Mikrotik: BFD Deteksi Link Failure

Berikut panduan lengkap & praktis setting BFD untuk BGP di MikroTik RouterOS (v6 & v7), fokus ke fast convergence saat link putus.

Konsep Singkat (Penting)

• BFD ≠ BGP BFD hanya deteksi link mati super cepat (ms)
• BGP pakai hasil BFD Saat BFD down → BGP langsung withdraw route

Target:

• ⏱️ **Default BGP:** 1–3 menit ❌
• ⚡ **BGP + BFD:** < **300 ms** 🔥

1️⃣ Cek Versi RouterOS

/system resource print

RouterOS	Status
v6.43+	BFD tersedia
v7.x	BFD 'lebih stabil & recommended

2️⃣ Konfigurasi BFD (WAJIB)

Contoh Parameter Aman & Cepat

/routing bfd configuration
add interfaces=ether1 min-tx=100ms min-rx=100ms multiplier=3

Artinya:

• Kirim paket tiap **100 ms**
• Deteksi mati: **300 ms**
• Cocok untuk **fiber / radio bagus / LAN**

⚠️ Jangan pakai <50ms di wireless jelek

3️⃣ Aktifkan BFD di Peer BGP (RouterOS v7)

/routing bgp connection
set [find name=peer-ISP] bfd=yes

Atau saat membuat peer:

/routing bgp connection
add name=peer-ISP \
    remote.address=192.168.10.1 \
    remote.as=65001 \
    local.as=65000 \
    bfd=yes

4️⃣ (Opsional) Percepat Timer BGP

• Jika **tanpa BFD**, timer ini penting
• Jika **pakai BFD**, timer ini backup only

/routing bgp connection
set peer-ISP keepalive-time=10s hold-time=30s

5️⃣ Verifikasi BFD (WAJIB)

Cek Status BFD

/routing bfd session print

Status normal:

state=up

Jika:

state=down

➡️ BGP langsung disconnect

6️⃣ Test Fast Failover

Cara Aman Test

• Cabut kabel fiber
• Shutdown interface upstream
• Disable VLAN

Pantau:

/routing bgp session print
/ip route print where bgp

⏱️ Harus turun < 1 detik

7️⃣ Topologi Paling Umum (Dual Link)

• https://data-discourse.cdn.mikrotik.com/original/3X/8/8/88994367cafc6525e7606588f6faad1b9a15b694.png

• https://i.imgur.com/huowhnq.png

• https://www.researchgate.net/publication/335142069/figure/fig3/AS%3A1095918434684930%401638298724943/OpenFlow-fast-failover-group-BFD-bidirectional-forwarding-detection-LOS-loss-of-signal.png

8️⃣ Best Practice BFD di MikroTik

• Gunakan RouterOS v7
• Aktifkan 1 BFD per interface, bukan per peer
• Jangan terlalu agresif di wireless
• Kombinasikan dengan ECMP bila multi-link

Rekomendasi Setting Cepat & Stabil

/routing bfd configuration
add interfaces=ether1 min-tx=100ms min-rx=100ms multiplier=3

/routing bgp connection
set peer-ISP bfd=yes keepalive-time=10s hold-time=30s

Kesalahan Umum

• Lupa enable `bfd=yes` di BGP peer
• Timer BFD terlalu kecil → flapping
• Peer ISP tidak support BFD (cek dulu!)

Ringkasan

Item	Nilai
BFD detect	300 ms
BGP fallback	30 detik
Failover real	< 1 detik
Cocok untuk	ISP, Kampus, DC, Tambang