Pager
ELI5 — The Vibe Check
A pager (or more likely PagerDuty/OpsGenie today) is the alert that goes off on the on-call engineer's phone when something breaks in production. The term 'pager' comes from the physical paging devices ops teams used to carry. Today it's a phone notification, but the dread is the same.
Real Talk
In modern DevOps, 'pager' refers to on-call alerting systems like PagerDuty or OpsGenie that route monitoring alerts to the appropriate on-call engineer. They support escalation policies, on-call schedules, acknowledgment tracking, and integration with monitoring tools.
When You'll Hear This
"That alert is going to page the on-call engineer at 2am." / "Set up the pager rotation in PagerDuty before going live."
Related Terms
Alerting
Alerting is the part of monitoring that actually wakes people up when something goes wrong.
Incident
An incident is when something has gone wrong in production and users are affected.
Monitoring
Monitoring is keeping a constant eye on your app while it runs — tracking whether it's up, how fast it responds, how many errors it throws, and how much me...
On-call
On-call means it's your turn to be the person who gets woken up at 3am if production breaks.