Configure DNS MX Resolution
DNS MX Resolution may be enabled, configured or disabled by manually editing the Mail Connector’s active .xml configuration file. The feature is off by default.
To turn it on and/or set its cache-update interval:
1. Use an XML editor to open the active configuration file.
2. To enable DNS MX Resolution:
a) Find the <resolvemx> parameter, in the <root> node. If the <resolvemx> parameter does not already exist, create it as shown in the next step below.
b) Set the <resolvemx> parameter value to true: <resolvemx>true</resolvemx>
If the tags are omitted from the file, the feature is disabled. If the tags appear in the file but are left empty (no value), the feature is enabled.
3. To set the cache-update interval for the DNS MX Resolution feature:
a) Find the <mxcacheupdateinterval> parameter, in the <root> node. If the <mxcacheupdateinterval> parameter does not already exist, create it as shown in the next step.
b) Set the <mxcacheupdateinterval> parameter value to the number of seconds you want MX lookups to be cached: <mxcacheupdateinterval>600</mxcacheupdateinterval>
The default (if unspecified) is 300 seconds (5 mins). You may want to increase the value to reduce the load on the DNS server and/or the network. You may want to decrease the value if you want change to take effect faster or to allow for round-robin resolution.
This feature is applied separately per host. (For example, if server A is resolved at 12:00PM, it will be cached until 12:05, while if server B is resolved at at 12:01PM, it will be cached until 12:06, and so forth. There is no setting that causes all hosts to expire at the same time.
4. Close and Save the configuration file under the same filename. The new settings will take effect the next time the Coexistence Manager for Notes (CMN) service is restarted.