Notifications communicated by the Controller include Local Notifications, SNMP Traps, Syslog, and email.
Local Notifications
Local notifications are marked by alert action with an alert priority for categorizing the alerts. Though high-severity alerts are more important than medium or low alerts, there is no functional difference between them. The color in the GUI reflects only the severity. The Alert Actions object determines which types of notifications are generated for a new alert. Though this object has the option to disable notifications logged to the internal database through the Only Generate External Alerts check box, it does not explicitly call out these notifications.
SNMP Traps
Alerts can be sent through SNMP traps using SNMP v2c. Multiple trap servers can be defined.
Configuring SNMP traps is solely for sending alerts to an SNMP trap server and not for polling the NSX Advanced Load Balancer SNMP OIDs.
Though traps are sent from the Controller Cluster leader, the leadership role can move to either follower Controller after a failure. So the external SNMP server must be configured to allow traffic from any one of the three Controllers in the cluster, i.e., all three addresses should be in the SNMP server’s allowed-access list. The firewall rules must be configured to allow UDP traffic destined to port 162 on the SNMP trap server from any of the three cluster member’s IP addresses.
Syslog
Syslog messages can be sent to one or more syslog servers. Communication is non-encrypted through UDP, using a customizable port. According to RFC 5426, syslog receivers accept syslog datagrams on port 514 (default) and can also be configured to listen on a different port. Configuring Syslog notifications pushes alerts to syslog servers. It does not export the virtual service logs. The logs can be pulled from an external logging system through the API, or scripted to be pushed from the Controller to a remote log system.
Alert Actions can be configured for sending alerts to administrators through email. These emails are sent directly to administrators or reporting systems that accept email. The Controller must have a valid DNS and a default gateway or route configured, to resolve the destination mail server and properly forward the messages. Information regarding the SMTP server and the sender must be configured in the page before email notifications can be sent.
The timestamp used within the alert notification e-mails will be based on UTC by default. A different timezone to use for these timestamps can be configured in the global email/SMTP settings via the CLI. See Email-SMTP Settings in the NSX Advanced Load BalancerAdministration Guide.
