Connectivity loss with IPv6 configured ESG when high availability failover occurs

Products

• VMware NSX Networking

Issue/Introduction

Symptoms:

• Edge Services Gateway is configured in high availability mode.
• ESG is configured with IPv6 addresses on interfaces.
• When High Availability failover event occurs, ESG loss connectivity.
• During an Edge high availability failover event, you see entries on the active edge node(formar standby node) similar to:

2017-05-09T15:37:45+00:00 vShield-edge-78-0 config: [daemon.err] ERROR :: C_UTILS :: /usr/sbin/ndsend -r fc00:X:X:XXX::XX:XXX vNic_1: [256] failed to send neighbor advertisement : ndsend sends an unsolicited Neighbor Advertisement ICMPv6 multicast packet
2017-05-09T15:37:45+00:00 vShield-edge-78-0 announcing [user.notice] a given IPv6 address to all IPv6 nodes as per RFC4861.
2017-05-09T15:37:45+00:00 vShield-edge-78-0 Usage: [user.notice] ndsend <address> <interface> (example: ndsend 2001:DB8::1 eth0)
2017-05-09T15:37:45+00:00 vShield-edge-78-0 Note: [user.notice] ndsend is called by arpsend -U -i, see arpsend(8) man page.
2017-05-09T15:37:45+00:00 vShield-edge-78-0 [user.notice]

Environment

VMware NSX for vSphere 6.1.x
VMware NSX for vSphere 6.0.x
VMware NSX for vSphere 6.2.x
VMware NSX for vSphere 6.3.x
VMware NSX for vSphere 6.4.x

Cause

This issue occurs when the physical switch is not updated with the current location of the active edge appliance and keeps sending traffic to the standby appliance until ARP cache times out causing traffic to be blocked and directed to a standby appliance.

Resolution

This issue is resolved in VMware NSX for vSphere 6.4.0, available at VMware Downloads.

Workaround:
To work around this issue if you do not want to upgrade, remove and re-add IPv6 address on an interface.