The log format is as follows:

<Date> <Time> <LoadMaster host name> Removing RS <Real server IP:port> from VS <VS name> - <reason>

Examples of log messages for common health check issues and explanations for these logs are provided below.

Connection Failed - unreachable host 

2023-03-01T12:05::00+00:00 lb100 l4d: Removing RS 192.168.10.20:443 from VS 192.168.10.10:443(HTTPS) - Connection Failed - unreachable host

There is no route to the host.

Timeout waiting for connection 

2023-03-01T12:05::00+00:00 lb100 l4d: Removing RS 192.168.10.20:443 from VS 192.168.10.10:443(HTTPS) - Timeout waiting for connection

Three-way handshake (SYN, SYN-ACK, ACK) did not complete successfully.

Timeout waiting for data 

2023-03-01T12:05::00+00:00 lb100 l4d: Removing RS 192.168.10.20:443 from VS 192.168.10.10:443(HTTPS) - Timeout waiting for data

Three-way handshake (SYN, SYN-ACK, ACK) completed successfully, a request was sent to the Real Server but the LoadMaster did not receive a reply.