To replace a GitHub Enterprise Server node, you must mark the affected nodes offline in the cluster configuration file (cluster.conf) and add the replacement nodes. This might be necessary if a node were to fail, or to add a node with more resources to increase performance.
A GitHub Enterprise Server cluster is comprised of redundant services that are distributed across two or more nodes. If an individual service or an entire node were to fail, it should not be immediately apparent to users of the cluster. However since performance and redundancy are affected, it is important to monitor the health of a GitHub Enterprise Server cluster.