Peerinfo example sends/receives repeated messages

[emlautarom1]

Description

When multiple peerinfo examples run concurrently they send to each other more than 1 peerinfo message per interval. Instead, if a peerinfo example conects with a Charon node the peerinfo message is only received once per interval.

How to reproduce

1. Setup a test cluster using Charon

./charon create cluster --nodes 3 --network mainnet --num-validators 1 --cluster-dir ./test-cluster --insecure-keys --fee-recipient-addresses 0x0000000000000000000000000000000000000000 --withdrawal-addresses 0x0000000000000000000000000000000000000000

2. Copy the private keys for nodes 1 and 2 to .node-1 and .node-2 respectively (each directory should contain a single charon-enr-private-key file).

3. Run a Charon node:

./charon run --simnet-beacon-mock --no-verify --nickname=node0 --lock-file=test-cluster/node0/cluster-lock.json --private-key-file=test-cluster/node0/charon-enr-private-key --p2p-tcp-address=0.0.0.0:3610 --monitoring-address=0.0.0.0:9464 --log-level=info

4. Run a Pluto peerinfo example, dialing the Charon node:

cargo run -p charon-peerinfo --example peerinfo -- \
        --port 4001 \
        --nickname node-1 \
        --data-dir .node-1 \
        --metrics-port 9465 \
        --dial /ip4/127.0.0.1/tcp/3610

5. Validate that you're seeing a single PeerInfo log:

2026-01-28T20:32:50.806482Z  INFO peerinfo: Loaded existing private key from .node-1
2026-01-28T20:32:50.809754Z  INFO peerinfo: ENR: enr:-Iu4QCVayGwxN90xAbGqpvvR2TqciZ41ZgRN8mF0675xj2hkQFcnVwl6pWq1gjmUOAZVHBE50oD-HnWX8xlVDQN-hd2AgmlkgnY0gmlwhAAAAACJc2VjcDI1NmsxoQOdy7XC6i8ORmTOkLQNGEl6y4jqJFWlk9uabkp7g88nWYN0Y3CCD6GDdWRwgg-h
2026-01-28T20:32:50.809882Z  INFO vise_exporter::exporter: Created metrics exporter with 23 metrics in 4 groups from crates vise_exporter 0.3.2, charon_tracing 1.7.1, charon_peerinfo 1.7.1, charon_p2p 1.7.1, ...
2026-01-28T20:32:50.813052Z  INFO libp2p_swarm: local_peer_id=16Uiu2HAmPGxXC2xtfqrMo8uLFxeuAczdV1dqFc6cshrqNwHVet8G
2026-01-28T20:32:50.813086Z  INFO peerinfo: Local peer id: 16Uiu2HAmPGxXC2xtfqrMo8uLFxeuAczdV1dqFc6cshrqNwHVet8G
2026-01-28T20:32:50.813100Z  INFO peerinfo: mDNS auto-discovery enabled
2026-01-28T20:32:50.813171Z  INFO peerinfo: Dialing /ip4/127.0.0.1/tcp/3610
2026-01-28T20:32:50.813294Z  INFO peerinfo: Peerinfo example started with nickname 'node-1', interval 5s
2026-01-28T20:32:50.813303Z  INFO peerinfo: Press Ctrl+C to exit
2026-01-28T20:32:50.813526Z  INFO libp2p_mdns::behaviour::iface: creating instance on iface address address=192.168.1.182
2026-01-28T20:32:50.813590Z  INFO libp2p_mdns::behaviour::iface: creating instance on iface address address=100.82.171.62
2026-01-28T20:32:50.813622Z  INFO libp2p_mdns::behaviour::iface: creating instance on iface address address=172.17.0.1
2026-01-28T20:32:50.813764Z  INFO peerinfo: Listening on /ip4/127.0.0.1/tcp/4001
2026-01-28T20:32:50.813797Z  INFO peerinfo: Listening on /ip4/192.168.1.182/tcp/4001
2026-01-28T20:32:50.813815Z  INFO peerinfo: Listening on /ip4/100.82.171.62/tcp/4001
2026-01-28T20:32:50.813841Z  INFO peerinfo: Listening on /ip4/172.17.0.1/tcp/4001
2026-01-28T20:32:50.816948Z  INFO peerinfo: Connection established with 16Uiu2HAmFGE1p3vAxnJ8ghSYuGCiByguyD4SZBu8wu2PcrG1tz7A via /ip4/127.0.0.1/tcp/3610
2026-01-28T20:32:55.818160Z  INFO charon_peerinfo::protocol: Peer name to nickname mappings nicknames={"beautiful-park": "node0"}
2026-01-28T20:32:55.820692Z  WARN charon_peerinfo::protocol: Mismatching peer lock hash peer="beautiful-park" lock_hash="916a191e150f1ab4a358326e7e036290e838997a80e703b500876f6a982c7a51"
2026-01-28T20:32:55.820857Z  INFO peerinfo: Received PeerInfo from 16Uiu2HAmFGE1p3vAxnJ8ghSYuGCiByguyD4SZBu8wu2PcrG1tz7A:
│  Version: v1.7.1-DIRTY
│  Git Hash: 749d2d7
│  Nickname: node0
│  Builder API: false
│  Lock Hash: "916a191e150f1ab4a358326e7e036290e838997a80e703b500876f6a982c7a51"

