chore: regenerate addrbook.json for in-place-testnet (#21941)

CHANGELOG.md

@@ -139,6 +139,7 @@ Every module contains its own CHANGELOG.md. Please refer to the module you are i
 * (internal) [#21412](https://github.com/cosmos/cosmos-sdk/pull/21412) Using unsafe.String and unsafe.SliceData.
 * (client) [#21436](https://github.com/cosmos/cosmos-sdk/pull/21436) Use `address.Codec` from client.Context in `tx.Sign`.
 * (x/genutil) [#21249](https://github.com/cosmos/cosmos-sdk/pull/21249) Incremental JSON parsing for AppGenesis where possible.
+* (testnet) [#21941](https://github.com/cosmos/cosmos-sdk/pull/21941) Regenerate addrbook.json for in place testnet.
 
 ### Bug Fixes
 

server/start.go

@@ -9,6 +9,7 @@ import (
 	"io"
 	"net"
 	"os"
+	"path/filepath"
 	"runtime/pprof"
 	"strings"
 	"time"
@@ -780,6 +781,17 @@ func testnetify[T types.Application](ctx *Context, testnetAppCreator types.AppCr
 		return nil, err
 	}
 
+	// Regenerate addrbook.json to prevent peers on old network from causing error logs.
+	addrBookPath := filepath.Join(config.RootDir, "config", "addrbook.json")
+	if err := os.Remove(addrBookPath); err != nil && !os.IsNotExist(err) {
+		return nil, fmt.Errorf("failed to remove existing addrbook.json: %w", err)
+	}
+
+	emptyAddrBook := []byte("{}")
+	if err := os.WriteFile(addrBookPath, emptyAddrBook, 0o600); err != nil {
+		return nil, fmt.Errorf("failed to create empty addrbook.json: %w", err)
+	}
+
 	// Load the comet genesis doc provider.
 	genDocProvider := node.DefaultGenesisDocProviderFunc(config)