# Replace More Than One Dead Node In A ScyllaDB Cluster

#### NOTE
Replacing a node requires at least a quorum of nodes in a cluster to be available.
If the quorum is lost, it must be restored before a node is replaced.
See [Handling Node Failures](https://docs.scylladb.com/manual/master/troubleshooting/handling-node-failures.md) for details.

## Prerequisites

* Updating the cluster topology requires at least a quorum of nodes in a cluster to be available.
  If the quorum is lost, it must be restored before you change the cluster topology.
  See [Handling Node Failures](https://docs.scylladb.com/manual/master/troubleshooting/handling-node-failures.md) for details.

  You can check the status of the nodes in the cluster using the [nodetool status](https://docs.scylladb.com/manual/master/operating-scylla/nodetool-commands/status.md) command.
* Verify the status of the cluster using [nodetool status](https://docs.scylladb.com/manual/master/operating-scylla/nodetool-commands/status.md) command. A node with status `DN` is down and needs to be replaced.

```shell
Datacenter: DC1
Status=Up/Down
State=Normal/Leaving/Joining/Moving
--  Address        Load       Tokens  Owns (effective)                         Host ID         Rack
UN  192.168.1.201  112.82 KB  256     32.7%             8d5ed9f4-7764-4dbd-bad8-43fddce94b7c   B1
DN  192.168.1.202  91.11 KB   256     32.9%             125ed9f4-7777-1dbn-mac8-43fddce9123e   B1
DN  192.168.1.203  124.42 KB  256     32.6%             675ed9f4-6564-6dbd-ca08-43fddce952de   B1
```

Login to one of the nodes in the cluster with (UN) status, collect the following info from the node:

* cluster_name - `cat /etc/scylla/scylla.yaml | grep cluster_name`
* seeds - `cat /etc/scylla/scylla.yaml | grep seeds:`
* endpoint_snitch - `cat /etc/scylla/scylla.yaml | grep endpoint_snitch`
* ScyllaDB version - `scylla --version`

## Procedure

Depend on the Replication Factor (RF)

* If the number of failed nodes is smaller than your keyspaces RF, you still have at least one available replica with your data, and you can use [Replace a Dead Node](https://docs.scylladb.com/manual/master/operating-scylla/procedures/cluster-management/replace-dead-node.md) procedure.
* If the number of failed nodes is equal or larger than your keyspaces RF, then some of the data is lost, and you need to retrieve it from backup. Use the [Replace a Dead Node](https://docs.scylladb.com/manual/master/operating-scylla/procedures/cluster-management/replace-dead-node.md) procedure and [restore the data from backup](https://docs.scylladb.com/manual/master/operating-scylla/procedures/backup-restore/restore.md).