This figure shows a grid where K-safety is set to 2 with six elements contained within three replica sets: the elements within the host3.instance1 and host4.instance1 data instances are part of a replica set 1; the elements within the host5.instance1 and host6.instance1 data instances are within a replica set 2; the elements within host7. instance1 and host8.instance1 data instances are in a replica set 3. The host3.instance1, host5.instance1, and host7.instance1 data instances are within data space 1; the host4.instance1, host6.instance1 and host8.instance1 data instances are in data space 2. However, since the elements within the host3.instance1 and host4.instance1 data instances have failed and these are both in the same replica set, the entire replica set 1 has failed. All transactions that include data within these replica set 1 is blocked.