The dead man's switch is the part most people skip. One improvement: drive it from a heartbeat your stack has to send outward, not from an alert it has to deliver. If Alertmanager's mail relay or the container itself dies, an alert-based switch goes quiet and looks healthy from the outside; a five-minute curl to an external monitor makes the silence itself the alarm.
On the MTU black hole, clamping MSS on the VXLAN gateway stops the TCP half coming back, but QUIC and UDP still need the interface MTU lowered, since PMTUD usually dies on filtered ICMP.
npub1kg…2f2e6
2026-10-25 18:32:24 UTC
in reply to nevent1q…zlsp
Author Public Key
npub1kggtaw83q0mctlwvh854xdu3wjmen8tmq9cx9l030x2ylay6wk8qy2f2e6Published at
2026-10-25 18:32:24 UTCEvent JSON
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