VLAN + IP addressing

 

VLAN + IP addressing ka practical combination hai, jo real network setup mein har Network Engineer use karta hai.
Main yahan simple aur clear steps mein samjhata hoon (Cisco Switch aur PC example ke sath).

🧱 Step 1: VLANs Create Karna (Switch par)

Switch> enable
Switch# configure terminal
Switch(config)# vlan 10
Switch(config-vlan)# name HR
Switch(config-vlan)# exit
Switch(config)# vlan 20
Switch(config-vlan)# name IT
Switch(config-vlan)# exit
Switch(config)# vlan 30
Switch(config-vlan)# name ACCOUNTS
Switch(config-vlan)# exit

✅ Ab VLANs switch ke andar ban chuki hain.

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🔌 Step 2: Ports Assign Karna VLANs ko

Har department ke PCs ko specific VLAN port pe connect karte ho.
Example:

Port	VLAN	Department
FastEthernet 0/2-0/5	10	HR
FastEthernet 0/6-0/9	20	IT
FastEthernet 0/10-0/13	30	Accounts

Commands:

Switch(config)# interface range fa0/2 - 5
Switch(config-if-range)# switchport mode access
Switch(config-if-range)# switchport access vlan 10
Switch(config-if-range)# exit

Switch(config)# interface range fa0/6 - 9
Switch(config-if-range)# switchport mode access
Switch(config-if-range)# switchport access vlan 20
Switch(config-if-range)# exit

Switch(config)# interface range fa0/10 - 13
Switch(config-if-range)# switchport mode access
Switch(config-if-range)# switchport access vlan 30
Switch(config-if-range)# exit

✅ Ab har department ke ports apni VLAN ke andar aa gaye.

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🌐 Step 3: IP Assign Karna (Router ya Layer 3 Switch par)

Agar ye Layer 2 switch hai, to VLANs ek doosre se communicate nahi karenge (yehi segmentation ka purpose hai).

Lekin agar tum chahte ho ke VLANs ek doosre se controlled way mein baat karein, to Router-on-a-Stick ya Layer 3 Switch use hota hai.

Example: Layer 3 Switch pe SVI create karna

Switch(config)# interface vlan 10
Switch(config-if)# ip address 192.168.10.1 255.255.255.0
Switch(config-if)# no shutdown
Switch(config-if)# exit

Switch(config)# interface vlan 20
Switch(config-if)# ip address 192.168.20.1 255.255.255.0
Switch(config-if)# no shutdown
Switch(config-if)# exit

Switch(config)# interface vlan 30
Switch(config-if)# ip address 192.168.30.1 255.255.255.0
Switch(config-if)# no shutdown
Switch(config-if)# exit

Enable Routing Between VLANs:

Switch(config)# ip routing

✅ Ab har VLAN ke devices apni gateway IP se connect ho kar routing kar sakte hain.

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💻 Step 4: PCs ko IP Assign Karna

HR PC:
IP Address: 192.168.10.10
Subnet Mask: 255.255.255.0
Default Gateway: 192.168.10.1

IT PC:
IP Address: 192.168.20.10
Subnet Mask: 255.255.255.0
Default Gateway: 192.168.20.1

Accounts PC:
IP Address: 192.168.30.10
Subnet Mask: 255.255.255.0
Default Gateway: 192.168.30.1

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✅ Result:

• HR VLAN ke PCs → sirf HR ke andar baat karenge.

• IT VLAN ke PCs → sirf IT ke andar.

• Accounts VLAN ke PCs → sirf Accounts ke andar.

• Agar routing enable hai → controlled communication VLANs ke beech possible hai.