6. Run a second Pluto peerinfo example:

cargo run -p charon-peerinfo --example peerinfo -- \
        --port 4002 \
        --nickname node-2 \
        --data-dir .node-2 \
        --metrics-port 9466 \
        --dial /ip4/127.0.0.1/tcp/3610

7. Validate that you're seeing multiple Peerinfo messages per node:

2026-01-28T20:33:41.584015Z  INFO libp2p_mdns::behaviour: discovered peer on address peer=16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J address=/ip4/172.17.0.1/tcp/4002/p2p/16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J
2026-01-28T20:33:41.584109Z  INFO libp2p_mdns::behaviour: discovered peer on address peer=16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J address=/ip4/100.82.171.62/tcp/4002/p2p/16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J
2026-01-28T20:33:41.584141Z  INFO libp2p_mdns::behaviour: discovered peer on address peer=16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J address=/ip4/192.168.1.182/tcp/4002/p2p/16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J
2026-01-28T20:33:41.584184Z  INFO peerinfo: 🔍 mDNS discovered peer 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J at /ip4/172.17.0.1/tcp/4002/p2p/16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J
2026-01-28T20:33:41.584306Z  INFO peerinfo: 🔍 mDNS discovered peer 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J at /ip4/100.82.171.62/tcp/4002/p2p/16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J
2026-01-28T20:33:41.584363Z  INFO peerinfo: 🔍 mDNS discovered peer 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J at /ip4/192.168.1.182/tcp/4002/p2p/16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J
2026-01-28T20:33:41.588129Z  INFO peerinfo: Connection established with 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J via /ip4/100.82.171.62/tcp/4002/p2p/16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J
2026-01-28T20:33:41.588287Z  INFO peerinfo: Connection established with 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J via /ip4/192.168.1.182/tcp/4002/p2p/16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J
2026-01-28T20:33:41.588640Z  INFO peerinfo: Connection established with 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J via /ip4/172.17.0.1/tcp/4002/p2p/16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J
2026-01-28T20:33:41.589468Z  INFO peerinfo: Connection established with 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J via /ip4/100.82.171.62/tcp/4002
2026-01-28T20:33:41.589638Z  INFO peerinfo: Connection established with 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J via /ip4/192.168.1.182/tcp/4002
2026-01-28T20:33:41.589791Z  INFO peerinfo: Connection established with 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J via /ip4/192.168.1.182/tcp/54138
2026-01-28T20:33:46.589031Z  INFO charon_peerinfo::protocol: Peer name to nickname mappings nicknames={"helpless-fish": "node-2"}
2026-01-28T20:33:46.589163Z  INFO charon_peerinfo::protocol: Peer name to nickname mappings nicknames={"helpless-fish": "node-2"}
2026-01-28T20:33:46.589245Z  INFO charon_peerinfo::protocol: Peer name to nickname mappings nicknames={"helpless-fish": "node-2"}
2026-01-28T20:33:46.589387Z  INFO peerinfo: Received PeerInfo from 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J:
│  Version: v1.0.0
│  Git Hash: abc1234
│  Nickname: node-2
│  Builder API: false
│  Lock Hash: "00000000"
2026-01-28T20:33:46.589450Z  INFO peerinfo: Received PeerInfo from 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J:
│  Version: v1.0.0
│  Git Hash: abc1234
│  Nickname: node-2
│  Builder API: false
│  Lock Hash: "00000000"
2026-01-28T20:33:46.589507Z  INFO peerinfo: Received PeerInfo from 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J:
