Key takeaways:
- 3CX only shows connected phones — offline devices are invisible in the admin console
- Finding an offline phone means opening every extension one by one and checking the Phones tab
- Controvo’s Phones table shows all phones (online and offline) in one sortable list
- Last Seen Online tracks when each phone last connected, and Last Known IP tracks where
- Sort by Last Seen Online to spot devices that dropped off days or weeks ago
The Problem: 3CX Hides Offline Phones
3CX shows connected phones. Disconnected phones disappear from the interface entirely.
That works until a user reports a dead desk phone. You open their extension in 3CX, click the Phones tab, and check the dropdown. The phone isn’t listed. Now you know it’s offline, but not when it disconnected or where it was connecting from.
Site audits are worse. To find every offline phone across a system, you have to:
- Open each extension individually.
- Click the Phones tab.
- Check the dropdown for registered devices.
- Repeat for every extension.
A 50-extension system means 50 manual lookups. A 200-extension client means it doesn’t get done. You either spend an afternoon clicking through the UI or accept that you don’t know which phones are offline.
What Last Seen Online Tracks
Controvo records two data points for every phone:
- Last Seen Online — when we last observed the phone connected to 3CX.
- Last Known IP — the IP address the phone was using at that time.
Both persist after the phone disconnects. When a device drops off, you keep the context that 3CX throws away.
One Table, Every Phone
The Phones table in Controvo lists all phones regardless of connection status. Online, offline — same list, sortable columns.
Sort by Last Seen Online to find phones that haven’t checked in recently. The oldest timestamps rise to the top. No extension-by-extension searching.
The Last Known IP column narrows down where an offline phone was. That’s often enough to identify a specific site or subnet, especially when you’re managing multiple 3CX systems across locations.
Catch Problems Before Users Report Them
Offline phones stay invisible in 3CX until someone tries to make a call and can’t. That might be days or weeks after the phone disconnected. By then you’ve lost context — was it a firmware update, a network change, or someone unplugging it?
Check the Phones table weekly. A phone missing for 3 days is worth investigating before the user notices. For MSPs managing dozens of systems, this replaces manual phone audits with a single sorted table.
Pair this with custom monitoring thresholds and alerts to cover system health alongside phone tracking, or use Live Data Mode when you need faster refresh intervals during troubleshooting.
Try It
Last Seen Online is available now in the Phones table. Already in the pilot? Log in and check it out. Not yet? Apply for the pilot to get early access.