Freqency of Alerts

Well that would depend on your setup and policies. Generally I wouldn't suggest making a global change just for a few servers, but if your whole setup is only those servers then I guess that is fine. I would suggest looking at the other various options to see if there are other options. For example if it's expected that the disk space will be high due to overnight backups, you may want to set time-based thresholds or even a reoccuring SDT for that period. Or if the alert is flapping a lot, perhaps setting the number of times it checks before it alerts (rather then how frequently) might work better. Keep in mind that setting it to 6hr might delay alerts, but it can also delay clearing them.

Also note that you can set the polling interval at the device/group level: https://www.logicmonitor.com/support/logicmodules/datasources/creating-managing-datasources/creating-datasources#h-collection-interval .