A Geth node continually reports messages to the console allowing users to monitor Geth's current status in real-time. The logs indicate when Geth is running normally and indicates when some attention is required. However, reading these logs can be difficult for new users. This page will help to interpret the log messages to better understand what Geth is doing.
Note that there are a large number of log messages covering a wide range of possible scenarios for a Geth node. This page will only address a subset of commonly seen messages. For more, see the [Geth GitHub](https://github.com/ethereum/go-ethereum), [Discord](https://discord.gg/WHNkYDsAKU) or search on [ethereum.stackexchange](https://ethereum.stackexchange.com/). Log messages are usually sufficiently self-describing that they do not require additional explanation.
Log messages are displayed to the console by default. The messages can be tuned to be more or less detailed by passing `--verbosity` and a value between 0 and 5 to Geth at startup:
Log messages can also be redirected so they are saved to a text file instead of being displayed in the console. In Linux the syntax `>> <path> 2>&1` redirects both `stdout` and `stderr` messages to `<path>`. For example:
When Geth starts up it immediately reports a fairly long page of configuration details and status reports that allow the user to confirm Geth is on the right network and operating in its intended modes. The basic structure of a log message is as follows:
Where `MESSAGE_TYPE` can be `INFO`, `WARN`, `ERROR` or `DEBUG`. These tags categorize log messages according to their purpose. `INFO` messages inform the user about Geth's current configuration and status. `WARN` messages are for alerting the user to details that affect the way Geth is running. `ERROR` messages are for alerting the user to problems. `DEBUG` is for messages that are relevant to troubleshooting or for developers working on Geth.
The logs above show the user that the node is connecting to Ethereum Mainnet and some low level configuration details. The cache size is bumped to the Mainnet default (4096). The maximum peer count is the highest number of peers this node is allowed to connect to and can be used to control the bandwidth requirements of the node. Logs relating to `ethash` are out of date since Ethereum moved to proof-of-stake based consensus and can safely be ignored.
INFO [10-04|10:20:52.387] - Gray Glacier: 15050000 (https://github.com/ethereum/execution-specs/blob/master/network-upgrades/mainnet-upgrades/gray-glacier.md)
```
The above block of messages are related to past Ethereum hard forks. The names are the names of the hard forks and the numbers are the blocks at which the hard fork occurs. This means that blocks with numbers that exceed these values have the configuration required by that hard fork. The specification of each hard fork is available at the provided links (and more information is available on [ethereum.org](https://ethereum.org/en/history/)). The message `Consensus: Beacon (proof-of-stake), merged from Ethash (proof-of-work)` indicates that the node requires a Beacon node to follow the canonical chain - Geth cannot participate in consensus on its own.
The messages above relate to [The Merge](https://ethereum.org/en/upgrades/merge/). The Merge was Ethereum's transition from proof-of-work to proof-of-stake based consensus. In Geth, The Merge came in the form of the Paris hard fork which was triggered at a [terminal total difficulty](https://ethereum.org/en/glossary/#terminal-total-difficulty) of 58750000000000000000000 instead of a preconfigured block number like previous hard forks. The hard fork specification is linked in the log message. The message `network known to be merged: true` indicates that the node is following a chain that has passed the terminal total difficulty and undergone the Paris hard fork. Since September 15 2022 this will always be true for nodes on Ethereum Mainnet (and the merged testnets Sepolia and Goerli). The warning `Engine API enabled` informs the user that Geth is exposing the set of API methods required for communication with a consensus client.
INFO [10-04|10:20:52.389] Starting peer-to-peer node instance=Geth/v1.11.0-unstable-e004e7d2-20220926/linux-amd64/go1.19.1
INFO [10-04|10:20:52.409] New local node record seq=1,664,875,252,408 id=9aa0e5b14ccd75ec ip=127.0.0.1 udp=30303 tcp=30303
INFO [10-04|10:20:52.409] Started P2P networking self=enode://1ef45ab610c2893b70483bf1791b550e5a93763058b0abf7c6d9e6201e07212d61c4896d64de07342c9df734650e3b40812c2dc01f894b6c385acd180ed30fc8@127.0.0.1:30303
INFO [10-04|10:20:52.410] IPC endpoint opened url=/home/go-ethereum/devnet/geth.ipc
INFO [10-04|10:20:52.410] Generated JWT secret path=/home/go-ethereum/devnet/geth/jwtsecret
INFO [10-04|10:20:52.411] HTTP server started endpoint=127.0.0.1:8545 auth=false prefix= cors= vhosts=localhost
INFO [10-04|10:20:52.411] WebSocket enabled url=ws://127.0.0.1:8551
INFO [10-04|10:20:52.411] HTTP server started endpoint=127.0.0.1:8551 auth=true prefix= cors=localhost vhosts=localhost
INFO [10-04|10:20:54.785] New local node record seq=1,664,875,252,409 id=9aa0e5b14ccd75ec ip=82.11.59.221 udp=30303 tcp=30303
INFO [10-04|10:20:55.267] Mapped network port proto=udp extport=30303 intport=30303 interface="UPNP IGDv1-IP1"
INFO [10-04|10:20:55.833] Mapped network port proto=tcp extport=30303 intport=30303 interface="UPNP IGDv1-IP1"
INFO [10-04|10:21:03.100] Looking for peers peercount=0 tried=20 static=0
```
The logs above relate to Geth starting up its peer-to-peer components and seeking other nodes to connect to. The long address reported to `Started P2P networking` is the nodes own enode address. The `IPC Endpoint` is the location of the node's IPC file that can be used to connect a Javascript console. There is a log message confirming that a JWT secret was generated and reporting its path. This is required to authenticate communication between Geth and the consensus client. There are also messages here reporting on the HTTP server that can be used to send requests to Geth. There should be two HTTP servers - one for interacting with Geth (defaults to `localhost:8545`) and one for communication with the consensus client (defaults to `localhost:8551`).
