When ServiceNow is Integrated with Slack using Now Actions only 1000 channels are getting imported even though there are more channels and which Job syn's those channels as soon as slack is integrated with ServiceNow

Madrid, NY, Orlando

There is a limitation from Slack API with channel sync number

There is a limitation in initial sync up to 1000 channels only.

There is no direct fetch option to get remaining channels from Slack, but what we observed in a few cases is those channels will also get sync gradually by multiple "Messaging Channel Sync" Job runs.

In this below documentation if you go to Pagination it explains that the limit is 1000

https://api.slack.com/methods/channels.list.

There is a warning that this API is getting deprecated so we are working internally on other API where we can use Pagination and sync more than 1000 channels

And regarding setting the channel to false is done only when the channel in slack is Archived other than that we don't have any other way to set the channel in ServiceNow to false

For each "Messaging Channel Sync" Job, we log the response as well in system logs.

There is no BR/Script we use to set the channel to active=false and that was done automatically.

While using the channel.list API, what we pass right now is only bot token, and the rest of the parameters are by default (Slack Default value if something is not being passed). What you are observing is an issue if Slack has more than 1000 channels and API call returns slack channel to the instance which might not have been initially and due to certain logic is set as inactive.

"Messaging Channel Sync" is the job that runs and sync channels, but the channels received in the instance from slack might not be the same channels that would have been received before. 

We can see Payload for inbound channels in table "messaging_inbound"

Right now, we do not have any workaround for that in NY / Orlando / Paris unless you can set the flag manually. In Quebec, which will use the new API conversation.list along with that we would be implementing Pagination to avoid such issues which you are seeing right now with Limitations and Activations of channels in ServiceNow