│  Version: v1.0.0
│  Git Hash: abc1234
│  Nickname: node-2
│  Builder API: false
│  Lock Hash: "00000000"
2026-01-28T20:33:46.590046Z  INFO charon_peerinfo::protocol: Peer name to nickname mappings nicknames={"helpless-fish": "node-2"}
2026-01-28T20:33:46.590119Z  INFO charon_peerinfo::protocol: Peer name to nickname mappings nicknames={"helpless-fish": "node-2"}
2026-01-28T20:33:46.590136Z  INFO peerinfo: Received PeerInfo from 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J:
│  Version: v1.0.0
│  Git Hash: abc1234
│  Nickname: node-2
│  Builder API: false
│  Lock Hash: "00000000"
2026-01-28T20:33:46.590288Z  INFO peerinfo: Received PeerInfo from 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J:
│  Version: v1.0.0
│  Git Hash: abc1234
│  Nickname: node-2
│  Builder API: false
│  Lock Hash: "00000000"
2026-01-28T20:33:46.590375Z  INFO charon_peerinfo::protocol: Peer name to nickname mappings nicknames={"helpless-fish": "node-2"}
2026-01-28T20:33:46.590463Z  INFO peerinfo: Received PeerInfo from 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J:
│  Version: v1.0.0
│  Git Hash: abc1234
│  Nickname: node-2
│  Builder API: false
│  Lock Hash: "00000000"
2026-01-28T20:33:48.810448Z  WARN charon_peerinfo::protocol: Mismatching peer lock hash peer="beautiful-park" lock_hash="916a191e150f1ab4a358326e7e036290e838997a80e703b500876f6a982c7a51"
2026-01-28T20:33:48.810670Z  INFO peerinfo: Received PeerInfo from 16Uiu2HAmFGE1p3vAxnJ8ghSYuGCiByguyD4SZBu8wu2PcrG1tz7A:
│  Version: v1.7.1-DIRTY
│  Git Hash: 749d2d7
│  Nickname: node0
│  Builder API: false
│  Lock Hash: "916a191e150f1ab4a358326e7e036290e838997a80e703b500876f6a982c7a51"
2026-01-28T20:33:51.590247Z  INFO peerinfo: Received PeerInfo from 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J:
│  Version: v1.0.0
│  Git Hash: abc1234
│  Nickname: node-2
│  Builder API: false
│  Lock Hash: "00000000"
2026-01-28T20:33:51.590353Z  INFO peerinfo: Received PeerInfo from 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J:
│  Version: v1.0.0
│  Git Hash: abc1234
│  Nickname: node-2
│  Builder API: false
│  Lock Hash: "00000000"
2026-01-28T20:33:51.590437Z  INFO peerinfo: Received PeerInfo from 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J:
│  Version: v1.0.0
│  Git Hash: abc1234
│  Nickname: node-2
│  Builder API: false
│  Lock Hash: "00000000"
2026-01-28T20:33:51.590551Z  INFO peerinfo: Received PeerInfo from 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J:
│  Version: v1.0.0
│  Git Hash: abc1234
│  Nickname: node-2
│  Builder API: false
│  Lock Hash: "00000000"
2026-01-28T20:33:51.590801Z  INFO peerinfo: Received PeerInfo from 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J:
│  Version: v1.0.0
│  Git Hash: abc1234
│  Nickname: node-2
│  Builder API: false
│  Lock Hash: "00000000"
2026-01-28T20:33:51.590855Z  INFO peerinfo: Received PeerInfo from 16Uiu2HAmTvWXpcGW3BcGXF4MX7gkSPetYzjXxhUZMUk1FQX5HH1J:
│  Version: v1.0.0
│  Git Hash: abc1234
│  Nickname: node-2
│  Builder API: false
│  Lock Hash: "00000000"

Documentation link(s)

Not applicable

[emlautarom1]

Note that this issue does not happen in MacOS, but it does on Fedora Linux.

[emlautarom1]

The issue seems to be related to mDNS:

• The machine where this was running has 4 network interfaces:

$ hostname -I
192.168.1.182 100.82.171.62 172.17.0.1 fd7a:115c:a1e0::3d01:ab42

• The example peerinfo executable listens on 0.0.0.0, thus all IPv4 interfaces.
• Connections are established for all network interfaces, and peerinfo messages are being exchanged regularly on all of them.

[emlautarom1]

Workaround: Disable mDNS and make the second node dial the first one using a specific interface or loopback (127.0.0.1).

[emlautarom1]

cc. @varex83