How to disable alerts on individual instance-discovered DCI's?

[Millenium7]

Almost all DCI's I have added by templates and/or by instance discovery scripts
Some of these I want to disable alerts (or entirely disable monitoring, but just disabling alerts is better) because of getting false positives
One of these is Rx FCS errors on any ports going from a MikroTik to a Cambium PTP device, always generates a false FCS every 30/60/90 seconds so I want to stop it

I've tried 3 things here and none of them work

• Go to properties of DCI on node, thresholds tab, add > -999 and click edit on threshold event then just click ok so it says <none>. This should disable alert and it does, but it gets overridden overnight and this threshold disappears
• Right click on DCI on node and choose disable. Next day its enabled again
• Go to alarms page of node and sticky acknowledge the alarm. Doesn't seem to matter, I'm still getting SLACK alerts (sent by event processing policy for that event/alarm)

How do I fix this? I need to exclude some DCI's on an individual basis
Ideally I want a clean and simple method.
Method #1 is the best so far because I can see the ? symbol on the 'last values' page of a node so I know that I have manually disabled alerting on that DCI (not really, but the ? symbol will always be active because the first threshold is always reached, and just doesn't do anything). That way if I move a device later on to a different port I can see to re-enable it
Method #3 is not so good because it leaves the alarm symbol on the icon of the node while the alarm is still there
But none of the above work anyway so I need something different

[Filipp Sudanov]

Current approach to templates in NetXMS has the idea, that all nodes, belonging to one template are absolutely the same.

You could create a separate template for your exclusion cases and set up template autoapply scripts that would set correct template for a particular node.

The other way could be to use the following syntax in threshold field %{custom_attribute_name:100} in template. In this case threshold value will be taken from a custom attribute, specified on a node and if such attribute is not present on a node, a default value of 100 will be used.