Cisco : Trunk

Cisco : Trunk

Trunk adalah sebuah koneksi jaringan yang digunakan untuk membawa lalu lintas dari banyak VLAN secara bersamaan melalui satu link fisik. Konsep trunk ini umum digunakan dalam jaringan switch untuk menghubungkan perangkat jaringan tanpa perlu menyediakan satu kabel untuk setiap VLAN, sehingga topologi jaringan menjadi lebih efisien dan skalabel. Dengan trunk, pemisahan jaringan secara logis tetap terjaga meskipun data dari berbagai VLAN melewati jalur yang sama.

Syntax

Konfigurasi trunks links

Perintah Konfigurasi Trunk

Command	Description
`S1(config)#interface [int-id]`	Masuk ke mode konfigurasi interface
`S1(config-if)#switchport mode trunk`	Mengatur interface ke mode trunk
`S1(config-if)#switchport trunk native vlan [vlan-id]`	Menentukan native VLAN (frame tanpa tag)
`S1(config-if)#switchport trunk allowed vlan [vlan-list]`	Menentukan VLAN yang diizinkan pada trunk (gunakan `all` untuk semua VLAN)
`S1(config-if)#switchport trunk allowed vlan remove [vlan-id]`	Menghapus VLAN tertentu dari daftar trunk

Contoh:

interface GigabitEthernet1/0 
  switchport mode trunk 
  switchport trunk native vlan 99 
  switchport trunk allowed vlan 10,20,99

Troubleshooting Trunk

Command	Description
`S1#show interfaces trunk`	Menampilkan VLAN yang diizinkan pada trunk

Topologi

Pada toplogy terdapat 2 jaringan yang berbeda yaitu BIRU : 192.168.1.0/24 dengan VLAN 10 dan MAGENTA : 192.168.2.0/24 dengan VLAN 20. Interface gigabitethernet0/1 akan menjadi links trunks yang mengubungkan vlan atas dan bawah.

VLAN 10 - PC1,PC2,PC5,PC6 (BIRU)
VLAN 20 - PC3,PC4,PC7,PC8 (MAGENTA)

Konfigurasi

Konfigurasi VLANs

Step 1 : Menset vlan 10,20 pada masing masing switch

SW1(config)#vlan 10
SW1(config-vlan)#name BIRU
SW1(config-vlan)#exit
SW1(config)#vlan 20
SW1(config-vlan)#name MAGENTA
SW1(config-vlan)#exit

SW2(config)#vlan 10
SW2(config-vlan)#name BIRU
SW2(config-vlan)#exit
SW2(config)#vlan 20
SW2(config-vlan)#name MAGENTA
SW2(config-vlan)#exit

Step 2 : Mengatur ports sesuai VLAN.

SW1(config)#interface range f0/1-2
SW1(config-if-range)#switchport mode access
SW1(config-if-range)#switchport access vlan 10
SW1(config)#interface range f0/3-4
SW1(config-if-range)#switchport mode access
SW1(config-if-range)#switchport access vlan 20

SW2(config)#interface range f0/1-2
SW2(config-if-range)#switchport mode access
SW2(config-if-range)#switchport access vlan 10
SW2(config-if-range)#exit
SW2(config)#interface range f0/3-4
SW2(config-if-range)#switchport mode access
SW2(config-if-range)#switchport access vlan 20

Konfigurasi Trunk

Step 1 : Mengatur trunk pada sisi SW1.

SW1(config)#interface g0/1
SW1(config-if)#switchport mode trunk
SW1(config-if)#do show interfaces trunk
Port        Mode         Encapsulation  Status        Native vlan
Gig0/1      on           802.1q         trunking      1

Port        Vlans allowed on trunk
Gig0/1      1-1005

Port        Vlans allowed and active in management domain
Gig0/1      1,10,20

Port        Vlans in spanning tree forwarding state and not pruned
Gig0/1      1,10,20

SW1(config-if)#switchport trunk allowed vlan 10,20
SW1(config-if)#do show interfaces trunk
Port        Mode         Encapsulation  Status        Native vlan
Gig0/1      on           802.1q         trunking      1

Port        Vlans allowed on trunk
Gig0/1      10,20

Port        Vlans allowed and active in management domain
Gig0/1      10,20

Port        Vlans in spanning tree forwarding state and not pruned
Gig0/1      20

SW1(config-if)#exit

Step 2 : Mengatur trunk pada sisi SW2.

SW2(config)#interface g0/1
SW2(config-if)#switchport mode trunk
SW2(config-if)#switchport trunk allowed vlan 10,20
SW2(config-if)#

Testing

PC1 → PC6,PC8

C:\>ping 192.168.1.4

Pinging 192.168.1.4 with 32 bytes of data:

Reply from 192.168.1.4: bytes=32 time<1ms TTL=128
Reply from 192.168.1.4: bytes=32 time<1ms TTL=128
Reply from 192.168.1.4: bytes=32 time<1ms TTL=128
Reply from 192.168.1.4: bytes=32 time<1ms TTL=128

Ping statistics for 192.168.1.4:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms

C:\>ping 192.168.2.4

Pinging 192.168.2.4 with 32 bytes of data:

Request timed out.
Request timed out.
Request timed out.
Request timed out.

Ping statistics for 192.168.2.4:
    Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),

PC3 → PC6,PC8

C:\>ping 192.168.1.4

Pinging 192.168.1.4 with 32 bytes of data:

Request timed out.
Request timed out.
Request timed out.
Request timed out.

Ping statistics for 192.168.1.4:
    Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),

C:\>ping 192.168.2.4

Pinging 192.168.2.4 with 32 bytes of data:

Reply from 192.168.2.4: bytes=32 time<1ms TTL=128
Reply from 192.168.2.4: bytes=32 time<1ms TTL=128
Reply from 192.168.2.4: bytes=32 time<1ms TTL=128
Reply from 192.168.2.4: bytes=32 time<1ms TTL=128

Ping statistics for 192.168.2.4:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms

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