Configuration

CometBFT p2p configuration

This document contains configurable parameters a node operator can use to tune the p2p behaviour.

Parameter	Default	Description
ListenAddress	”tcp://0.0.0.0:26656”	Address to listen for incoming connections (0.0.0.0:0 means any interface, any port)
ExternalAddress	""	Address to advertise to peers for them to dial
Seeds	empty	Comma separated list of seed nodes to connect to (ID@host:port )
Persistent peers	empty	Comma separated list of nodes to keep persistent connections to (ID@host:port )
AddrBook	defaultAddrBookPath	Path do address book
AddrBookStrict	true	Set true for strict address routability rules and false for private or local networks
MaxNumInboundPeers	40	Maximum number of inbound peers
MaxNumOutboundPeers	10	Maximum number of outbound peers to connect to, excluding persistent peers
UnconditionalPeers	empty	These are IDs of the peers which are allowed to be (re)connected as both inbound or outbound regardless of whether the node reached max_num_inbound_peers or max_num_outbound_peers or not.
PersistentPeersMaxDialPeriod	0 * time.Second	Maximum pause when redialing a persistent peer (if zero, exponential backoff is used)
FlushThrottleTimeout	100 * time.Millisecond	Time to wait before flushing messages out on the connection
MaxPacketMsgPayloadSize	1024	Maximum size of a message packet payload, in bytes
SendRate	5120000 (5 mB/s)	Rate at which packets can be sent, in bytes/second
RecvRate	5120000 (5 mB/s)	Rate at which packets can be received, in bytes/second
PexReactor	true	Set true to enable the peer-exchange reactor
SeedMode	false	Seed mode, in which node constantly crawls the network and looks for. Does not work if the peer-exchange reactor is disabled.
PrivatePeerIDs	empty	Comma separated list of peer IDsthat we do not add to the address book or gossip to other peers. They stay private to us.
AllowDuplicateIP	false	Toggle to disable guard against peers connecting from the same ip.
HandshakeTimeout	20 * time.Second	Timeout for handshake completion between peers
DialTimeout	3 * time.Second	Timeout for dialing a peer

These parameters can be set using the $CMTHOME/config/config.toml file. A subset of them can also be changed via command line using the following command line flags:

Parameter	Flag	Example
Listen address	p2p.laddr	”tcp://0.0.0.0:26656”
Seed nodes	p2p.seeds	--p2p.seeds “id100000000000000000000000000000000@1.2.3.4:26656,id200000000000000000000000000000000@2.3.4.5:4444”
Persistent peers	p2p.persistent_peers	--p2p.persistent_peers “id100000000000000000000000000000000@1.2.3.4:26656,id200000000000000000000000000000000@2.3.4.5:26656”
Unconditional peers	p2p.unconditional_peer_ids	--p2p.unconditional_peer_ids “id100000000000000000000000000000000,id200000000000000000000000000000000”
PexReactor	p2p.pex	--p2p.pex
Seed mode	p2p.seed_mode	--p2p.seed_mode
Private peer ids	p2p.private_peer_ids	--p2p.private_peer_ids “id100000000000000000000000000000000,id200000000000000000000000000000000”

Note on persistent peers

If persistent_peers_max_dial_period is set greater than zero, the pause between each dial to each persistent peer will not exceed persistent_peers_max_dial_period during exponential backoff and we keep trying again without giving up.

If seeds and persistent_peers intersect, the user will be warned that seeds may auto-close connections and that the node may not be able to keep the connection persistent.