Migrate nodes to a new IP network

Use the following instructions to update a node's network configuration while ensuring the consensus protocol continues to work as expected. These instructions apply when using a static configuration through the static-nodes.json file.

The following instructions use a three-node network, A, B, and C, as an example, where Node A is being migrated. You can apply these instructions to any number of migrated nodes on any network with any number of nodes.

caution

Before migrating a node to a new network, create a backup of each node's data directory.

Prerequisites

• GoQuorum installed
• A running Raft network or IBFT network

Raft

Peers with same networking configuration

In this scenario, the migrated node has a new network configuration, but its peers keep the same IP addresses and ports. For example:

• Node A's public IP address and port are changed, and Nodes B and C keep the same public IP addresses and ports.
• Node A migrates from one private sub-network 10.1.X.X to another sub-network 10.2.X.X, but can still connect to Nodes B and C using the same IP addresses as before, by routing across the sub-networks.

Steps

1. Stop Node A.

2. On Node B or C, obtain Node A's Raft ID (GoQuorum Raft node ID in the network):

geth console request

raft.cluster

JSON result

{
    "jsonrpc": "2.0",
    "id": 10,
    "result": [{
        "raftId": 1,
        "nodeId": "<enodeId>",
        ...
    }, ...]
}

In this example Node A's Raft ID is 1.

3. On Node B or C, remove Node A from the network using its Raft ID:

   raft.removePeer(<RAFT-ID>)

4. Update the network configuration in Node A's static-nodes.json file.

   note

   Even if this file isn't specified with --raftjoinexisting, it should be updated to keep in sync with the current cluster configuration.

5. Add Node A back to the Raft network with its new network configuration.

6. The nodes can now connect with their peers, and raft.cluster shows the updated information and network configuration.

Peers need a new networking configuration

In this scenario, the migrated node must update the IP addresses and ports of its peers.

For example, Nodes A, B, and C are in the same private sub-network, and Node A migrates to another sub-network, or to the internet. NAT is used to translate the IP addresses from the public to private sub-network and vice versa, requiring the nodes to use their peers' public IPs.

This requires updating the configuration of Node A to use the public IP addresses of Nodes B and C, and updating the configurations of Nodes B and C to use the public IP address of Node A.

Steps

1. Stop all nodes.

2. Clean the cached Raft data.

   In the data folder of each node, run:

   rm quorum-raft-state raft-*

   This forces Raft to refresh the cluster state based on the latest information in the static-nodes.json without losing any of the blockchain data.

3. Migrate Node A's data to the new location.

4. Update the network configuration in the static-nodes.json file of each node with its peers' accessible IP addresses and ports.

5. Start all nodes. The nodes can now connect with their peers, and raft.cluster shows the updated information and network configuration.

IBFT and QBFT

1. Stop Node A.

2. Update the network configuration in Node A's static-nodes.json file with its peers' accessible IP addresses and ports.

3. Start Node A. The nodes can now connect with their peers, and admin.peers returns the current connections between the nodes.