# Moogsoft Docs

#### Import a Topology

Moogsoft AIOps can use Vertex Entropy and Cookbook calculations to group alerts based on their proximity or topological importance. You can use the topology builder utility to import your network topology into Moogsoft AIOps so it can run these calculations.

To use topology builder, you create a comma-separated value (.csv) file of the node-to-node connections in your network. The utility builds and caches the topology in the moogdb and moog_reference databases. You can also add optional weight to indicate the value of each edge in the network.

##### Before You Begin

Before you import your network topology into Moogsoft AIOps, ensure you have met the following requirements:

• You have generated a map of the connected nodes in your network in a .csv file.

• Your .csv file contains all of the nodes that are expected to send events.

• The lines in your .csv file follow the format: <node1>,<node2>,<weight>. For example:

host_a3,host_a1,3
host_a3,host_a2,3
host_a4,host_a1,3

Topology builder logs and rejects any lines in your file that are not in the correct format. It also ignores any loops such as 'host_x, host_x'. The string node names are case insensitive. The weight values can be decimals.

##### Build a Topology

Build your network topology in Moogsoft AIOps as follows:

1. Import the .csv topology file into the databases using the topology builder found at \$MOOGSOFT_HOME/bin:

./topology_builder -t <file_name>.csv

The -t option defines the topology file. You can use -l to define the level of debug output. For all options see Topology Builder Command Reference.

2. The topology builder utility uses the source data to build a topology. If there is no pre-existing topology, topology builder records host names in the entity_catalog table. By default topology builder assigns each node to the 'Network' group and the 'Unix servers' competency. The utility records the topological information in the moog_reference.one_hop_topo and moog_reference.topo_nodes tables.

After you have imported your topological data, you can use the values in clustering calculations by Cookbook. You can also use the graph analyser utility to calculate the Vertex Entropy of the nodes in your network.

##### Rebuild a Topology

You can rebuild the topology using the -r <percent> option. If you run topology builder and the percentage of new edges in the topology compared to the existing topology exceeds the <percent> value provided, the topology is rebuilt.

For example, if you want to rebuild the topology if at least 50% of the edges are new, run the following:

./topology_builder -t <file_name>.csv -r 50

To force a rebuild of the topology, run:

./topology_builder -t <file_name>.csv -r 0