Reference

Quick-reference tables for Predict:

• the available change types;
• the platforms and protocols Forward Predict re-models;
• the best-path order it applies;
• the outputs a prediction produces.

See How Predict Works for the workflow and the behavior behind these tables.

Wizard Steps

The Forward Predict wizard has five steps:

Step	Heading in the product	Action
Select the base	Select the base Snapshot for analysis	Pick the collected snapshot to model against.
Define intent	Define intent of the change	Optional: attach the intent checks to re-run.
Modify devices	Modify devices	Enter per-device CLI, config, or firewall changes.
Review all changes	Review all changes	Review every change in the set, grouped by device.
Run predict analysis	Run predict analysis	Commit the set, produce the predicted snapshot, read the report.

Change Types

Change type	Scope	Notes
CLI commands	Any device on a supported platform.	Vendor-native config lines merged into the running config.
Config file replacement	Any parseable device.	Replaces the device's running config directly.
Firewall rule change	Palo Alto (PAN-OS) local rules only.	Add, edit, delete, or reorder a security rule.
BGP advertisement inject	Model level; any BGP scenario.	Model an external peer advertising a prefix. See supported address families.
BGP advertisement withdraw	Model level; any BGP scenario.	Model a route being withdrawn.

Forward Predict does not model these as change types:

• Topology changes: adding or removing a device or link, or a link going down.
• VLAN, STP, and interface-state changes.

See Prediction Scope → Changes Predict Does Not Model.

Command Merge by Vendor

A CLI change merges into the device's current config with vendor-aware logic (command order and no-form or set/delete overrides), not a text append. Eight OS families support command merge:

Vendor	OS families	Merge semantics
Cisco	IOS-XE, IOS, NX-OS, IOS-XR, ASA	Ordered CLI with no-form overrides.
Arista	EOS	Ordered CLI with no-form overrides.
Juniper	Junos, SRX	Structured set and delete against config.

A device on any other platform accepts a Config file change (full running-config replacement) but not a merged CLI change. If the previewed config from a CLI change does not match what the commands should produce, switch to Config file. See Troubleshooting → The previewed config isn't what my commands should produce.

Routing Protocols

Protocol	Re-propagated	Notes
BGP (IPv4 / IPv6 unicast)	Yes	Default routing protocol.
Cross-protocol redistribution	Into BGP	Routes redistributed into BGP re-propagate in the BGP domain.
OSPF	No	Not in 26.9; planned for a later release.
Static and connected routes	No	Not in 26.9; planned for a later release.
SD-WAN overlay (OMP)	No	Not in 26.9; planned for a later release.
IS-IS	No	Not re-propagated; planned to follow.
EIGRP	No	Not re-propagated; planned to follow.
RIP	No	Not re-propagated; planned to follow.

Forward Predict can read an IS-IS, EIGRP, or RIP route that a propagated protocol redistributes, but it does not re-compute those protocols themselves. For example, an EIGRP route already redistributed into BGP re-propagates as a BGP route, but editing the EIGRP configuration that would add or drop that route has no effect, because it does not recompute EIGRP. See Prediction Scope → Supported Routing Protocols.

Routing-State Synthesis Platforms

A routing change produces a fully re-synthesized routing table only on these platforms:

Vendor	Platforms
Cisco	IOS, IOS-XE, IOS-XR, NX-OS, NX-OS (ACI), ASA
Juniper	Junos, SRX
Arista	EOS
Fortinet	FortiOS
Palo Alto	PAN-OS

MPLS forwarding-state synthesis covers a subset: Cisco IOS-XE, IOS-XR, and NX-OS.

On any other platform, Forward Predict includes the device in the model but does not re-synthesize its routing table. A base-vs-predicted routing-table diff then shows no change on that device, even where the change would alter its routes. See Troubleshooting → A route-table diff shows no change on some devices.

BGP Best-Path Order

When several BGP routes compete, Forward Predict selects the best path in this order:

1. Highest weight
2. Highest local-preference
3. Locally originated
4. Shortest AS-path
5. Lowest origin type
6. Lowest MED
7. eBGP over iBGP
8. Lowest IGP metric to the next hop
9. Peer tiebreakers

Forward Predict installs all equal-cost paths, up to the device's configured maximum-paths limit.

OSPF Route Preference

OSPF is not available in 26.9

OSPF prediction is not available in 26.9. This order takes effect when OSPF prediction ships in a later release. See Supported Routing Protocols.

Forward Predict selects an OSPF route by type first, then by cost:

1. Route type, most preferred first: intra-area, inter-area, external Type 1 (E1), external Type 2 (E2). Type preference is absolute; a lower cost never overrides it.
2. Lowest cost, within the same OSPF route type.

Prefix-Search Outcomes

Prefix search and trace label each device's outcome for a prefix:

Outcome	Meaning
Installed	The route won best-path selection and is installed on the device.
Filtered out	An import or export policy dropped the route before best-path selection.
Not preferred	The device received the route but a competing route won best-path selection.

See Prefix Search & Trace.

Analysis Outputs

A committed prediction produces these outputs, all scoped to the change set:

Output	What it shows
Config diff	Base vs predicted running config, per device.
Route trace	Per-prefix BGP propagation with per-hop policy and attributes.
Intent checks	Path Analysis, Verify, and NQE re-run on the predicted snapshot.
Exported report	A PDF of the report (browser print) and a config-changes .zip archive.

Forward Predict exports the report only as a PDF and a config-changes .zip.

Device Editor

In the device editor, the Modify using: radio selects how to describe a change:

Radio label	Effect
CLI commands	Enter vendor-native config lines merged into the running config.
Config file	Paste a full running config that replaces the device's baseline.