VDSL2-LINE-MIB

MIB Reference — IPNetwork Monitor · Updated September 09, 2026

All MIBsVDSL2-LINE-MIB

Organization: ADSLMIB Working Group

Last Updated: 2009-09-30

Category: DSL and Broadband, Network Interfaces

Description: Manages VDSL2 line interfaces per ITU-T G.993.2, also applicable to ADSL, ADSL2, and ADSL2+ interfaces for unified xDSL management (RFC 5650).

IPNetwork Monitor uses several OIDs from this MIB in network discovery and polling the applicable devices. Start monitoring VDSL2-LINE-MIB with a free 30-day trial of IPNetwork Monitor.

What Is VDSL2-LINE-MIB?

VDSL2-LINE-MIB, published as RFC 5650, is a vendor-neutral IETF standards-track MIB for managing VDSL2 lines per ITU-T G.993.2, and is also applicable to ADSL, ADSL2, and ADSL2+ interfaces, unifying xDSL line management under one module. It exposes line configuration data (profile/template settings), operational status, and command/control objects that trigger line diagnostics and mode changes. For hardware and software status monitoring it is central to xDSL health: it reports line up/down state, negotiated templates, and diagnostic self-test outcomes (loop diagnostics, bit-swap tests) that reveal line degradation, noise, or transceiver-level faults. It builds on and extends the earlier ADSL-LINE-MIB defined in RFC 2662, superseding parts of it for unified xDSL management across generations. It is deployed on DSL access multiplexers (DSLAMs) and DSL modems/routers at customer premises across broadband access networks, and the VDSL2-LINE-MIB MIB is typically the first module loaded when troubleshooting a DSLAM line profile mismatch or repeated automode fallback.

IPNetwork Monitor allows you to monitor SNMP objects defined in VDSL2-LINE-MIB. Use the built-in SNMP Monitoring Browser to explore available variables, view their current values and descriptions, and select the objects you want to monitor. You can then create SNMP monitors, configure thresholds, and receive alerts when monitored values change.

Supported Devices

  • vendor-neutral, standards-based MIB, not tied to a specific manufacturer
  • DSL access multiplexers (DSLAMs)
  • VDSL2/ADSL modems and routers

Monitoring Examples

An operator polls xdsl2LineTable/xdsl2LineEntry per interface to compare the active configuration against xdsl2LineConfTemplate and xdsl2LineAlarmConfTemplate, spotting a line that has fallen back to a lower-throughput template after repeated xdsl2LineCmndAutomodeColdStart events. Triggering xdsl2LineCmndConfLdsf (loop diagnostics self-test) and reading xdsl2LineCmndConfLdsfFailReason lets an admin diagnose why a subscriber line is not training up correctly. Similarly, xdsl2LineCmndConfBpsc together with its xdsl2LineCmndConfBpscFailReason and xdsl2LineCmndConfBpscRequests objects supports bit-swap testing to catch marginal line conditions before they cause an outage.

What Can Be Monitored

  • line operational status
  • negotiated line profile/template
  • loop diagnostics self-test results
  • bit-swap test results and failure reasons
  • cold-start/automode fallback events
Imported Objects

From HC-PerfHist-TC-MIB

HCPerfIntervalThreshold
HCPerfTimeElapsed

From IF-MIB

ifIndexOBJECT-TYPE

From SNMP-FRAMEWORK-MIB

SnmpAdminString

From SNMPv2-CONF

MODULE-COMPLIANCE
NOTIFICATION-GROUP
OBJECT-GROUP

From SNMPv2-SMI

Counter32
Integer32
MODULE-IDENTITY
NOTIFICATION-TYPE
OBJECT-TYPE
Unsigned32
transmission

