You can monitor your NSX-T Data Center environment using vRealize Log Insight.

Information about the NSX-T Log Insightcontent pack:

Name VMware - NSX-T
Version 3.8.2
Author VMware, Inc.
Website https://www.vmware.com
Namespace com.vmware.nsxt
Description The NSX-T Log Insight content pack provides health status dashboards for the logical switching and routing, distributed firewall, and DHCP components that make up the NSX infrastructure. It also provides key audit logs for tracking create, add and delete changes to your NSX infrastructure.

Minimum requirements: Log Insight 3.0

This content pack has the following alerts:

Alert Name Description
SysCpuUsage CPU usage is above 95% for more than 10 minutes.
SysMemUsage Memory usage is above 95% for more than 10 minutes.
SysDiskUsage Disk usage for one or more partitions is above 89% for more than 10 minutes.
PasswordExpiry Password for appliance user account is about to expire or expired.
CertificateExpiry One or more CA signed certificate is expired.
ClusterNodeStatus Local edge cluster node is down.
BackupFailure NSX scheduled backup operation failed.
VipLeadership NSX Management cluster VIP is down.
ApiRateLimit Client API reached configured threshold.
CorfuQuorumLost Two nodes went down in the cluster and lost corfu quorum.
DfwHeapMem DFW heap memory exceeded configured threshold.
ProcessStatus Critical process status changed.
ClusterFailoverStatus SR high availability state changed or active/standby services failover.
DhcpPoolUsageOverloadedEvent DHCP pool reached configured usage threshold.
FabricCryptoStatus Edge crypto mux driver is down for failing Known_Answer_Tests (KAT).
VpnTunnelState VPN tunnel is down.
BfdTunnelStatus BFD Tunnel status changed.
RoutingBgpNeighborStatus BGP neighbor status is down.
VpnL2SessionStatus L2 VPN session is down.
VpnIkeSessionStatus IKE session is down.
RoutingStatus Routing(BGP/BFD) is down.
DnsForwarderStatus DNS forwarder running status is DOWN.
TnConnDown_15min Transport Node connection to a controller/Manager is down for at least 15 minutes.
TnConnDown_5min Transport Node connection to controller/Manager is down for at least 5 minutes.
ServiceDown One or more services are down.
IpNotAvailableInPool There is no IP available in the Pool or reaches configured threshold.
LoadBalancerError NSX Load Balancer Service status is ERROR.
LoadBalancerDown NSX Load Balancer Service status is DOWN.
LoadBalancerVsDown VS status: all pool members are down.
LoadBalancerPoolDown Pool status: all pool members are down.
ProcessCrash Process or daemon crashes in the datapath or other LB process like dispatcher, etc..