There are four SMTP nodes, mapped to a virtual server. When bulk mails (up to 1 million) are routed through the F5/virtual server, the latency is high and takes forever to process. On a direct connection to one of the SMTP nodes, the throughput is much better. This has been going on for over a year and is most noticed at month end when the bank needs to send bulk mails to her customers.
What could be causing this problem
How many SMTP request can the F5 BIG-IP process per second