A CCTV camera can be perfectly healthy and still disappear after a router change.

That is one of the more frustrating faults we see on inherited and expanding systems. The cameras worked before. The recorder worked before. Then a fibre provider, IT company or well-meaning technician replaces a router and suddenly the cameras are offline, remote viewing is broken or the NVR cannot find devices that were working the previous week.

The fault is not always the new router.

The fault is usually that nobody protected the IP structure that the CCTV system relied on.

CCTV is not just plugged into the internet

An IP camera system depends on addresses.

Every camera, recorder, switch, access point, router and remote-access rule needs to know where the other equipment lives. If the old camera network used one range and the new router uses another, the system may not automatically follow.

For example, the old installation may have cameras sitting on one fixed range, while the new router starts handing out a different range through DHCP. The recorder may still be looking for cameras on the old addresses. Remote access may still point to the old gateway. Reservations may disappear. Port rules may be lost. Passwords may still be correct, but the network path is gone.

From the client’s side, the story becomes simple: “The cameras are down.”

From the technical side, the address plan has been broken.

Why matching the old range can save hours

When a system has been running for years, there is often value in preserving the old IP range if it is technically sensible.

That does not mean copying a bad network forever. Sometimes a messy network should be cleaned up. But if a site has many fixed cameras, a recorder, remote users and possibly linked buildings, changing the range without planning can create unnecessary downtime.

On support work, one of the first questions is often: what was the old LAN range?

If the new router can be configured to match the previous range, many fixed devices may return without touching every camera. If the range must change, then each camera, recorder setting, gateway, remote-access rule and documentation sheet should be updated deliberately.

The expensive mistake is changing the router first and discovering the CCTV dependency afterwards.

DHCP is useful, but not for everything

DHCP is the system that automatically gives addresses to devices. It is useful for laptops, tablets and general network clients.

Critical CCTV devices should not depend on random addressing.

The recorder should have a known address. Cameras should have fixed addresses or proper reservations. Network equipment should be labelled and documented. The DHCP scope should not conflict with manually assigned camera addresses.

If a router is replaced and all DHCP reservations disappear, a system that was previously stable can become unpredictable. A camera may receive a different address. Another device may take an address the recorder expects. Remote viewing may still be looking in the wrong place.

That is why router management belongs inside the CCTV support conversation.

Multi-building sites make this more important

The problem becomes more serious when CCTV spans more than one building, yard, warehouse, gatehouse or linked site.

Now the network may include point-to-point links, fibre runs, multiple switches, secondary cabinets, LTE backup, office networks and separate equipment rooms. If two routers use the same range, or if a second site is joined without checking existing camera addresses, devices can clash.

The symptoms can be strange:

  • some cameras work locally but not remotely,
  • one building drops after a power cycle,
  • the NVR finds cameras and then loses them,
  • remote access works from one network but not another,
  • cameras appear online only when connected directly.

Those are not always camera faults. They are often addressing and routing faults.

What should be documented

A professional CCTV handover should record the basics:

  • router LAN range,
  • recorder IP address,
  • camera IP address range,
  • switch and cabinet locations,
  • DHCP scope,
  • reservations where used,
  • remote-access method,
  • relevant port or VPN details,
  • administrator ownership,
  • any linked building or secondary router arrangement.

This is not paperwork for paperwork’s sake. It is what allows a system to survive normal changes: fibre upgrades, router replacements, network expansion, power failures and future support.

DG Technologies’ approach

DG Technologies treats the router as part of the CCTV system when cameras depend on IP communication.

That does not mean the AV or CCTV installer must replace the client’s IT provider. It means the network responsibilities must be clear. If a multi-million rand property or business relies on cameras, automation, access control and remote support, the IP structure cannot be left to chance.

Before a router changes, ask what else depends on it.

In many CCTV faults, the camera was never the problem. The address plan was.