All pipeline failed in the datahub

Product/components used and version/fix level:

Detailed explanation of the problem:

All the datahub pipeline has failed and its giving the error message below since 2 days ago.

Error messages / full error message screenshot / log file:

Invalid Query Exception. Validation of view sql failed. The source [c8y_source] is currently unavailable. Metadata is not accessible; please check node health (or external storage) and permissions. Info: [Source ‘c8y_source’ returned error ‘Connection to Mongo failed. No collections were visible.’]

Question related to a free trial, or to a production (customer) instance?

Production