diff --git a/pageserver/src/bin/pageserver.rs b/pageserver/src/bin/pageserver.rs
index 457dc6d09e05..e9433de05b93 100644
--- a/pageserver/src/bin/pageserver.rs
+++ b/pageserver/src/bin/pageserver.rs
@@ -155,6 +155,9 @@ fn initialize_config(
 
     let file_contents: Option<toml_edit::Document> = match std::fs::File::open(cfg_file_path) {
         Ok(mut f) => {
+            if init {
+                anyhow::bail!("config file already exists: {cfg_file_path}");
+            }
             let md = f.metadata().context("stat config file")?;
             if md.is_file() {
                 let mut s = String::new();
diff --git a/test_runner/regress/test_pageserver_api.py b/test_runner/regress/test_pageserver_api.py
index 55165e3c860d..be351db429c5 100644
--- a/test_runner/regress/test_pageserver_api.py
+++ b/test_runner/regress/test_pageserver_api.py
@@ -12,7 +12,6 @@
 from fixtures.utils import wait_until
 
 
-# test that we cannot override node id after init
 def test_pageserver_init_node_id(
     neon_simple_env: NeonEnv, neon_binpath: Path, pg_distrib_dir: Path
 ):
@@ -49,7 +48,7 @@ def run_pageserver(args):
 
     bad_reinit = run_pageserver(good_init_cmd)
     assert bad_reinit.returncode == 1, "pageserver refuses to init if already exists"
-    assert "already exists, cannot init it" in bad_reinit.stderr
+    assert "config file already exists" in bad_reinit.stderr
 
 
 def check_client(env: NeonEnv, client: PageserverHttpClient):