0 incoming connections

[BlackHatCoiner]

I've removed the vSeeds, changed the pchMessageStart and I'd like to make a connection from my home's node to my VPS'. I ran addnode "<MY_VPS_STATIC_IP>:2333" add and established a connection between these two computers. The problem is that the VPS node doesn't seem to send information to the home node. There's only one outcoming connection from the VPS.

This is what my home node shows:

I guess that's why I haven't received any block while I've mined two on the VPS. Do I have to port forward? Or I can solve this by changing a firewall rule?

[HCP]

So you added the VPS IP address to your home node using addnode? If so, have you also tried using addnode on the VPS to add your home node IP?

[ranochigo]

Connections are bidirectional so its polarity shouldn't play a factor if no information is being transmitted to and from a node. Can you add debug=net into the Bitcoin.conf and see the network messages?

It should provide a picture of the interaction between the nodes and if any messages are being communicated.

[BlackHatCoiner]

So you added the VPS IP address to your home node using addnode? If so, have you also tried using addnode on the VPS to add your home node IP?

Yes I have, but what I'm trying to say is that it doesn't make sense to do that without port forwarding. But even if I did port forward it wouldn't also make any sense either. On the official build of Bitcoin Core (that follows the longest chain), I normally have incoming connections. What difference does it have? Could it be the vSeeds? Isn't addnode enough?

Can you add debug=net into the Bitcoin.conf and see the network messages?

Where exactly should they be? On debug.log? These are the last lines: https://pastebin.com/raw/9TazyZdx

[NeuroticFish]

Or I can solve this by changing a firewall rule?

Imho the VPS has to allow incoming/inbound connections on the correct port (8333?) from your (home) IP.
You should make sure that happens, else you're wasting your time.

[BlackHatCoiner]

Imho the VPS has to allow incoming/inbound connections on the correct port (8333?) from your (home) IP.

Why shouldn't already allow it? How do I check this?

[NeuroticFish]

Imho the VPS has to allow incoming/inbound connections on the correct port (8333?) from your (home) IP.

Why shouldn't already allow it? How do I check this?

I don't know if the specific port is allowed. And I am not an expert, so if you're not in a hurry, just wait for a second opinion.

From what I know, if you try to do Telnet ^{which may need to be installed separately as windows optional feature} on a specific IP and port you can find out if it's anything listening there or not.
For example

Code:

telnet localhost 8333

tells me "Could not open connection to the host, on port 8333: Connect failed", since my bitcoin daemon is not running, but

Code:

telnet localhost 18080

gets me in (no error), since I am syncing my XMR daemon now.

I expect that telnet from VPS "localhost" will work and from your home IP to the VPS won't.

[BlackHatCoiner]

I expect that telnet from VPS "localhost" will work and from your home IP to the VPS won't.

It does work on both, I guess. It doesn't return me that the connection failed and I see this on my "Peers" tab:

The funny part is that I actually receive information from the VPS, I just don't understand why it shows me 0 incoming connections and why I haven't received a block so far:

[ranochigo]

If you're connecting from your computer to that VPS, then it is an outgoing connection and hence the stats would be correct. For you to have an incoming connection, you need to connect from that VPS to the node that you're using. There is no connection that would be both incoming and outgoing as it would serve practically zero purpose.

How many blocks have you created? The thing is that Bitcoin Core expects more than 2 blocks, as seen in the 1.47% from synchronizing block headers. It won't do any IBD without having all of the headers first.

[BlackHatCoiner]

For you to have an incoming connection, you need to connect from that VPS to the node that you're using.

This is the problem. I do run the addnode function with my home's IP from the VPS but it doesn't connect. I'm asking if I should port forward or anything else.

How many blocks have you created? The thing is that Bitcoin Core expects more than 2 blocks, as seen in the 1.47% from synchronizing block headers. It won't do any IBD without having all of the headers first.

I've mined 3 blocks and it should be fined since I modified these lines below from chainparams.cpp:

Code:

m_assumed_blockchain_size = 1;
m_assumed_chain_state_size = 1;

It's supposed to start syncing from block 1. Also, what is "IBD"?

[BlackHatCoiner]

I think I've found out what's the problem, but not a solution to it. I've mined 46 blocks from the VPS and my home node hasn't received anything yet. The headers have reached 100% as you can see:

Once I open the debug.log (from my home node), I see this text below. I notice that it ignores the headers from my VPS node, because it is in initial block download. They're both on the same condition (12 years behind). Is this why they can't share their blocks?

Code:

2021-04-07T10:36:21Z sending sendheaders (0 bytes) peer=0
2021-04-07T10:36:21Z sending sendcmpct (9 bytes) peer=0
2021-04-07T10:36:21Z sending sendcmpct (9 bytes) peer=0
2021-04-07T10:36:21Z sending ping (8 bytes) peer=0
2021-04-07T10:36:21Z initial getheaders (45) to peer=0 (startheight:46)
2021-04-07T10:36:21Z sending getheaders (581 bytes) peer=0
2021-04-07T10:36:21Z sending feefilter (8 bytes) peer=0
2021-04-07T10:36:21Z received: sendheaders (0 bytes) peer=0
2021-04-07T10:36:21Z received: sendcmpct (9 bytes) peer=0
2021-04-07T10:36:21Z received: sendcmpct (9 bytes) peer=0
2021-04-07T10:36:21Z received: ping (8 bytes) peer=0
2021-04-07T10:36:21Z sending pong (8 bytes) peer=0
2021-04-07T10:36:21Z received: addr (31 bytes) peer=0
2021-04-07T10:36:21Z received: getheaders (581 bytes) peer=0
2021-04-07T10:36:21Z Ignoring getheaders from peer=0 because node is in initial block download
2021-04-07T10:36:21Z received: feefilter (8 bytes) peer=0
2021-04-07T10:36:21Z received: feefilter of 0.00001000 PAK/kB from peer=0
2021-04-07T10:36:21Z received: pong (8 bytes) peer=0
2021-04-07T10:36:21Z received: headers (82 bytes) peer=0
2021-04-07T10:36:21Z Synchronizing blockheaders, height: 46 (~93.88%)

[ranochigo]

I can't tell what the problem is unless I take a look at your code. Did you modify the checkpoints as well as the minimum PoW?

[BlackHatCoiner]

I can't tell what the problem is unless I take a look at your code. Did you modify the checkpoints as well as the minimum PoW?

Yes, I modified both of them. I have set

Code:

consensus.nMinimumChainWork = uint256S("0x0000000000000000000000000000000000000000000000000000000100010001");

and

Code:

checkpointData = {
            {
                { 0, uint256S("0x0")}
            }
        };

Here's my chainparams.cpp: https://paste.ofcode.org/CUCKQXEK9f9hb9StQhksAt

[HCP]

Did you create your own genesis block? or are you still using the Bitcoin Core one? If you're still using the 2009 block from Bitcoin Core, then perhaps having effectively 12 years between blocks is not be helping...