A few weeks ago Matthew (one of the senior engineers on our team) discovered that a fox had somehow gotten into his backyard chicken coop overnight.
Chaos followed.
The chickens scattered in every direction, and some vanished completely. A few cautiously returned later that day, another one came back the next morning, and then a couple of days later yet another chicken reappeared.
The strange part was that there was very little evidence of what had actually happened. There were feathers around the yard but no bodies, leaving no clear signs of which birds had survived and which had not.
For several days, Matthew existed in a strange state of uncertainty that we jokingly referred to as “Schrödinger’s Chickens”. The flock was simultaneously alive and dead until proven otherwise.
Oddly enough, this happens in telecom networks all the time.
The Most Dangerous State in Telecom: “Probably Fine”
After any significant outage, maintenance event, or failover, operators often enter a similar state of uncertainty. Some systems clearly survived and some clearly failed, but others exist in a kind of operational limbo.
Are all SIP registrations back? Did every subscriber reconnect? Is replication healthy? Did the backup system fully take over? Are alarms silent because everything is healthy, or because the monitoring broke too?
In many cases, engineers simply do not know immediately. Unfortunately, telecom networks are remarkably good at appearing healthy while partially broken.
The Problem With Partial Failures
Complete failures are usually easy to detect. A major outage generates alarms, ticket storms, dashboards turning red, and executives suddenly appearing on bridge calls asking for updates every four minutes.
Partial failures are much harder to spot.
Think of a single failed SBC in a cluster, a stale DNS record, a replication process that is quietly stuck, or a subset of subscribers who are unable to re-register after maintenance. These problems can linger for hours or days because the overall network still appears mostly operational.
In other words, the chickens that came back are visible, but the missing ones are much harder to account for.
“No Alarms” Does Not Mean “Healthy”
One of the recurring operational traps in telecom is assuming that the absence of alarms implies system health, but many failures do not trigger dramatic alarms at all.
Registration issues may only affect customers behind specific NAT environments. Traffic imbalances may gradually overload a subset of systems, and failover mechanisms might technically activate while silently degrading capacity. The network continues functioning, just badly enough to create customer pain without creating obvious operational panic.
This is where experienced operators become incredibly valuable. Senior engineers learn to distrust the phrase “everything looks fine” because sometimes the fox has already gotten into the henhouse.
Why Telecom Recovery Is Messy
One of the interesting things about Matthew’s chickens was that recovery didn’t happen instantly or predictably. The flock returned gradually, and networks behave the exact same way.
After a maintenance window, devices reconnect at different rates. DNS caches expire at different times, SIP endpoints retry registrations on varying timers, and traffic patterns slowly normalize over time.
All of this can create misleading snapshots of your network health. Five minutes after a migration, everything may appear broken. Thirty minutes later, it looks mostly healthy. Two hours later, hidden edge cases start emerging.
Operationally, this is why experienced telecom engineers avoid declaring victory too early.
Designing for Certainty
Good telecom operations are not just about redundancy, they are about visibility. Operators need systems that answer specific questions:
- What percentage of endpoints have actually re-registered?
- Which customers stopped generating traffic?
- Are there silent failures hidden behind “healthy” dashboards?
The goal is reducing uncertainty, because uncertainty is expensive and it tends to linger long after the fox leaves.
Eventually, most of Matthew’s chickens came back. But for several days, he lived in a strange operational gray area where he simply didn’t know what state the system was truly in. The most dangerous telecom failures are not always the loudest ones. Sometimes the real risk is not knowing which systems survived, which failed, and which are only pretending to be healthy.
Eventually the chickens either return or they don’t. Unfortunately, dead servers rarely wander back into the coop on their own.
If you are struggling with partial failures, or if you simply want better visibility and certainty out of your voice network, drop us a line. We’re getting ready to launch a new product Award Aware that will provide greater visibility into your network, and we’re looking for beta customers now.
