Run frozen nodes for historical queries

​

How freeze mode works

• Query endpoints stay up: the Tendermint RPC, the REST API, gRPC, and the EVM JSON-RPC.
• Transaction and evidence submission fail with RPC writes are disabled in freeze mode. This includes eth_sendRawTransaction.
• Mempool gossip is off.
• State sync is off. If it is enabled in config.toml, the node logs a notice and uses block sync.
• Block sync and consensus stop before freeze-height and do not advance.

​

Freeze heights

curl -s https://rest.sei-apis.com/cosmos/upgrade/v1beta1/applied_plan/v6.7 | jq -r .height
# 236450000

seid query upgrade plan

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Before you begin

• A full node. Freeze mode does not run in validator or seed mode.
• A copy of a node’s data directory that is below the freeze height. The node refuses to start if its application, block store, or state store has reached freeze-height.
• The history that you want to serve. A frozen node serves only what its data directory holds. To serve the full history, copy an archive node.
• Disk space for a full copy of that data. The copy stops growing when it reaches the freeze height.
• Peers that store the blocks from the copy’s height up to the freeze height. The node fetches these blocks with block sync before it freezes. Pruned nodes delete old blocks, so for a copy far below the freeze height, list archive nodes in persistent-peers in config.toml.

​

Set up a frozen node

sudo systemctl stop seid
rsync -a --exclude config/priv_validator_key.json $HOME/.sei/ <user>@<frozen-host>:.sei/
sudo systemctl start seid

rm -f $HOME/.sei/config/node_key.json $HOME/.sei/config/priv_validator_key.json

VERSION=v6.6.4
FILE=sei-chain_${VERSION#v}_linux_x86_64.tar.gz

curl -fLO https://github.com/sei-protocol/sei-chain/releases/download/${VERSION}/${FILE}
curl -fLO https://github.com/sei-protocol/sei-chain/releases/download/${VERSION}/checksums.txt
sha256sum -c checksums.txt --ignore-missing \
  && tar -xzf ${FILE} seid \
  && sudo install -m 0755 seid /usr/local/bin/seid

git clone https://github.com/sei-protocol/sei-chain.git
cd sei-chain
git checkout v6.6.4
make install

seid version
# v6.6.4

mode = "full"

###############################################################################
###                           Base Configuration                            ###
###############################################################################

# minimum-gas-prices and the other base settings above stay as they are.

halt-height = 0

# FreezeHeight contains the first block height a full node must not execute.
# Query RPC remains available, while transaction and evidence submission,
# mempool gossip, and state sync are disabled from startup.
freeze-height = 236450000  # Sei Mainnet v6.7 upgrade height

halt-time = 0

# inter-block-cache and the other base settings below stay as they are.

###############################################################################
###                        State Sync Configuration                         ###
###############################################################################

[state-sync]

sudo tee /etc/systemd/system/seid.service > /dev/null << EOF
[Unit]
Description=Sei frozen node
After=network-online.target

[Service]
User=$USER
ExecStart=$(which seid) start
Restart=always
RestartSec=3
LimitNOFILE=65535

[Install]
WantedBy=multi-user.target
EOF

sudo systemctl daemon-reload
sudo systemctl enable seid

sudo systemctl start seid
sudo journalctl -fu seid

curl -s http://localhost:26657/status | jq -r .sync_info.latest_block_height
# 236449999

curl -s -X POST http://localhost:8545 -H 'Content-Type: application/json' \
  --data '{"jsonrpc":"2.0","id":1,"method":"eth_blockNumber","params":[]}'
# {"jsonrpc":"2.0","id":1,"result":"0xe17f0cf"}

​

Route queries by block height

git clone https://github.com/sei-protocol/sei-chain.git
cd sei-chain
git checkout <release-tag>
make build-frozen-rpc-router

./build/frozen-rpc-router \
  --listen-address 127.0.0.1:8545 \
  --live-node localhost:9545 \
  --frozen-node 236450000=10.0.0.12:8545

curl -s -o /dev/null -D - -X POST http://127.0.0.1:8545 \
  -H 'Content-Type: application/json' \
  --data '{"jsonrpc":"2.0","id":1,"method":"eth_getBlockByNumber","params":["0xe17f0cf",false]}' \
  | grep -i sei-rpc-route
# Sei-Rpc-Route: frozen:236450000

• The router handles only EVM JSON-RPC over HTTP. For the Tendermint RPC, the REST API, or gRPC at old heights, query the frozen node directly.
• Requests without a block number go to the live node. This includes lookups by block or transaction hash, such as eth_getTransactionReceipt.
• WebSocket clients must connect to the live node directly.
• An eth_getLogs or eth_feeHistory range must stay within one interval. A range that crosses a freeze height fails with JSON-RPC error -32000.
• The router has no authentication. Bind it to 127.0.0.1, or put it behind a firewall or reverse proxy.

​

Prepare for each upgrade

1. When an upgrade proposal passes, read its height with seid query upgrade plan.
2. Before the chain reaches that height, set up a frozen node on the latest patch of the current release, with freeze-height set to the upgrade height.
3. After the new frozen node reaches its boundary, back it up and add it to the router with one more --frozen-node flag.