Random ports in peer handshake

Question

While looking at the output of getpeerinfo api call, there are random ports on addr and addr local fields. I have set the default network and RPC ports.

I have set the default network ports to be 6001 for both the nodes and connected the daemon by on the same port.

here is an example

[
    {
        "id" : 3,
        "addr" : "11.0.2.19:6001",
        "addrlocal" : "10.0.2.218:40384",
        "services" : "0000000000000001",
        "lastsend" : 1595145954,
        "lastrecv" : 1595145954,
        "bytessent" : 33682716,
        "bytesrecv" : 68302709,
        "conntime" : 1592493648,
        "pingtime" : 0.100124,
        "version" : 70002,
        "subver" : "/MultiChain:0.2.0.10/",
        "handshakelocal" : "1QEXPURG6es3LhbUNux2DELwwJyB1Jqvd9xnV4",
        "handshake" : "14MwcB2MQxLT9bcfUJR5vRrnJdJ8RWAeGGnVV5",
        "inbound" : false,
        "startingheight" : 2734,
        "banscore" : 0,
        "synced_headers" : 8676,
        "synced_blocks" : 8676,
        "inflight" : [
        ],
        "whitelisted" : false
    },
    {
        "id" : 28,
        "addr" : "10.0.4.238:59848",
        "addrlocal" : "10.0.2.218:6001",
        "services" : "0000000000000001",
        "lastsend" : 1595145954,
        "lastrecv" : 1595145953,
        "bytessent" : 6403475,
        "bytesrecv" : 356378,
        "conntime" : 1595140368,
        "pingtime" : 0.05432,
        "version" : 70002,
        "subver" : "/MultiChain:0.2.0.10/",
        "handshakelocal" : "1QEXPURG6es3LhbUNux2DELwwJyB1Jqvd9xnV4",
        "handshake" : "1ZqTLXmJHvWrvpTniZuT4vusFBS1XUqWrZxkLL",
        "inbound" : true,
        "startingheight" : 87,
        "banscore" : 0,
        "synced_headers" : 8675,
        "synced_blocks" : 8675,
        "inflight" : [
        ],
        "whitelisted" : false
    }
]

Is this normal behavior? Will it cause any problems if there are firewall rules in place that only allow communication through the default network port?

 

Thanks

Answer 1

This is normal for all kinds of connections over the Internet. When one node connects to another, it connects to the defined port 6001, but it connects from a random free port number. The firewall and the receiving node don't care about the port being connected from. The communication can still be two-way over a connection made in one direction.

Comments

Thanks got it.