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Device discovery & troubleshooting
The collector finds printers by scanning the subnet of every network interface on its host and asking each address, over SNMP, "are you a printer?" Anything that answers with a printer MIB is added to the site and polled from then on. This page covers what to do when the list isn't what you expected.
How discovery works
- On start, and periodically after that, the collector enumerates its host's IPv4 interfaces and scans each
/24(you'll seediscovery: scanning [192.168.10.0/24]in the log). - Every address gets an SNMP v2c query with the
publiccommunity. Devices that identify as printers are kept; everything else is ignored. - Found devices are polled on the site's schedule (default hourly) for meters, supply levels, and status. Readings and their timestamps are kept as history.
- Rescans continue in the background, so a printer added next month is picked up without anyone touching the collector.
A device is missing
Work down this list; the first three account for almost every case.
| Cause | How to check | Fix |
|---|---|---|
| SNMP is disabled on the printer | Open the printer's web page → Network / Security settings. Many newer Canon, HP, and Xerox models ship with SNMP v1/v2 off. | Enable SNMP v1/v2c read access with community public. Read-only is all MeterBeam needs. |
| Non-default community string | Same screen — the read community is something other than public. | Either set it back to public for read-only, or contact us and we'll set a per-site community. |
| Different VLAN / subnet | Printer IP isn't in any range the log shows under discovery: scanning. | Install the collector on a host that has an interface on the printer VLAN, or ask the customer's IT to allow UDP 161 from the collector host to the printer subnet. Devices reachable by route are polled once known; contact us to add a static range for the site. |
| Host firewall blocks SNMP | Windows Defender Firewall or a third-party endpoint product blocking outbound UDP 161 from MeterBeamAgent.exe. | Allow outbound UDP 161 for the service, or the program path C:\Program Files\MeterBeam\MeterBeamAgent.exe. |
| USB-only or Wi-Fi Direct printer | Device has no LAN IP. | Not discoverable by any DCA. Put it on the network if you need it monitored. |
| Printer was asleep during the scan | Some devices don't answer SNMP in deep sleep. | It'll be picked up on a later rescan. Printing a test page wakes the device immediately. |
A device shows up but with no meters or toner
The printer answered basic identity but not the standard printer MIB counters. This is common on very old devices, label printers, and a few consumer models. MeterBeam maintains per-model profiles for vendor-specific counters; if a business-class copier or MFP is showing dashes where meters should be, email the make, model, and firmware version to support@meterbeam.com and we'll add a profile. Consumer inkjets and label printers are generally not worth chasing.
A device is marked offline
OFFLINE means the device was discovered and polled successfully before, but hasn't answered for longer than the offline threshold (default 24 hours, adjustable per site in Site → Offline alert hrs). Usual reasons, in order: the printer is powered off or unplugged from the network; it got a new IP from DHCP (the collector will re-find it on the next scan and reconcile by serial number); or it was moved to another site. If it's genuinely gone, retire it (below) so it stops generating alerts and stops counting toward your device total.
The whole site is "collector down"
COLLECTOR DOWN means the site's collector hasn't checked in. Every device at that site is unobservable until it returns, so this outranks any single-device problem in the attention queue. Check, in order:
- Is the host powered on and connected? (Laptop lids and "shut down at 6 pm" policies are the classic causes.)
- Is the service running? Windows:
services.msc→ MeterBeamAgent should be Running. Linux:systemctl status meterbeam-agent. - Can the host reach the internet? Open
https://app.meterbeam.comin a browser on that machine. If the customer added a web proxy or a new firewall rule, this is where it shows. - Read the log tail. A repeated connection error names the problem; a clean "poll: n/n devices answered" with no check-in means the outbound path is blocked.
If the host is gone for good, install the collector on a new machine and revoke the old row — see Moving a collector.
Hiding, retiring, and unmonitoring
- Unmonitored — discovered but you don't care about it (a receipt printer, a personal desk inkjet). It stays known, stops polling, and is hidden from tables unless you tick show unmonitored. It does not count as a device for billing.
- Retired — the device is permanently gone. History is kept for reporting, it's hidden unless you tick show retired, and it never counts toward device totals or alerts.
Both are set from the device's detail view. Prefer retiring over deleting — old readings are what make your volume reports and burn rates accurate.