini olish mumkinligini isboti mana shu bo'ladi.

Jahongirni tabriklab qolamiz.

Azizlar biz o'z yutug'larimizni shogirtlarimiz yutug'ida deb bilamiz. Va bu yutug'larni ko'paytirish harakat qilamiz.

InshaAlloh buni sizda ham isbotlashga xarakat qilamiz.

August CISCO CCNA guruhimizga ulgurib qoling

@uzbekona_cisco
@cisco_server

@new_ccna #ccna #ccnp #cisco #networking #cisco_academy

CCNA instructor material v6
Rus tilida

1-Mavzu: Tarmoqga kirish


@uzbekona_cisco
@cisco_server

@new_ccna #ccna #ccnp #cisco #networking #cisco_academy

Nimaligini biladiganlar bormi?

@uzbekona_cisco
@cisco_server

@new_ccna #ccna #ccnp #cisco #networking #cisco_academy

🎯VLAN Tag va Untag nima?

Tag nima?

Bu Ethernet framega qo'shiladigan 4 baytlik VLAN ma'lumoti (802.1Q header).
Oddiy frame: [MAC][MAC][Type][Data]
Tagged frame: [MAC][MAC][802.1Q][Type][Data]
━━━━━━━━━━━━━━━━━━━━
ACCESS PORT 🔌
Xususiyatlari:
▫️ Faqat bitta VLAN
▫️ Tagsiz paketlar
▫️ Kompyuter, printer uchun
Ishlash prinsipi:
→ Kiruvchi paketdan tagni olib tashlaydi
→ Chiquvchi paketni tagsiz yuboradi

interface Fa0/1
switchport mode access
switchport access vlan 10

━━━━━━━━━━━━━━━━━━━━
TRUNK PORT 🚀
Xususiyatlari:
▫️ Bir nechta VLAN
▫️ Tagli paketlar
▫️ Switch-switch uchun
Ishlash prinsipi:
→ Kiruvchi: Tag borini saqlaydi
→ Chiquvchi: Kopchilik VLAN tag bilan

interface Gi0/1
switchport mode trunk
switchport trunk allowed vlan 10,20,30

━━━━━━━━━━━━━━━━━━━━
Paket oqimi misoli 📊
[PC-VLAN10] —Fa0/1— [SW1] —Gi0/1— [SW2]

1️⃣ PC tagsiz paket yuboradi
2️⃣ Access port VLAN 10 tag qoshadi
3️⃣ Trunk port tag bilan uzatadi
4️⃣ SW2 tagged paketni qabul qiladi

#CCIE #VLAN #Networking #Cisco
Davomi keyingi postda 👇
@cisco_server

Kompyuterda VLAN ID o'rnatilsa nima bo'ladi? 💻
Ko'p tarmoq adapterlari VLAN taggingni qo'llab-quvvatlaydi. Lekin bu har doim kerakmi? 🤔
━━━━━━━━━━━━━━━━━━━
ACCESS PORT bilan ❌
[PC VLAN tag 10] → [Fa0/1 Access VLAN 10]
❌ Paket DROP!
Sabab: Access port faqat untagged paket kutadi, lekin tagged paket keldi!
━━━━━━━━━━━━━━━━━━━
TRUNK PORT bilan ✅
[PC VLAN tag 10] → [Gi0/1 Trunk allowed 10]
✅ VLAN 10ga yo'naladi
Shart: Trunk portda allowed vlan 10 bolishi kerak!
━━━━━━━━━━━━━━━━━━━
Xulosa 🎓
Kompyuter | Switch Port | Natija
Tag yoq | Access | ✅ Normal
Tag bor | Access | ❌ Drop
Tag bor | Trunk | ✅ Ishlaydi
━━━━━━━━━━━━━━━━━━━
Amaliy maslahat 💡
Oddiy foydalanuvchilar:
❌ VLAN tag o'rnatmang
✅ Oddiy Access portga ulang
Server/VM uchun:
✅ VLAN tagging ishlatish mumkin
✅ Trunk portga ulang
🎯 Masalan: VMware ESXi, Linux
━━━━━━━━━━━━━━━━━━━
Esda tuting! ⚠️
Kompyuterda VLAN ID yoqsangiz:
▫️ Switch TRUNK bolishi shart
▫️ Aks holda aloqa ishlamaydi
▫️ Maxsus holatlarda kerak

#CCIE #VLAN #Networking #Cisco #SwitchConfig

💬 Savollaringiz bo'lsa, komentariyada kutamiz...

@cisco_server

#Encore

📡 ENCOR 350-401 | Chapter 7

📡 EIGRP — CCNA da aytilmagan KEY POINTS
━━━━━━━━━━━━━━━━━━

🧠 DUAL Algoritmi
EIGRP oddiy distance vector emas. DUAL
(Diffusing Update Algorithm) loop-free
backup yo'llarni oldindan hisoblaydi va
convergence ni tezlashtiradi.

━━━━━━━━━━━━━━━━━━

📊 FD, RD va Feasibility Condition

- FD (Feasible Distance) — router o'zi
hisoblagan to'liq path metric

- RD (Reported Distance) — qo'shni
e'lon qilgan o'z masofasi

- Feasibility Condition:
✅ RD < FD → Feasible Successor
❌ RD ≥ FD → Backup sifatida qabul
qilinmaydi (loop xavfi)

💡 RD — bu qo'shni masofasi, to'liq
path metric emas! Path metric = RD +
o'zingning link cost.

