How do I start Electrs with signet-magic option?

I am playing around with creating a custom signet and was hoping to be able to use Umbrel as a teaching tool with this custom signet.

I was able to make the Bitcoin Node app use this custom signet by providing the signetchallenge= configuration line in ~/umbrel/app-data/bitcoin/data/bitcoin/bitcoin.conf file. Consequently, the Lightning Node and RTL apps both worked with this custom signet without needing any configuration changes.

However, the Electrs app is not working, due to the default signet-magic option being different than the one my custom signet is using.

In my own barebones setup (not Umbrel), I used the original romanz/electrs and started it up by providing the --signet-magic option when calling the electrs binary.

My question is, how do I do this in Umbrel’s Electrs app? Any help will be greatly appreciated. Thanks.

~/umbrel/app-data/electrs/docker-compose.yml

Add the environment variable ELECTRS_SIGNET_MAGIC to this file.

Example)
environment:.
ELECTRS_LOG_FILTERS: β€œINFO”
ELECTRS_NETWORK: β€œ${APP_BITCOIN_NETWORK_ELECTRS}”
ELECTRS_DAEMON_RPC_ADDR: β€œ${APP_BITCOIN_NODE_IP}:${APP_BITCOIN_RPC_PORT}”
ELECTRS_DAEMON_P2P_ADDR: β€œ${APP_BITCOIN_NODE_IP}:${APP_BITCOIN_P2P_PORT}”
ELECTRS_ELECTRUM_RPC_ADDR: β€œ0.0.0.0:${APP_ELECTRS_NODE_PORT}”
ELECTRS_SERVER_BANNER: β€œUmbrel Electrs (${APP_VERSION})”
ELECTRS_DB_DIR: β€œ/data/db”
ELECTRS_SIGNET_MAGIC: β€œ3f7c212f”

1 Like

Thank you! This worked! And now the Mempool app that is dependent on Electrs is also working. Thank you so much!