Latency through Iron Port Devices

[navydivervet]

  Receiving 4 to 24 seconds latency when Iron Port Devices are source, going outbound to external web destinations. There is no latency when IronPort is the destination. Looking for possible causes or advice on where to look. 

[Mathew Huynh]

Hello Martino,

Are you able to get some message tracking information so we can have a look at which point it may be delayed.

If it's at the DCID connection creation side, or workqueues processing or so.

Generally key delays are due to workqueue processing if the email is very large or there are too many policies, filters etc the email needs to pass before exiting the workqueue.

Or for connection level, the reverse DNS lookup and MX record lookup of the destination domain can cause some issues if DNS is not responding quick enough.

Finally TLS negotiation if there is some form of SMTP inspection at firewall levels.

Thanks,

Matthew