━━━━━━━━━━━━━━━━━━

⚖️ Unequal-Cost Load Balancing

EIGRP variance multiplier orqali har xil
metrikdagi yo'llarni bir vaqtda ishlatadi.

Variance = Feasible Successor FD ÷
Successor FD (yuqoriga yaxlitlanadi)

Feasible Successor FD < Variance qiymati
bo'lsa → RIB ga o'rnatiladi.

━━━━━━━━━━━━━━━━━━

🔄 Convergence: Passive vs Active

- Passive (P) → topology barqaror ✅
- Active (A) → yo'l yo'qoldi, DUAL
hisoblash boshlandi ⚙️

Feasible Successor bor → darhol
Passive ga qaytadi (hech kim bilmaydi)

Feasible Successor yo'q → Query jarayoni
boshlanadi.

━━━━━━━━━━━━━━━━━━

📨 Query / Reply Mexanizmi

Query kelganda router MAJBURIY javob
berishi shart. 2 ta to'g'ri javob:
1️⃣ "Bu prefix menda yo'q"
2️⃣ "Menda boshqa yo'l bor" (+ attributes)

Jim qolish = o'lim 💀

Reply Status Flag — router yuborgan har
bir query uchun, har bir qo'shni bo'yicha
alohida kuzatiladi. Barcha flag = 0
bo'lganda DUAL yakunlanadi.

━━━━━━━━━━━━━━━━━━

🆘 SIA — Stuck In Active

Query ga 3 daqiqada reply kelmasa →
adjacency RESET (faqat o'sha prefix emas,
BARCHA prefix lar uchun!)

1.5 daqiqada SIA-Query yuboriladi:
"Sen tiriksan, lekin nima bo'ldi?"

Hello timer ≠ SIA-Query:
- Hello → "Qo'shni tirikmi?" (adjacency)
- SIA-Query → "DUAL hisoblash
tugatdingmi?" (computation)

Router tirik bo'la turib ham javob bera
olmasligi mumkin — chunki u ham chuqurroq
birovni kutmoqda!

━━━━━━━━━━━━━━━━━━

📦 Classic vs Wide Metrics

Classic → delay 10μs, bandwidth kbps
❌ 11 Gbps va 50 Gbps ni ajrata olmaydi

Wide → delay pikosekund (10⁻¹²),
65,536 ga ko'paytirilgan
✅ 655 Tbps gacha masshtab

K₆ → jitter, energy kabi extended
attribute lar uchun qo'shimcha qiymat

━━━━━━━━━━━━━━━━━━

🗺 Route Summarization — Null0 siri

R2 summary advertise qilganda o'z
routing table iga avtomatik:
172.16.0.0/16 → Null0 ⛔️
qo'shadi.

Mavjud bo'lmagan /24 ga paket kelsa:
→ Longest Match → Null0 → DROP
→ Loop emas, Black Hole nazorat ostida

⚠️ Summarization ishlashi uchun har bir
region ga UNIQUE address blok berilishi
shart. Bir xil summary → Black Hole!

━━━━━━━━━━━━━━━━━━
⏱️ Timers

Fast Slow (T1↓)
Hello │ 5 sec │ 60 sec
Hold │ 15 sec │ 180 sec

Hold = Hello × 3 (default)
Hold = 0 → neighbor unreachable →
DUAL ga topology change xabari

━━━━━━━━━━━━━━━━━━

#EIGRP #CCNP #ENCOR #Networking

@cisco_server

🔥 Ko'pchilik bilmagan OSPF sirlari — #1
━━━━━━━━━━━━━━━━━━
❓ Savol: Quyidagi komanda nima qiladi?

router ospf 1
  network 10.0.0.0 0.0.0.255 area 0

Ko'pchilikning fikri::

"10.0.0.0 tarmoqni OSPF ga e'lon qiladi" — NOTO'G'RI ❌

━━━━━━━━━━━━━━━━━━
✅ To'g'ri javob:
network komandasi tarmoqni emas — interfeysdagi OSPF ni YOQADI!
Keyin o'sha interfeys LSA orqali o'zi e'lon qilinadi 📡
━━━━━━━━━━━━━━━━━━
🧠 Misol bilan tushunamiz:
Router 3 ta interfeysi bor:

Gi0/0 → 10.0.0.1  ✅ mos keladi
Gi0/1 → 10.0.10.1 ❌ mos kelmaydi
Gi0/2 → 192.168.1.1 ❌ mos kelmaydi

network 10.0.0.0 0.0.0.255 area 0 👆 Bu komanda faqat Gi0/0 da OSPF ni yoqadi
━━━━━━━━━━━━━━━━━━
🎯 Wildcard mask nima qiladi?
Wildcard
Ma'nosi
0.0.0.0
Faqat aynan shu IP
0.0.0.255
/24 dagi barcha IP lar
255.255.255.255
Barcha interfeyslari
━━━━━━━━━━━━━━━━━━
💡 1 gap bilan yodla:

Network statement — tarmoq e'lon qilmaydi, interfeysdagi OSPF ni YOQADI!

━━━━━━━━━━━━━━━━━━
📌 Bu bilim CCNP/CCIE imtihonlarida tez-tez chiqadi!

👇 Buni bilardingmidingiz?
Komentariyada kutib qolamiz!


@cisco_server
#OSPF #Cisco #CCNA #CCNP #CCIE #Networking #Tarmoq