WDM Nodes¶

A WDM node is the per-device instance of a WDM profile. It is a one-to-one overlay on dcim.Device and owns the actual WdmChannel and WdmLinePort rows for that device.

Lifecycle¶

Nodes are normally created automatically. When a dcim.Device is saved and its DeviceType has a WDM profile, a post_save signal handler schedules a WdmNode to be created on transaction commit, copying node_type and grid from the profile.

You can also create a WdmNode manually from WDM > Nodes > Add, selecting the device. This is useful when a device was imported before its DeviceType got a profile.

When a WdmNode is created, _auto_populate_channels() runs:

The profile's WdmChannelPlan rows are loaded.
For each plan, the plugin looks up FrontPort instances on the new device by name (matching the plan's mux_front_port_template.name and demux_front_port_template.name).
One WdmChannel is bulk-created per plan, with foreign keys to the matching front ports.

If a front port template name does not match an existing FrontPort on the device (for example because port templates were renamed after device creation), the channel is still created with a null front port. You can fix this later via Port Sync.

Amplifier nodes (node_type=amplifier) skip channel auto-population because amplifiers do not carry per-channel client ports.

Fields¶

Field	Notes
`device`	One-to-one to `dcim.Device`
`node_type`	`terminal_mux`, `oadm`, `roadm`, `amplifier`
`grid`	Same choices as `WdmProfile.grid`
`description`	Free text
`expected_port_hash`	Internal: SHA-256 of the expected PortMapping state
`port_sync_valid`	Internal: True when actual PortMappings match expected hash

The two internal fields are explained in Port Sync.

Fixed vs. ROADM nodes¶

The model distinguishes between fixed and ROADM nodes via the is_fixed property:

is_fixed = True for terminal_mux, oadm, and amplifier. The channel-to-port assignments and line port configuration are hardware determined; modifying them is rejected at save() time.
is_fixed = False for roadm. Channel assignments can be remapped at runtime, and the Wavelength Editor is exposed as a tab on the node detail page.

For fixed nodes, only WdmChannel.status (Available / Reserved / Active) can be changed after creation.

Detail page¶

The WDM Node detail page shows:

A header with port-sync status. When out of sync, a banner lets operators trigger Sync Now.
A stacked status bar across all channels showing active / reserved / available split, broken into connected and disconnected buckets (a channel is "connected" when at least one of its MUX or DEMUX front ports has a cable).
A Channels tab listing every WdmChannel on the node.
A Line Ports tab listing every WdmLinePort (the trunk RearPort designations).
A Wavelength Editor tab (ROADM nodes only) for live channel reassignment.

Line ports¶

WdmLinePort records identify which of the device's RearPort instances carry trunk wavelengths and which direction they belong to. The plugin does not create them automatically -- once a Device exists, you must add one line port per trunk RearPort before the wavelength-path trace will recognise that side of the device as a trunk.

Field	Notes
`wdm_node`	Parent node
`rear_port`	FK to `dcim.RearPort` (must belong to the same device)
`direction`	`common`, `east`, or `west`
`role`	`tx`, `rx`, or `bidi`

The recipe per hardware class:

Hardware	Rear port	direction	role
Duplex MUX	`COM-TX`	`common`	`tx`
Duplex MUX	`COM-RX`	`common`	`rx`
Single-fibre MUX	`COM`	`common`	`bidi`
2-degree ROADM	`LINE-EAST-TX`	`east`	`tx`
2-degree ROADM	`LINE-EAST-RX`	`east`	`rx`
2-degree ROADM	`LINE-WEST-TX`	`west`	`tx`
2-degree ROADM	`LINE-WEST-RX`	`west`	`rx`
EDFA	`LINE-OUT`	`common`	`bidi`

Add them from WDM > Line Ports > Add or via bulk CSV import. The fields are deterministic per DeviceType, so a single CSV per hardware model can provision every device of that model.

Constraints prevent two line ports on the same node from sharing a rear port, and from having the same direction-role pair.

Patch panels do not need line ports; they appear in the trace via their ordinary cable terminations.

Bulk operations¶

The list view provides bulk import and bulk delete. Bulk import accepts a CSV or YAML payload with device, node_type, grid, and description columns.