The default for Geth is to sync in snap mode. This requires a block header to be provided to Geth by the consensus client. The header is then used as a target to sync to. Geth requests block headers from its peers that are parents of the target until there is a continuous chain of sequential headers of sufficient length. Then, Geth requests block bodies and receipts for each header and simultaneously starts downloading state data. This state data is stored in the form of a [Patricia Merkle Trie](https://ethereum.org/en/developers/docs/data-structures-and-encoding/patricia-merkle-trie/). Only the leaves of the trie are downloaded, the full trie structure is then locally regenerated from the leaves up. Meanwhile, the blockchain continues to progress and the target header is updated. This means some of the regenerated state data need to be updated. This is known as _healing_.
Assuming Geth has a synced consensus client and some peers it will start importing headers, block bodies and receipts. The log messages for data downloading look as follows:
For state sync, Geth reports when the state heal is in progress. This can take a long time. The log message includes values for the number of `accounts`, `slots`, `codes` and `nodes` that were downloaded in the current healing phase, and the pending field is the number of state entries waiting to be downloaded. The `pending` value is not necessarily the number of state entries remaining until the healing is finished. As the blockchain progresses the state trie is updated and therefore the data that need to be downloaded to heal the trie can increase as well as decrease over time. Ultimately, the state should heal faster than the blockchain progresses so the node can get in sync. When the state healing is finished there is a post-sync snapshot generation phase. The node is not in sync until the state healing phase is over. If the node is still regularly reporting `State heal in progress` it is not yet in sync - the state healing is still ongoing.
INFO [07-28|10:30:21.965] State heal in progress accounts=169,633@7.48MiB slots=57314@4.17MiB codes=4895@38.14MiB nodes=43,293,196@11.70GiB pending=112,626
The sync can be confirmed using [`eth.syncing`](https://ethereum.org/en/developers/docs/apis/json-rpc/#eth_syncing) - it will return `false` if the node is in sync. If `eth.syncing` returns anything other than `false` it has not finished syncing. Generally, if syncing is still ongoing, `eth.syncing` will return block info that looks as follows:
This warning is nothing to worry about - it is reporting a configuration mismatch between the node and a peer. It does not mean syncing is stalling or failing, it simply results in the peer being dropped and replaced.
The message above indicates that the fork choice algorithm, which is run by the consensus client, has identified a new target Geth should sync up to. This redirects the sync to prevent syncing to an outdated target and is a natural part of syncing a live blockchain.
Transactions submitted over local IPC, Websockets or HTTP connections are reported in the console logs. For example, a simple ETH transaction appears in the console logs as follows:
There are many warnings that can be emitted by Geth as part of its normal operation. However, some are asked about especially frequently on the [Geth GitHub](https://github.com/ethereum/go-ethereum) and [Discord](https://discord.gg/WHNkYDsAKU) channel.
The above is often seen and misinterpreted as a problem with snap sync. In reality, it indicates a request timeout that may be because I/O speed is low. It is usually not an issue, but if this message is seen very often over prolonged periods of time it might be rooted in a local connectivity or hardware issue.
The above message is emitted when Geth is run without a consensus client on a post-merge proof-of-stake network. Since Ethereum moved to proof-of-stake Geth alone is not enough to follow the chain because the consensus logic is now implemented by a separate piece of software called a consensus client. This log message is displayed when the consensus client is missing. Read more about this on our [consensus clients](/docs/getting-started/consensus-clients) page.
WARN [10-03 |13:10:26.499] Beacon client online, but never received consensus updates. Please ensure your beacon client is operational to follow the chain!
The message above indicates that a consensus client is present but not working correctly. The most likely reason for this is that the client is not yet in sync. Waiting for the consensus client to sync should solve the issue.
This message indicates that a peer is being dropped because it is not fully synced. This is normal - the necessary data will be requested from an alternative peer instead.
There are a wide range of log messages that are emitted while Geth is running. The level of detail in the logs can be configured using the `verbosity` flag at startup. This page has outlined some of the common messages users can expect to see when Geth is run with default verbosity, without attempting to be comprehensive. For more, please see the [Geth GitHub](https://github.com/ethereum/go-ethereum) and [Discord](https://discord.gg/WHNkYDsAKU).
