diff --git a/pkg/proxy/autodiscover.go b/pkg/proxy/autodiscover.go
index ba1f45fc..37306bd5 100644
--- a/pkg/proxy/autodiscover.go
+++ b/pkg/proxy/autodiscover.go
@@ -107,6 +107,17 @@ func (s *server) reconcileClickHouseAutodiscover(ctx context.Context, entry Clic
 		return
 	}
 
+	// A failed probe means we could not determine availability, not that the
+	// datasource is gone. Leave the current state untouched so a transient
+	// error (timeout, network blip, 5xx) does not tear down a healthy
+	// datasource. Removal only happens when a probe succeeds and reports the
+	// database absent.
+	if err != nil {
+		logger.WithError(err).Debug("ClickHouse autodiscovery probe failed; leaving current state unchanged")
+
+		return
+	}
+
 	if available && !*present {
 		if !s.addAutodiscoveredClickHouseCluster(target.cluster) {
 			return
@@ -126,12 +137,6 @@ func (s *server) reconcileClickHouseAutodiscover(ctx context.Context, entry Clic
 		return
 	}
 
-	if err != nil {
-		logger.WithError(err).Debug("ClickHouse autodiscovery probe failed")
-
-		return
-	}
-
 	logger.WithField("available", available).Debug("ClickHouse autodiscovery state unchanged")
 }
 
diff --git a/pkg/proxy/server_test.go b/pkg/proxy/server_test.go
index d5071355..7d1390b6 100644
--- a/pkg/proxy/server_test.go
+++ b/pkg/proxy/server_test.go
@@ -744,8 +744,17 @@ func TestAutodiscoverReconcilesClickHouseDatasource(t *testing.T) {
 		t.Fatalf("/datasources ClickHouseInfo[0].Description = %q, want custom description", datasources.ClickHouseInfo[0].Description)
 	}
 
+	// A transient probe error must not remove a healthy datasource.
 	pingOK = false
 	srv.reconcileClickHouseAutodiscover(t.Context(), entry, &present)
+	if !present || !srv.clickhouseHandler.HasCluster("local-kurtosis") {
+		t.Fatal("expected datasource to survive a transient probe error")
+	}
+	pingOK = true
+
+	// A successful probe that reports the database absent removes it.
+	databaseExists = false
+	srv.reconcileClickHouseAutodiscover(t.Context(), entry, &present)
 	if present {
 		t.Fatal("expected datasource to become absent")
 	}
@@ -756,7 +765,7 @@ func TestAutodiscoverReconcilesClickHouseDatasource(t *testing.T) {
 		t.Fatalf("ClickHouseDatasourceInfo() after removal = %v, want empty", got)
 	}
 
-	pingOK = true
+	databaseExists = true
 	srv.reconcileClickHouseAutodiscover(t.Context(), entry, &present)
 	if !present {
 		t.Fatal("expected datasource to become present again")