Support
Knowledge Base
Product followed successfully.

Failed to follow the product.

FAQ: Why Do VPNv4 Routes Disappear After the NE80 Is Upgraded to V300R005?

Publication Date: 2013-09-03 Views: 99 Downloads: 0

Issue Description

The NE80 functions as the core P device and a reflector on a carrier DCN. After the NE80 is upgraded to V300R005, no VPNv4 route exists and PE devices connected to the NE80 cannot receive routes reflected by the NE80. However, before the NE80 upgrade, the PE devices can receive the routes. Why do VPNv4 routes disappear after the NE80 upgrade?

NE80 source version: V100R002B03D051SP02
NE80 target version: V300R005C01B323SPC003+SPH019

Handling Process

Check the NE80 before and after the upgrade. The NE80 of the later version detects the route target (RT) value while the NE80 of the earlier version does not. PE devices are configured with VPN and therefore are not affected by the RT value. The P device that is not configured with VPN cannot identify the RT value and therefore does not process VPNv4 routes. If the P device also functions as a reflector, the P device does not reflect VPNv4 routes.

Root Cause

The NE80 of the later version detects the RT value while the NE80 of the earlier version does not. PE devices are configured with VPN and therefore are not affected by the RT value. The P device that is not configured with VPN cannot identify the RT value and therefore does not process VPNv4 routes. If the P device also functions as a reflector, the P device does not reflect VPNv4 routes.

Solution

Disable the RT function in the BGP VPNv4 view. The problem is solved.
[huawei-bgp-af-vpnv4]un policy vpn-target

Suggestions

1. Check whether the preceding scenario exists before the upgrade. If the preceding scenario exists, disable RT detection. Otherwise, services are affected.
2. If there are many reflectors, the problem may be shielded. After the link is disconnected or the device is upgrade, the problem may occur.

END