BGP — alert when a peer session is down
A BGP session with an upstream / cloud peering drops — half of routes are gone. The peer does not notify you, and your network monitoring (if any) often is not wired to BGP state.
Recipe
bash
#!/usr/bin/env bash
# /etc/cron.d/bgp-session
# */1 * * * * root /opt/bgp-session.sh
# Works with FRRouting (vtysh) — adapt for bird/junos as needed
DOWN=$(vtysh -c 'show bgp summary' \
| awk '/^[0-9]/ && $11 != "Established" {print $1}' \
| tr '\n' ',')
if [ -n "$DOWN" ]; then
curl -fsS "$HEARTBEAT_URL" --data-urlencode "bgp_down=$DOWN"
exit 2
fi
echo "OK (all peers Established)"Same thing in Enterno.io
Wire to an Enterno heartbeat — learn the peer dropped immediately, and your alert beats the customer-ticket pile-up.
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