From 961cdfbcd266c6eccbcbcb195954f6b72706b0ae Mon Sep 17 00:00:00 2001
From: Till JS <tills95@gmail.com>
Date: Mon, 30 Mar 2026 19:35:28 +0200
Subject: [PATCH] fix(promtail): add default tier label to prevent empty label
 stream errors

Containers that don't match any tier regex had no labels, causing Loki to
reject the stream with "at least one label pair is required".

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---
 docker/promtail/config.yaml | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/docker/promtail/config.yaml b/docker/promtail/config.yaml
index 3b55a41eb..8f0380399 100644
--- a/docker/promtail/config.yaml
+++ b/docker/promtail/config.yaml
@@ -76,6 +76,12 @@ scrape_configs:
         target_label: "tier"
         replacement: "service"
 
+      # Default tier for anything unmatched
+      - source_labels: ["tier"]
+        regex: "^$"
+        target_label: "tier"
+        replacement: "other"
+
       # Drop monitoring container logs to save space (they're noisy)
       - source_labels: ["tier"]
         regex: "monitoring"