BFD for Static Routes Configuration Problems Between the S9700 and a Non-Huawei Device

Publication Date:  2015-03-24 Views:  247 Downloads:  0
Issue Description
BFD for Static Routes Configuration Problems Between the S9700 and a Non-Huawei Device.

Applicable Products and Versions:S9700 V200R001/V200R002/V200R003

Networking
As shown in Figure 4-6, an S9700 is connected to an H3C device, the S9700's IP address belongs to 10.181.56.0/24, the H3C device's IP address belongs to 10.181.40.0/24, and dual static routes have been configured on both devices to their peer ends.

Figure 4-6 Configuration of BFD for static routes between the S9700 and H3C device



Static routes from the S9700 to the H3C device

ip route-static 10.181.40.0 255.255.255.0 10.181.70.2

ip route-static 10.181.40.0 255.255.255.0 10.181.81.2 preference 100

Static routes from the H3C device to the S9700

ip route-static 10.181.56.0 255.255.255.0 vlan-interface 70 10.181.70.1

ip route-static 10.181.56.0 255.255.255.0 vlan-interface 70 10.181.81.1 preference 100



Alarm Information
When the primary link between the two devices fails, services are interrupted because route backup fails.

Handling Process
Configure BFD for static routes on the S9700.

bfd bb bind peer-ip 10.181.70.2 interface Vlanif70 source-ip 10.181.70.1 auto
min-tx-interval 500
min-rx-interval 500
commit
ip route-static 10.181.40.0 255.255.255.0 10.181.70.2 track bfd-session bb
ip route-static 10.181.40.0 255.255.255.0 10.181.81.2
preference 100

Configure BFD for static routes on the H3C device.

interface vlan-interface 70
ip address 10.181.70.2 24
bfd min-tx-interval 500
bfd min-rx-interval 500
ip route-static 10.181.56.0 255.255.255.0 vlan-interface 70 10.181.70.1 bfd control-packet
ip route-static 10.181.56.0 255.255.255.0 10.181.81.1 preference 100
Root Cause
Static routes cannot detect link faults. When the primary link fails, the route of lower priority cannot take effect. To trigger route switching, bind the BFD session to the primary link and uses the BFD session to detect primary link faults.

Solution

Suggestions
Even after dual static routes are configured between the S9700 and a non-Huawei device, the static routes cannot detect route faults when the primary link fails. You need to configure BFD for static routes so the BFD session can detect faults and trigger route switching accordingly.

END