Mirror Nodes

Store history and cost-effectively query data

Mirror nodes provide a way to store and cost-effectively query historical data from the public ledger while minimizing the use of Hedera network resources. Mirror nodes support the Hedera network services currently available and can be used to retrieve the following information:

• Transactions and records

• Event files

• Balance files

Understanding Mirror Nodes

Hedera Mirror Nodes receive information from Hedera network consensus nodes, either mainnet or testnet, and provide a more effective means to perform:

• Queries

• Analytics

• Audit support

• Monitoring

While mirror nodes receive information from the consensus nodes, they do not contribute to consensus themselves. The trust of Hedera is derived based on the consensus reached by the consensus nodes. That trust is transferred to the mirror nodes using signatures, chain of hashes, and state proofs.

To make the initial deployments easier, the mirror nodes strive to take away the burden of running a full Hedera node through the creation of periodic files that contain processed information (such as account balances or transaction records) and have the full trust of the Hedera consensus nodes. The mirror node software reduces the processing burden by receiving pre-constructed files from the network, validating those, populating a database, and providing REST APIs.

Mirror nodes work by validating the signature files associated with the record, balance, and event files from the consensus nodes that were uploaded to a cloud storage solution from the network.

As transactions reach consensus on the Hedera network, either mainnet or testnet, Hedera consensus nodes add the transaction and its associated records to a record file. A record file contains a series of ordered transactions and their associated records. After a given amount of time, a record file is closed and a new one is created. This process repeats as the network continues to receive transactions.

Once a record file is closed, the consensus nodes generate a signature file. The signature file contains a signature for the corresponding record file’s hash. Along with the signature file of the consensus node, the record file also contains the hash of the previous record file. The former record file can now be verified by matching the hash of the previous record file.

Hedera consensus nodes push new record files and signature files to the cloud storage provider – currently AWS S3 and Google File Storage are supported. Mirror nodes download these files, verify their signatures based on their hashes, and only then make them available to be processed.

REST API from Hedera

Hedera provides REST APIs to easily query a mirror node that is hosted by Hedera, removing the complexity of having to run your own. Check out the mirror node REST API docs below.

REST API

Run a Mirror Node

Anyone can run a Hedera Mirror Node by downloading and configuring the software on their computer. By running a mirror node, you are able to connect to the appropriate cloud storage and store account balance files, record files, and event files as described above. Please check out the below links on how to get started.

Run Your Own Mirror NodeOne Click Mirror Node Deployment

Minimum Hardware Requirements & Associated Costs

To run a Hedera Mirror Node, you'll need specific hardware and resources. The recommended minimum requirements for running a Mirror Node, along with the associated costs, are outlined below.

Compute Engine

• Region: Iowa

• Provisioning Model: Regular

• Instance Type: n1-standard-4

• Operating System / Software: Free

• Total hours per month: 1,460

• Sustained Use Discount: Applied (30%)

The estimated cost for the compute engine per month is USD 194.18.

Cloud SQL for PostgreSQL

• Instance Type: db-highmem-4

• Location: Iowa

• Number of Instances: 1

• Total hours per month: 730.0

• SSD Storage: 200.0 GiB

• Backup: 200.0 GiB

The estimated cost for Cloud SQL for PostgreSQL per month is USD 303.46.

Persistent Disk (Accompanying)

• Product accompanying: GKE Standard

• Zonal SSD PD: 50 GiB (2 x boot disk)

The estimated cost for the persistent disk per month is USD 17.00.

Based on these specifications, the total estimated cost to run a Hedera Mirror Node per month is USD 514.64.

Please note: these are estimated costs and actual costs may vary depending on usage and any changes to the pricing of the resources used. Always refer to the most recent price lists from the respective services for accurate costs.

Lastly, this setup offers a good balance between cost and performance but you may need to adjust these specifications based on the specific needs and workload of your Mirror Node.