From 46d7ac4748489efbc5cebdceada2b308f46749f2 Mon Sep 17 00:00:00 2001
From: Ariel Richtman <10679234+arichtman@users.noreply.github.com>
Date: Thu, 26 Dec 2024 16:04:55 +1000
Subject: [PATCH] bug: fix erroneous divide by zero network interface error

---
 modules/nixos/monitoring/node-exporter.yml | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/modules/nixos/monitoring/node-exporter.yml b/modules/nixos/monitoring/node-exporter.yml
index 85d8dbb..5ef5418 100644
--- a/modules/nixos/monitoring/node-exporter.yml
+++ b/modules/nixos/monitoring/node-exporter.yml
@@ -268,7 +268,9 @@ groups:
         description: "Host {{ $labels.instance }} interface {{ $labels.device }} has encountered {{ printf \"%.0f\" $value }} receive errors in the last two minutes.\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"
 
     - alert: HostNetworkTransmitErrors
-      expr: '(rate(node_network_transmit_errs_total[2m]) / rate(node_network_transmit_packets_total[2m]) > 0.01) * on(instance) group_left (nodename) node_uname_info{nodename=~".+"}'
+      expr: '((rate(node_network_transmit_errs_total[2m]) / rate(node_network_transmit_packets_total[2m]) or vector(0)) > 0.01) * on(instance) group_left (nodename) node_uname_info{nodename=~".+"}'
+      # expr: '(rate(node_network_transmit_errs_total[2m]) / rate(node_network_transmit_packets_total[2m]) > 0.01) * on(instance) group_left (nodename) node_uname_info{nodename=~".+"}'
+      # expr: '(rate(node_network_transmit_errs_total{device!~"^wg\d+"}[2m]) / rate(node_network_transmit_packets_total{device!~"^wg\d+"}[2m]) > 0.01) * on(instance) group_left (nodename) node_uname_info{nodename=~".+"}'
       for: 2m
       labels:
         severity: warning