Topolograph

Topolograph is a web-based Python tool designed to visualize OSPF and IS-IS network topologies and analyze them offline — with no logins or passwords required.

Topolograph builds OSPF/IS-IS network topology based on Link-State Database (LSDB) data collected from a single network device (thanks to the distributed nature of OSPF and IS-IS 🙂). You can upload LSDB output as a text file, or establish a GRE or BGP-LS session using OSPF Watcher or IS-IS Watcher. BGP-LS carries link-state from either OSPF or IS-IS into Topolograph, depending on which Watcher you use; visualize the topology in a local, Dockerized Topolograph UI.

Once uploaded, the topology represents a snapshot of your network state. After making changes — for example, redistributing routes from BGP into OSPF using route-maps and prefix-lists — you can upload the updated topology and compare it with the previous one to clearly see what has changed.

Key Features

• No logins or passwords required — accept LSDB data from text files or via REST API
• Docker version available — run a local instance of Topolograph on your PC
• Visualize OSPF and IS-IS network topologies
• Build shortest paths between any nodes
• Discover backup paths, including secondary backup paths
• Simulate link failures and analyze network reaction
• Simulate router failures and observe traffic flow around failed nodes
• Analyze network behavior when IGP link costs change
• Identify the most loaded nodes and links, as well as fault-tolerant elements
• Compare network states across different points in time
• Ingest topology over BGP-LS from OSPF or IS-IS domains (via OSPF Watcher or IS-IS Watcher)
• Detect asymmetric routing paths
• Discover backed-up and non-backed-up networks using the Analytics / Network Heatmap
• Build and visualize arbitrary topologies using YAML-based definitions

Real-Time Monitoring

Topolograph supports real-time monitoring of changes in OSPF and IS-IS domains using Watcher agents:

• OSPF Watcher
• IS-IS Watcher

Supported vendors for OSPF visualization

| Vendor | LSA1 | LSA2 | LSA5 | SDK nornir driver support | | -------------- | ---------------------------------------------- | ----------------------------------------------- | ------------------------------------------------ | ------------------------- | | Cisco | show ip ospf database router | show ip ospf database network | show ip ospf database external | YES | | Cisco NX-OS | show ip ospf database router detail | show ip ospf database network detail | show ip ospf database external detail | YES | | Quagga | show ip ospf database router | show ip ospf database network | show ip ospf database external | YES | | Ruckus | show ip ospf database link-state router | show ip ospf database link-state network | show ip ospf database external-link-state | YES | | Juniper | show ospf database router extensive | no-more | show ospf database network extensive | no-more | show ospf database external extensive | no-more | YES | | Bird | show ospf state all | show ospf state all | show ospf state all | YES | | Nokia | show router ospf database type router detail | show router ospf database type network detail | show router ospf database type external detail | YES | | Mikrotik | /routing ospf lsa print detail file=lsa.txt | /routing ospf lsa print detail file=lsa.txt | /routing ospf lsa print detail file=lsa.txt | YES | | Huawei | display ospf lsdb router | display ospf lsdb network | display ospf lsdb ase | YES | | Paloalto | show routing protocol ospf dumplsdb | show routing protocol ospf dumplsdb | show routing protocol ospf dumplsdb | YES | | Ubiquiti[^1] | show ip ospf database router | show ip ospf database network | show ip ospf database external | YES | | Allied Telesis | show ip ospf database router | show ip ospf database network | show ip ospf database external | YES | | Extreme | show ospf lsdb detail lstype router | show ospf lsdb detail lstype network | show ospf lsdb detail lstype as-external | YES | | Ericsson | show ospf database router detail | show ospf database network detail | show ospf database external detail | YES | | Fortinet | get router info ospf database router lsa | get router info ospf database network lsa | get router info ospf database external lsa | YES | | FRRouting | show ip ospf database router | show ip ospf database network | show ip ospf database external | YES |

[^1]:This command applies to the EdgeRouter line and older Unifi USG Gateways. New Unifi Gateway products use the FRRouting Project.

FRRouting (TE): For richer link data (bandwidth, TE metric, admin group), append the output of show ip ospf database opaque-area to the same file. This is optional; the graph still builds from LSA 1/2/5 alone.

LSA 1 and LSA 2 is mandatory and have to exist in the same file. LSA 5 is optional. The output from all commands should be placed in a single file and then be uploaded to Topolograph.

Traffic Engineering (TE) link attributes

Topolograph can use Traffic Engineering (TE) link attributes from your LSDB for better visibility and filtering.

• Parsed values: Link-level TE metric, administrative group (affinity), maximum and reservable bandwidth, and unreserved bandwidth per priority. Useful for capacity planning, path analysis, and finding links that meet or exceed certain TE constraints.
• OSPF: Include show ip ospf database opaque-area in the same upload file as your router/network/external LSDB. Type 10 (opaque-area) LSAs carry the TE data; the rest of the graph is built from LSA 1, 2, and 5 as before.
• IS-IS: TE attributes are taken from the IS-IS LSDB when using supported commands (e.g. FRR show isis database detail). No extra command is required beyond your normal IS-IS capture.
• Using TE in Topolograph: Once a diagram is built with TE data, you can filter edges by TE metric or bandwidth via the diagram edges API (e.g. links with TE metric above a threshold or unreserved bandwidth below a value). The same TE attribute names are used for both OSPF and IS-IS.

Filtering TE links via SDK (topolograph-sdk): Use graph.edges_list() with range operators __gt, __lt, __gte, __lte on TE attributes:

# Edges with TE metric >= 100
edges = graph.edges_list(temetric__gte=100)

# Edges with unreserved bandwidth (priority 0) below 1 Gbps
edges = graph.edges_list(unreserved_bw_0__lt=1e9)

# Edges between two nodes with max link bandwidth above 10 Gbps
edges = graph.edges_list(src_node="1.1.1.1", dst_node="2.2.2.2", max_link_bw__gt=1e10)

TE attributes: temetric, admin_group, max_link_bw, max_rsrv_link_bw, unreserved_bw_0 … unreserved_bw_7.

Supported vendors for OSPFv3 visualization

| Vendor | Command | Stub network included | External (redistributed) network | |---------|---------------------------------------------|---------------------------------------------|--------------------------------------------------| | Arista | show ipv6 ospf database detail | YES | YES |

Supported vendors for ISIS visualization

| Vendor | Command | Stub network included | External (redistributed) network | |---------|---------------------------------------------|---------------------------------------------|--------------------------------------------------| | Cisco | show isis database detail | YES | No, (need tested LSDB for adding it) | | Juniper | show isis database extensive | YES, but need tested LSDB for checking it | No, (need tested LSDB for adding it) | | Nokia | show router isis database detail | YES, but need tested LSDB for checking it | No, (need tested LSDB for adding it) | | Huawei | display isis lsdb verbose | YES, but need tested LSDB for checking it | No, (need tested LSDB for adding it) | | ZTE | show isis database verbose | YES, but need tested LSDB for checking it | No, (need tested LSDB for adding it) |

Visualization via BGP-LS

**BGP Link-State (BGP-L