description: Pantheon networking is about P2P discovery and communication between peers and access to the JSON RPC APIs
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# Networking

Pantheon uses the network to find and connect to peers. 

## Firewalls and Incoming Connections

The default logging configuration does not list node connection and disconnection messages.  

To enable listing of node connection and disconnection messages, specify the 
[`--logging`](../Reference/Pantheon-CLI-Syntax.md#logging) command line option `--logging=DEBUG`.
For more verbosity, specify `--logging=TRACE`.  

The console logs connection and disconnection events when the log level is `DEBUG` or higher.  
If `Successfully accepted connection from ...` is displayed, connections are getting through the firewalls. 

!!! example "Example log output"
    `2018-10-16 12:37:35.479-04:00 | nioEventLoopGroup-3-1 | INFO  | NettyP2PNetwork | Successfully accepted connection from 0xa979fb575495b8d6db44f750317d0f4622bf4c2aa3365d6af7c284339968eef29b69ad0dce72a4d8db5ebb4968de0e3bec910127f134779fbcb0cb6d3331163c`

If connections are not getting through the firewalls, ensure the peer discovery port is open on your firewall. 

## Peer Discovery Port

The [`--p2p-host`](../Reference/Pantheon-CLI-Syntax.md#p2p-host) and [`--p2p-port`](../Reference/Pantheon-CLI-Syntax.md#p2p-port)
options specifies the host and port on which P2P peer discovery listens. The default is `127.0.0.1`
for host and `30303` for port.
 
## Limiting Peers

Limiting peers reduces the bandwidth used by Pantheon. It also reduces the CPU time and disk access 
used to manage and respond to peers.  
 
Use the [`--max-peers`](../Reference/Pantheon-CLI-Syntax.md#max-peers) command line option to reduce 
the maximum number of peers. The default is 25.

## No Discovery

The [`--discovery-enabled`](../Reference/Pantheon-CLI-Syntax.md#discovery-enabled) command line option 
can be used to disable P2P peer discovery.
Set this option to `false` if you are running a test node or a test network with fixed nodes.

Use the [`admin_addPeer`](../Reference/JSON-RPC-API-Methods.md#admin_addpeer) JSON-RPC method to add peers when 
[`--discovery-enabled`](../Reference/Pantheon-CLI-Syntax.md#discovery-enabled) is set to false. 

## Monitoring Peer Connections

Use the [`debug_metrics`](../Reference/JSON-RPC-API-Methods.md#debug_metrics) JSON-RPC API method 
to obtain information about peer connections.