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diff --git a/contrib/devtools/test_utxo_snapshots.sh b/contrib/devtools/test_utxo_snapshots.sh
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+#!/usr/bin/env bash
+# Demonstrate the creation and usage of UTXO snapshots.
+#
+# A server node starts up, IBDs up to a certain height, then generates a UTXO
+# snapshot at that point.
+#
+# The server then downloads more blocks (to create a diff from the snapshot).
+#
+# We bring a client up, load the UTXO snapshot, and we show the client sync to
+# the "network tip" and then start a background validation of the snapshot it
+# loaded. We see the background validation chainstate removed after validation
+# completes.
+#
+
+export LC_ALL=C
+set -e
+
+BASE_HEIGHT=${1:-30000}
+INCREMENTAL_HEIGHT=20000
+FINAL_HEIGHT=$(($BASE_HEIGHT + $INCREMENTAL_HEIGHT))
+
+SERVER_DATADIR="$(pwd)/utxodemo-data-server-$BASE_HEIGHT"
+CLIENT_DATADIR="$(pwd)/utxodemo-data-client-$BASE_HEIGHT"
+UTXO_DAT_FILE="$(pwd)/utxo.$BASE_HEIGHT.dat"
+
+# Chosen to try to not interfere with any running bitcoind processes.
+SERVER_PORT=8633
+SERVER_RPC_PORT=8632
+
+CLIENT_PORT=8733
+CLIENT_RPC_PORT=8732
+
+SERVER_PORTS="-port=${SERVER_PORT} -rpcport=${SERVER_RPC_PORT}"
+CLIENT_PORTS="-port=${CLIENT_PORT} -rpcport=${CLIENT_RPC_PORT}"
+
+# Ensure the client exercises all indexes to test that snapshot use works
+# properly with indexes.
+ALL_INDEXES="-txindex -coinstatsindex -blockfilterindex=1"
+
+if ! command -v jq >/dev/null ; then
+  echo "This script requires jq to parse JSON RPC output. Please install it."
+  echo "(e.g. sudo apt install jq)"
+  exit 1
+fi
+
+DUMP_OUTPUT="dumptxoutset-output-$BASE_HEIGHT.json"
+
+finish() {
+  echo
+  echo "Killing server and client PIDs ($SERVER_PID, $CLIENT_PID) and cleaning up datadirs"
+  echo
+  rm -f "$UTXO_DAT_FILE" "$DUMP_OUTPUT"
+  rm -rf "$SERVER_DATADIR" "$CLIENT_DATADIR"
+  kill -9 "$SERVER_PID" "$CLIENT_PID"
+}
+
+trap finish EXIT
+
+# Need to specify these to trick client into accepting server as a peer
+# it can IBD from, otherwise the default values prevent IBD from the server node.
+EARLY_IBD_FLAGS="-maxtipage=9223372036854775207 -minimumchainwork=0x00"
+
+server_rpc() {
+  ./src/bitcoin-cli -rpcport=$SERVER_RPC_PORT -datadir="$SERVER_DATADIR" "$@"
+}
+client_rpc() {
+  ./src/bitcoin-cli -rpcport=$CLIENT_RPC_PORT -datadir="$CLIENT_DATADIR" "$@"
+}
+server_sleep_til_boot() {
+  while ! server_rpc ping >/dev/null 2>&1; do sleep 0.1; done
+}
+client_sleep_til_boot() {
+  while ! client_rpc ping >/dev/null 2>&1; do sleep 0.1; done
+}
+
+mkdir -p "$SERVER_DATADIR" "$CLIENT_DATADIR"
+
+echo "Hi, welcome to the assumeutxo demo/test"
+echo
+echo "We're going to"
+echo
+echo "  - start up a 'server' node, sync it via mainnet IBD to height ${BASE_HEIGHT}"
+echo "  - create a UTXO snapshot at that height"
+echo "  - IBD ${INCREMENTAL_HEIGHT} more blocks on top of that"
+echo
+echo "then we'll demonstrate assumeutxo by "
+echo
+echo "  - starting another node (the 'client') and loading the snapshot in"
+echo "    * first you'll have to modify the code slightly (chainparams) and recompile"
+echo "    * don't worry, we'll make it easy"
+echo "  - observing the client sync ${INCREMENTAL_HEIGHT} blocks on top of the snapshot from the server"
+echo "  - observing the client validate the snapshot chain via background IBD"
+echo
+read -p "Press [enter] to continue" _
+
+echo
+echo "-- Starting the demo. You might want to run the two following commands in"
+echo "   separate terminal windows:"
+echo
+echo "   watch -n0.1 tail -n 30 $SERVER_DATADIR/debug.log"
+echo "   watch -n0.1 tail -n 30 $CLIENT_DATADIR/debug.log"
+echo
+read -p "Press [enter] to continue" _
+
+echo
+echo "-- IBDing the blocks (height=$BASE_HEIGHT) required to the server node..."