From SNMPv2-TC

RowStatus
TruthValue

From VDSL2-LINE-TC-MIB

Xdsl2Band
Xdsl2BandUs
Xdsl2BitsAlloc
Xdsl2BpscResult
Xdsl2CarMask
Xdsl2ChAtmStatus
Xdsl2ChInitPolicy
Xdsl2ChInpReport
Xdsl2ChPtmStatus
Xdsl2ConfPmsForce
Xdsl2Direction
Xdsl2InitResult
Xdsl2LastTransmittedState
Xdsl2LdsfResult
Xdsl2LineBpsc
Xdsl2LineCeFlag
Xdsl2LineClassMask
Xdsl2LineLdsf
Xdsl2LineLimitMask
Xdsl2LinePmMode
Xdsl2LineProfiles
Xdsl2LinePsdMaskSelectUs
Xdsl2LineReset
Xdsl2LineSnrMode
Xdsl2LineStatus
Xdsl2LineTxRefVnDs
Xdsl2LineTxRefVnUs
Xdsl2LineUs0Disable
Xdsl2LineUs0Mask
Xdsl2MaxBer
Xdsl2MrefPsdDs
Xdsl2MrefPsdUs
Xdsl2OperationModes
Xdsl2PowerMngState
Xdsl2PsdMaskDs
Xdsl2PsdMaskUs
Xdsl2RaMode
Xdsl2RfiBands
Xdsl2ScMaskDs
Xdsl2ScMaskUs
Xdsl2SymbolProtection
Xdsl2SymbolProtection8
Xdsl2TransmissionModeType
Xdsl2Tssi
Xdsl2Unit
Xdsl2UpboKLF

How to Use in IPNetwork Monitor

Example using xdsl2LineBandStatusSnrMargin OID:

Select a VDSL2 DSLAM or modem/transceiver as the target host to create a monitor — the SNMP service should be up and running on it. Click New Monitor, then check SNMP Custom on the Favorites tab, click Next, and confirm the host. On the next page, click Select... to open the built-in SNMP MIB Browser and type xdsl2LineBandStatusSnrMargin into the Find box to locate it in the OID tree, selecting the specific row/instance you want to monitor since this is a table column, then select it and click OK. It reports the SNR margin for this VDSL2 band, in units of 0.1 dB — the maximum increase in received noise power the line could tolerate while still meeting its error-rate target. On the monitor's Main parameters page you can set the target's SNMP port (default 161), credentials, polling interval, and other settings — see the SNMP Monitor help for details. On the State conditions and Alerting tabs, configure when the monitor should change state and trigger an alert; since this is an Integer32-type OID, Value bounds is the most useful condition here — trigger an alert if the value drops below 60 (i.e. 6.0 dB), since low SNR margin often precedes line errors or a lost sync. Click Finish to create the monitor; you can adjust any parameter later.

See also: xdsl2LineStatusActPsdDs

OIDs

FAQ

What is VDSL2-LINE-MIB used for in a broadband access monitoring setup?
It's the RFC 5650 IETF standard MIB for managing VDSL2 lines (also applicable to ADSL/ADSL2/ADSL2+), exposing line configuration/profile settings, operational status, and diagnostic command/control objects. On a DSLAM or customer-premises modem it reports line up/down state, the negotiated template, and diagnostic self-test outcomes like loop diagnostics and bit-swap tests that reveal line degradation, noise, or transceiver-level faults.

When would I load VDSL2-LINE-MIB while troubleshooting a DSL line?
VDSL2-LINE-MIB is typically the first module loaded when troubleshooting a DSLAM line-profile mismatch or repeated automode fallback, since its objects show the negotiated line profile and cold-start/automode fallback events that indicate why a line isn't training to its expected VDSL2 mode.

RFC description

Manages VDSL2 line parameters and performance metrics per RFC 5650.

Start monitoring vendor-neutral, standards-based MIB, DSL access multiplexers (DSLAMs), VDSL2/ADSL modems and routers (line up/down/template/diagnostic status) with a free 30-day trial of IPNetwork Monitor. Import MIBs, browse SNMP OIDs, create custom SNMP monitors, configure alerts, and monitor any SNMP-enabled network device from a single console.

Download VDSL2-LINE-MIB