Cardano-node 1.33.0 in P2P mode on mainnet?

I have one of my relays running in P2P mode on mainnet and it seems to be running better than my other relays in normal (“direct connection”) mode.

I added the following to my mainnet-config.json:

  "TestEnableDevelopmentNetworkProtocols": true,
  "EnableP2P": true, 
  "MaxConcurrencyBulkSync": 2,
  "MaxConcurrencyDeadline": 4,
  "TargetNumberOfRootPeers": 100,
  "TargetNumberOfKnownPeers": 100,
  "TargetNumberOfEstablishedPeers": 50,
  "TargetNumberOfActivePeers": 20,

And configured my mainnet-topology.json:

  "LocalRoots": {                                                               
    "groups": [                                                                 
        "localRoots": {                                                         
          "accessPoints": [                                                     
              "address": "relay2",                                 
              "port": 3000                                                      
              "address": "relay3",                                 
              "port": 3000                                                      
              "address": "blockproducer",                                    
              "port": 3000                                                      
          "advertise": false
        "valency": 3
  "PublicRoots": [
      "publicRoots" : {
        "accessPoints": [
            "address": "",
            "port": 3001
        "advertise": false
      "valency": 2
  "useLedgerAfterSlot": 0

The relay has logs like:

TrConnectionManagerCounters (ConnectionManagerCounters {fullDuplexConns = 0, duplexConns = 0, unidirectionalConns = 82, inboundConns = 32, outboundConns = 50})
TrInboundGovernorCounters (InboundGovernorCounters {coldPeersRemote = 0, idlePeersRemote = 1, warmPeersRemote = 0, hotPeersRemote = 31})
TrInboundGovernorCounters (InboundGovernorCounters {coldPeersRemote = 0, idlePeersRemote = 1, warmPeersRemote = 0, hotPeersRemote = 31})
TrConnectionManagerCounters (ConnectionManagerCounters {fullDuplexConns = 0, duplexConns = 0, unidirectionalConns = 82, inboundConns = 32, outboundConns = 50})

I monitor block receipt delay with a script on each relay and it appears that the relay running in P2P mode gets blocks a little quicker than my other relays which each have 20-24 directly configured peers fetched from “”.

Here is a comparison of block receipt delays.

Left side is relay running P2P. Right side is normal mode (relay with 24 directly configured outgoing peers, as well as currently 12 incoming peers)

slot 50158044 delayed 1470ms     slot 50158044 delayed 1510ms
slot 50158061 delayed  750ms     slot 50158061 delayed  780ms
slot 50158063 delayed  560ms     slot 50158063 delayed  550ms
slot 50158079 delayed 1090ms     slot 50158079 delayed 1200ms
slot 50158146 delayed 1750ms     slot 50158146 delayed  860ms
slot 50158151 delayed 1820ms     slot 50158151 delayed 1860ms
slot 50158162 delayed 1060ms     slot 50158162 delayed 1140ms
slot 50158175 delayed 1060ms     slot 50158175 delayed 1120ms
slot 50158192 delayed 1410ms     slot 50158192 delayed 1260ms
slot 50158194 delayed  500ms     slot 50158194 delayed  510ms
slot 50158195 delayed  520ms     slot 50158195 delayed  520ms
slot 50158224 delayed 1540ms     slot 50158224 delayed 1670ms
slot 50158248 delayed  950ms     slot 50158248 delayed 1060ms
slot 50158260 delayed  890ms     slot 50158260 delayed  960ms
slot 50158274 delayed 1080ms     slot 50158274 delayed 1090ms
slot 50158382 delayed 1290ms     slot 50158382 delayed 1530ms
slot 50158393 delayed 1250ms     slot 50158393 delayed 1410ms
slot 50158452 delayed  950ms     slot 50158452 delayed 1110ms
slot 50158459 delayed 1300ms     slot 50158459 delayed 1160ms
slot 50158469 delayed 1170ms     slot 50158469 delayed 1180ms
slot 50158499 delayed  790ms     slot 50158499 delayed 1030ms

In this list of block receipt delays: There are 16 slots where the P2P relay was quicker and only 4 slots where the it was slower.

Is anyone else running 1.33.0 in P2P mode on mainnet?

What experience do others have running P2P on testnet?

Is there something else that should be configured?


Looks complex

p2p on mainnet is unsupported as of today (check release notes), and it would be better not to encourage people to switch it on :slight_smile:

Why? What is the problem?

Isn’t it just a different way of setting up the connections?

Instead of telling my node manually who to connect to by downloading a “suggested” list from a central site like “”, it gets a list from the chain and keeps changing the list depending on quality of connection.

Are you saying something can break? If so what?

This version also adds experimental support for peer-to-peer network. It is unverified and unsupported , and hence not recommended to be enabled in production.

As written in the release notes. A p2p test is currently on going and a different branch is used for that.

Yes. I read that before I started running it.

  • Maybe the node won’t maintain a good list of relays to connect with?
  • Maybe the list I download from will have better connected relays and result in better block receipt times.
  • Maybe in P2P mode the relay will take a longer time to establish enough connections with other nodes so it might get higher block delays for an initial period. However, it does seem like I can overcome this by adding peers in the “PublicRoots” section of the topology.json file.

I get it. There are unknown unknowns. Software can break and fail.

I can deal with the possibility that one of my relays gets disconnected or suffers from a period of poor connectivity.

Having said that, 2 of my IP addresses recently got firewalled from and I was unable to send tip information for a day. I don’t know why, but they got un-blocked a day later. Other IP addresses were not blocked so it seemed like a firewall issue at end. This is the problem with relying on a centralised service.

What if decides to give me a poor list of relays to connect to or even stops providing me a list at all? More importantly, what if doesn’t list my relay addresses in the lists given to other relays? These are known risks.

P2P mode can’t come soon enough!

Currently my P2P mode relay seems to be doing a better job than my other relays.