TCP connection on the L2 VPN between NSX for vSphere Edge and Standalone edge disconnects after 1 hour.

Products

• VMware NSX Data Center for vSphere

Issue/Introduction

With the L2 VPN configuration between NSX for vSphere Edge and Standalone Edge, following situation may be observed.
- TCP connection is dropped after 3600 secs since the last traffic.
- Following information is recorded in Standalone Edge log.
kernel: nf_conntrack: TCP Connection Timedout

Environment

VMware NSX Data Center for vSphere 6.4.x
VMware NSX for vSphere 6.2.x
VMware NSX for vSphere 6.3.x

Resolution

It is an expected behavior where the Standalone Edge disconnects every TCP connection on L2 VPN tunnel after 3600 secs (Inactivity Timeout) since the last traffic was sent on the tunnel. This timeout value is not configurable.

Additional Information

To workaround the issue, use NSX Edge instead of Standalone Edge. See KB2101275 for changing inactivity timeout in NSX Edge.