+./src/bitcoind -logthreadnames=1 $SERVER_PORTS \
+    -datadir="$SERVER_DATADIR" $EARLY_IBD_FLAGS -stopatheight="$BASE_HEIGHT" >/dev/null
+
+echo
+echo "-- Creating snapshot at ~ height $BASE_HEIGHT ($UTXO_DAT_FILE)..."
+sleep 2
+./src/bitcoind -logthreadnames=1 $SERVER_PORTS \
+    -datadir="$SERVER_DATADIR" $EARLY_IBD_FLAGS -connect=0 -listen=0 >/dev/null &
+SERVER_PID="$!"
+
+server_sleep_til_boot
+server_rpc dumptxoutset "$UTXO_DAT_FILE" > "$DUMP_OUTPUT"
+cat "$DUMP_OUTPUT"
+kill -9 "$SERVER_PID"
+
+RPC_BASE_HEIGHT=$(jq -r .base_height < "$DUMP_OUTPUT")
+RPC_AU=$(jq -r .txoutset_hash < "$DUMP_OUTPUT")
+RPC_NCHAINTX=$(jq -r .nchaintx < "$DUMP_OUTPUT")
+RPC_BLOCKHASH=$(jq -r .base_hash < "$DUMP_OUTPUT")
+
+# Wait for server to shutdown...
+while server_rpc ping >/dev/null 2>&1; do sleep 0.1; done
+
+echo
+echo "-- Now: add the following to CMainParams::m_assumeutxo_data"
+echo "   in src/kernel/chainparams.cpp, and recompile:"
+echo
+echo "   {${RPC_BASE_HEIGHT}, AssumeutxoHash{uint256S(\"0x${RPC_AU}\")}, ${RPC_NCHAINTX}, uint256S(\"0x${RPC_BLOCKHASH}\")},"
+echo
+echo
+echo "-- IBDing more blocks to the server node (height=$FINAL_HEIGHT) so there is a diff between snapshot and tip..."
+./src/bitcoind $SERVER_PORTS -logthreadnames=1 -datadir="$SERVER_DATADIR" \
+    $EARLY_IBD_FLAGS -stopatheight="$FINAL_HEIGHT" >/dev/null
+
+echo
+echo "-- Starting the server node to provide blocks to the client node..."
+./src/bitcoind $SERVER_PORTS -logthreadnames=1 -debug=net -datadir="$SERVER_DATADIR" \
+    $EARLY_IBD_FLAGS -connect=0 -listen=1 >/dev/null &
+SERVER_PID="$!"
+server_sleep_til_boot
+
+echo
+echo "-- Okay, what you're about to see is the client starting up and activating the snapshot."
+echo "   I'm going to display the top 14 log lines from the client on top of an RPC called"
+echo "   getchainstates, which is like getblockchaininfo but for both the snapshot and "
+echo "   background validation chainstates."
+echo
+echo "   You're going to first see the snapshot chainstate sync to the server's tip, then"
+echo "   the background IBD chain kicks in to validate up to the base of the snapshot."
+echo
+echo "   Once validation of the snapshot is done, you should see log lines indicating"
+echo "   that we've deleted the background validation chainstate."
+echo
+echo "   Once everything completes, exit the watch command with CTRL+C."
+echo
+read -p "When you're ready for all this, hit [enter]" _
+
+echo
+echo "-- Starting the client node to get headers from the server, then load the snapshot..."
+./src/bitcoind $CLIENT_PORTS $ALL_INDEXES -logthreadnames=1 -datadir="$CLIENT_DATADIR" \
+    -connect=0 -addnode=127.0.0.1:$SERVER_PORT -debug=net $EARLY_IBD_FLAGS >/dev/null &
+CLIENT_PID="$!"
+client_sleep_til_boot
+
+echo
+echo "-- Initial state of the client:"
+client_rpc getchainstates
+
+echo
+echo "-- Loading UTXO snapshot into client..."
+client_rpc loadtxoutset "$UTXO_DAT_FILE"
+
+watch -n 0.3 "( tail -n 14 $CLIENT_DATADIR/debug.log ; echo ; ./src/bitcoin-cli -rpcport=$CLIENT_RPC_PORT -datadir=$CLIENT_DATADIR getchainstates) | cat"
+
+echo
+echo "-- Okay, now I'm going to restart the client to make sure that the snapshot chain reloads "
+echo "   as the main chain properly..."
+echo
+echo "   Press CTRL+C after you're satisfied to exit the demo"
+echo
+read -p "Press [enter] to continue"
+
+while kill -0 "$CLIENT_PID"; do
+    sleep 1
+done
+./src/bitcoind $CLIENT_PORTS $ALL_INDEXES -logthreadnames=1 -datadir="$CLIENT_DATADIR" -connect=0 \
+    -addnode=127.0.0.1:$SERVER_PORT "$EARLY_IBD_FLAGS" >/dev/null &
+CLIENT_PID="$!"
+client_sleep_til_boot
+
+watch -n 0.3 "( tail -n 14 $CLIENT_DATADIR/debug.log ; echo ; ./src/bitcoin-cli -rpcport=$CLIENT_RPC_PORT -datadir=$CLIENT_DATADIR getchainstates) | cat"
+
+echo
+echo "-- Done!"