Level 5 is now in place nationwide in an effort to stop the spread of Covid-19.
It comes as the national 14-day incidence rate per 100,000 is now 291 - while Cavan's is in excess of 1,000.
The restrictions will be in place for six weeks - with people not allowed to travel five kilometres from their home apart from specific reasons.
All non-essential retail is closed, pubs, restaurants, and cafes are take-away only but schools, creches, and construction are staying open.
The Taoiseach hopes the measures will allow people to celebrate Christmas in a 'meaningful way'.
Gardaí will introduce more checkpoints from today as part of the Level 5 restrictions.
Training in the Garda College in Templemore will also stop so recruits can be released to help with frontline duties
The extension of Operation Fanacht will see Gardai continue their policy of policing by consent with enforcement only being used as a last resort.
They'll also be available for vulnerable people in the community who may need extra assistance during the increased restrictions.