All online services from the National Library of Ireland, including the free Roman Catholic Registers database of images at nli.registers.ie, are currently offline.
I'm not sure what the problem is, but the Library's tech team is aware of it, so hopefully it won't be too long before normal service is returned.
UPDATE - 1pm: It seems the Library has suffered a 'prolonged power outage'. In addition to the on-going loss of online services, all the Library's buildings have been closed and will remain so throughout the day. So no access to exhibitions, Reading Rooms, Cafe Joly, or the free Genealogy Advisory Service.
UPDATE - 7pm: The Library's web services – both the main site (http://www.nli.ie) and the RC Registers database (http://registers.nli.ie/) – are back with us online.
UPDATE, 15 September: The NLI has announced that its online services will be offline this evening from 5pm to 10pm for 'essential electrical works'. Whether this is related to the power cut earlier in the week, I don't know.