Our outbound accounts have long been configurable with one IPv4 and one IPv6 address or host name lookup (A or AAAA). A couple weeks ago a situation was brought to our attention that caused a conflict: end sites with a different failover IP. In order for these sites to work, you’d have to log in and change the filter to the failover IP and then back again later to the primary IP.
To fix this we have just released a new addition of an alternate IP filter setting for both IPv4 and IPv6 addresses.
This setting works in conjunction with the original primary filter setting to specifically resolve the issue of business customer sites with a failover circuit, and is available on accounts with a service level of Standard and above.