SNMP
SNMP brings the infrastructure layer into the same namespace as the process layer: switches, UPS units, PDUs, environmental monitors, printers, industrial routers. Anything with an agent.
Configuration
| Field | Description |
|---|---|
| Name | Connection identifier. |
| Host | Agent IP or hostname. |
| Port | 161 by default. |
| Version | 1, 2c, or 3. |
| Timeout (ms) | Per-request timeout. |
| Retries | Retries before the request fails. |
| Max repetitions | GETBULK window for v2c/v3 walks. Higher is faster but produces larger responses. |
| Probe OID | The OID the connection test reads. 1.3.6.1.2.1.1.1.0 (sysDescr) is a safe universal choice. |
v1 / v2c
| Field | Notes |
|---|---|
| Community | The read community string. |
| Write community | Optional, for SET operations. |
Community strings are transmitted in clear text. On any network you do not fully control, use v3.
v3 (USM)
| Field | Values |
|---|---|
| Security level | noAuthNoPriv, authNoPriv, authPriv |
| Security name | The USM user name |
| Auth protocol | MD5, SHA, SHA-224/256/384/512 |
| Auth key | The authentication passphrase |
| Priv protocol | DES, AES, AES-192/256 |
| Priv key | The privacy passphrase |
| Context name | Optional SNMPv3 context |
Keys are stored encrypted and never returned to the browser; the edit form shows only
has_auth_key / has_priv_key presence flags.
Binding tags
| Field | Notes |
|---|---|
| Address | The OID, numeric (1.3.6.1.2.1.1.3.0) or symbolic if a MIB defines it. |
| Polling mode | poll — SNMP has no subscription. Traps arrive separately. |
| Sampling rate | Poll period. Infrastructure rarely needs faster than 30–60 s. |
Remember the trailing .0 for scalar objects. 1.3.6.1.2.1.1.3 is the object; 1.3.6.1.2.1.1.3.0
is its single instance. Table columns are indexed instead — 1.3.6.1.2.1.2.2.1.10.3 is ifInOctets
for interface 3.
Walking an agent
Walk in the connection's editor (needs View connections) walks the agent's tree and returns each OID with its value and, where a MIB is loaded, its symbolic name. This is how you find out what a device actually exposes, rather than trusting a datasheet.
Vendor MIBs
Standard MIB-II is understood out of the box. Vendor MIBs turn 1.3.6.1.4.1.318.1.1.1.2.2.1.0 into
upsAdvBatteryCapacity.
| Action | Permission |
|---|---|
| List loaded MIBs | View connections |
| Upload a MIB | Create connections |
Uploaded MIBs are compiled by an isolated child process, so a malformed vendor MIB — and they are frequently malformed — cannot crash the gateway. A MIB that fails to compile is rejected with its error; names simply fall back to numeric OIDs.
Traps
Devices push asynchronous notifications (a UPS switching to battery, a link going down). QUBIQ can listen on UDP 162; the listener is opt-in and off by default.
Received traps are resolved against the loaded MIBs — so you see linkDown, not
1.3.6.1.6.3.1.1.5.3 — and kept in a rolling buffer for the operator feed.
The trap feed is in the connection's editor (needs View connections).
SNMP traps are unacknowledged UDP. A trap sent while QUBIQ is restarting is gone. Never rely on traps alone for a condition that matters — poll the underlying value and accept the trap for low latency.
Typical monitoring set
| What | OID | Why |
|---|---|---|
| Uptime | 1.3.6.1.2.1.1.3.0 | A reset counter means the device rebooted |
| Interface operational status | 1.3.6.1.2.1.2.2.1.8.<if> | Link up/down — a good on_boolean alarm |
| Interface in/out octets | 1.3.6.1.2.1.2.2.1.10/16.<if> | Throughput; counters, so trend the rate |
| Interface errors | 1.3.6.1.2.1.2.2.1.14/20.<if> | Rising errors precede a failing link |
| UPS battery capacity, on-battery status | vendor MIB | Facility power |
| Temperature | vendor MIB | Cabinet/environment |
Counters wrap. Alarm on the rate of change, not the raw counter, using a pipeline or a derived tag.
Troubleshooting
| Symptom | Check |
|---|---|
| Timeout on every request | Agent not enabled, firewall on UDP 161, or an ACL restricting source addresses. |
Works with snmpwalk, not QUBIQ | Source-IP ACL on the agent — add the QUBIQ host. |
| v3 authentication fails | Security level must match the agent exactly; authPriv with only an auth key configured will fail. |
| Some OIDs return nothing | Missing .0 on a scalar, or the object is not implemented by that device. |
| Names show as numeric OIDs | The vendor MIB is not uploaded, or failed to compile. |
| Walk is very slow | Reduce max repetitions, or walk a subtree instead of the whole agent. |
Next
→ TCP/UDP